Laatste bewerking 14.viii.2020
Dichotomous table for gallers on Betula
1a On parts above ground => 2
1b Roots, especially close to stem, with conspicuous, irregular, ± nodule-shaped, massive proliferations. B. pendula, pubescens: Agrobacterium tumefaciens
2a On catkins or fruits => 51
2b On vegetative plant parts => 3
3a On leaves => 18
3b On shoots or buds => 4
4a On shoots => 6
4b Bud galls => 5
5a Buds greatly enlarged; scales loosely adpressed, with outward tips, brownish, grey-silky pubescent. Gall often persistent, sometimes already developing early into small, compact witches’ brooms. Betula spp.: Acalitus calycophthirus
5b Leaf buds swollen, disfigured to a variable extent. B. pendula: Eriophyes leionotus
5c On buds of B. pendula is also reported: Unidentified gall midge
6a On thinner twigs => 12
6b On older stems or branches => 7
7a Bushy malformations in or on the branches => 8
7b Bark of thicker stems or branches with nodule-shaped or open, rim-like margined cancers. Neonectria ditissima
= Globular, several cm large wood balls or the giant wood cancers, observed occasionally have unknown causes and are not true galls.
8a Complete shoot systems are disfigured into conspicuous witches’ brooms, or young twigs with ± pronounced malformations. Usually only the leaves are covered by a short lanuginose grey-white layer of asci => 9
=Regarding compact small witches’ brooms => 5
8b Branches with nodular swellings which give rise to Viscum album
9a Fungi only exceptionally cause witches’ brooms. Northern species => 11
9b Fungi usually cause pronounced witches’ brooms => 10
10a Fungus scattered on many birches. Witches’ broom persistent. Leaves usually lighter coloured than the normal ones, occasionally enlarged but hardly thickened. Betula spp., incl. cultivated foreign species. Taphrina betulina
10b ngus frequently causes pronounced witches’ brooms, but may also develop on many disfigured, ± yellowing leaves without conspicuous malformations of the branches. Taphrina nana
11a Asci with stalk cells. Witches’ brooms only caused exceptionally; the fungus is merely located on darker green areas, on the underside sometimes ± rust-brown discoloured, usually on undisfigured leaves. Taphrina splendens
11b Asci without stalk cells. The fungus is located on often many, sometimes slightly enlarged, soon yellowing leaves of the infected plant, only exceptionally do witches’ brooms disfigure shoots. B. glandulosa, nana, pubescens, x alpestris. Taphrina bacteriosperma
12a Inducer inside the malformations => 14
12b The flat inducers are located in rim-surrounded depressions in the bark and, in case of heavy infestation, sometimes additionally on swollen or disfigured twig => 13
= Minute elevations on twigs of B. pendula, caused by the damselfly Chalcolestes viridis, are not true galls
13a Scale ± pear-shaped, 2.5–3 mm long, white to grey-white, females wine-red. Betula spp.: Chionaspis salicis
13b Scale ± rotund, 1.2–1.6 mm across, whitish to brownish-grey, with dark-yellow median spot. Insect red. Betula spp.: Epidiaspis leperii
14a Shoots with elongated spindle-shaped or ± distinctly separated, nodule-shaped swellings, up to 1 cm wide => 15
14b Young shoots with various proliferations of walls of wounds. Betula spp.: Cryptorhynchus lapathi
= Large nodular outgrowths up to several cm, like those found laterally on young shoots, cannot be attributed to a particular cause and could be considered as teratologies.
15a Inducers inhabit only galls on first-year twigs; galls on woody twigs vacated or occupied by successoria (secondary inhabitants) => 16
15b Older shoots with spindle-shaped thick swelling, up to 50 mm long and 15 mm wide. Gall extending over several internodes, broadest in the upper part caused by a swelling of the woody part; bark only slightly swollen. Inside a long tunnel. B. pendula, pubescens: Unidentified lepidopteran
16a Axis swollen at the top of the shoot => 17
16b Swelling situated below a node, rotund or more or less spindle-shaped, 5–10 mm long; broadest at the node. In a long tunnel inside the pith is a pale-green to greenish-yellow caterpillar with a pale brown head capsule. Exit hole in the leaf axil. Betula spp.: Epinotia tetraquetrana
17a Axis swollen at the top of the shoot. B. pendula, pubescens: Acleris notana
17b Young shoot with a slender swelling on all sides which usually starts below the top and expands downwards over several internodes. Internodes sometimes ± shortened. A tunnel in the pith contains a single caterpillar. B. pendula, pubescens and related species. Heliozela hammoniella
18a Galls on the leaf blades => 23
18b Malformations only on petioles and leaf veins => 19
19a Swellings hardly 2 mm across or smaller => 21
19b Galls several mm long => 20
20a Petiole shortened, over its whole length thickened; at the base of the leaf blade an oblong-elliptical excision. Betula spp.: Heliozela hammoniella
20b Main-, or more rarely lateral veins, occasionally also the petiole, with spindle-shaped, glabrous, hard, pale-green or often also ± purple-red swellings especially visible on the undersides. Each gall contains one single larva; in largely coalesced galls several white, later on pale red larvae. B. pendula, pubescens, x intermedia: Massalongia rubra
20c Much weaker, only up to about 3 mm long, pale green, thin-walled swellings, developing usually solitary per leaf blade on first or second order lateral veins. Containing a single white larva. B. pendula: Unidentified gall midge
21a Each swelling contains a single egg; the emerging larva leaves the rapidly collapsing egg capsule. “Procecidium” (oviposition scars, not true galls ) => 22
21b Up to 2 mm long, corn-like or more wart-like galls, up to 1 mm high, on petioles and veins. Cavity with some short, 1-celled hairs. B. pendula, pubescens: Cecidophyopsis betulae
22a Petiole, more rarely also the midrib, with two rows of egg capsules. B. pendula, pubescens: Hemichroa crocea
22b Egg capsules arranged in one row on the midrib or also on the side veins. B. pendula, pubescens: Craesus septentrionalis
22c In similar way develops on birches Craesus latipes
23a Leaf blade with weak to strong spoon- or bladder-like swellings caused by mites, aphids or fungi, whose asci develop on the galls => 40
23b Malformations different => 24
24a Galls mainly on unfolded leaf blades => 27
24b Leaves folded or rolled upwards => 25
25a Malformations without abnormal pubescence => 26
25b Leaf margin rolled upwards; on older leaves often only at the leaf base; early infected leaf blades may be completely taken up in a leaf roll with densely pubescent surface. Unidentified gall mite
26a The leaf blades of young leaves do not develop completely and remain mostly folded upwards. Midrib and basal part of the side veins thickened, pale green or ± reddened. Several yellowish-white larvae. B. pendula: Resseliella betulicola
= The white larvae of the gall midge Dasineura betuleti live, probably as inquilines, in similar galls which may be caused by the previous specie
26b Leaves close together at the tips of young shoots, severely stunted, rolled, curled and yellow-green. Unidentified thrips
= Stunting of leaves are occasionally caused by the thrips Mycterothrips consociatus
27a Galls situated in the leaf blades => 28
27b Teeth of the leaves with rapidly collapsing egg capsules after the larvae have emerged. “Procecidia” (oviposition scars, not true galls). B. pendula, pubescens: Pristiphora testacea and/or Arge pullata
27cPredominantly on Salix, occasionally on Betula: Pristiphora melanocarpa
28a Leaf blade with ± expanded felt-like cover => 34
28b Leaf galls of roughly defined shape, usually not excessively pubescent => 29
29a Galls wart-, nodule- or ± pouch-like, under 2 mm wide => 31
29b Parenchyma galls; rotund, weakly protruding on both leaf surfaces, about 3–4 mm wide; yellowish, usually red-rimmed. Often several per leaf => 30
30a On B. pendula, pubescens. Each gall contains an initially white, eventually sulfur-yellow larva. Galls usually several per young leaf. Anisostephus betulinus
30b On B. pendula, pubescens. Older leaf blades with solitary or only a few, very flat, concolorous, hardly protruding parenchyma galls. Containing a single pale to lemon-yellow larva. Massalongia betulifolia
30c On B. nana. Similar thick-walled parenchyma galls, strongly arched on the underside. Each gall contains a single orange-reddish larva. Massalongia bachmaieri
31a Galls larger than 1 mm => 32
31b Galls wart-shaped, smaller than 1 mm, golden-yellow translucent, often many on the basal leaves or stems. B. nana, pendula, pubescens: Synchytrium aureum
32a Galls persistent, tough-walled => 33
32b Leaf tips with irregularly distributed egg capsules on the underside which rapidly collapse after the larvae have hatched. “Procecidium” (oviposition scars, not true galls). Betula spp.: Nematus cadderensis
33a Leaf blade with, scattered glabrous nodules, about 1–1.5 mm long, ± reddish, later on browned, protruding strongly on the underside and with an exit hole closed by a rim of rigid hairs; wall of the cavity glabrous. B. pendula, pubescens: Eriophyes leionotus
33b otund, up to 3 mm high, ± pubescent pouch-like protrusions on the leaf upper side, predominantly close to the margin, rarer in the vein axils; wall of the cavity provided with yellowish-white, ± cylindrical, rigid hairs. B. pendula, pubescens: Acalitus longisetosus
34a Hairs cylindrical => 36
34b Hairs club- to toadstool-shaped => 35
35a Erinea dense, ± irregularly margined, initially often intensely red, eventually ± browned, predominantly on upper side, occasionally also on the underside. Hairs irregular head-shaped or ± toadstool-like. Betula spp.: Acalitus longisetosus
35b Dense wine-red coloured erinea with irregular head-shaped hairs; predominantly at the leaf base or along the veins. B. nana: Aceria vinosa
35c Erinea usually on leaf underside, sometimes on both sides, rarely on upper side; initially whitish, later on yellowish, eventually rust-coloured or brownish. Hairs head-shaped, usually longer stalked than those of the previous species. B. humilis, nana, pendula, pubescens, etc.: Acalitus rudis
36a Erinea on the leaf underside, in arched protrusions, predominantly in vein axils => 39
36 Erinea on the leaf underside, also in arched protrusions, but free in the leaf blade or near the margin, or erinea predominantly on petioles or leaf veins => 37
37a Erinea mainly in areas on the leaf blade => 38
37b White, also reddened erinea predominantly on the petioles and on the venation of the leaf base or extending from the stalks into the leaf base venation. B. pendula, pubescens, pubescens var. glabrata, etc.: Eriophyes leionotus
38a Leaf blades of B. nana predominantly close to the margin with ± discoloured archings on the upper side, which contain purple-red to almost whitish felt masses with cylindrical hairs. Aceria fennica
38b Leaves of B. pubescens with upward archings predominantly on the leaf blade, more rarely in the vein axils, which display on the underside ± dense, cylindrical, rigid, whitish-yellow hairs. Acalitus notolius
39a On the upper side arched, glabrous or more rarely weakly pubescent protrusions in the vein axils containing on the underside cylindrical, soon browned, densely packed, not spiralling hairs. B. pendula, pubescens: Acalitus longisetosus
39b Erinea relatively loose, with cylindrical, pointed contorted hairs; usually on the underside in rotund to oval, ± heavily pubescent pale green bladders, situated predominantly in the vein axils at the base of the midrib, more rarely close to the margin or on the leaf blade. B. pubescens & var. pumila, x intermedia: Eriophyes lissonotus
39c In similar galls, but containing beads or short finger-shaped blunt hairs. B. pubescens & var. pumila, x intermedia: Eriophyes leionotus
40a Galls caused by aphids or mites => 44
40b Malformations caused by fungi which fruit on the gall surface => 41
41a Malformations often only locally; on single or several leaves of a shoot => 43
41b Leaves on the infected, systemically attacked shoots often hardly disfigured, although completely or substantially attacked. Leaf blades usually paler, ± slightly enlarged and slightly arched upwards, without conspicuous thickening => 42
42a Fungus frequent or with only boreal-alpine distribution. Initially infections of fungi which occur on the same plant or in the same host population in conspicuous witches’ brooms. Asci with stalk cells
a Leaf blades of young shoots pale green, sometimes slightly enlarged. Axial parts ranging from not disfigured to witches’ broom-like malformations. Betula spp.: Taphrina betulina
b Similar malformations. Betula spp.: Taphrina nana
42b Usually witches’ broom-like malformations develop without simultaneous malformations of shoots and leaves
a Asci with stalk cells. Malformations rarely on axial parts, usually minor on leaves. Betula spp.: Taphrina splendens
b Asci lacking stalk cells. Leaves of the infected shoots often yellowing, sometimes with slightly enlarged leaf blades. Betula spp.: Taphrina bacteriosperma
43a eaves often with conspicuous yellowish or reddish discoloured, thickened, bladder-like swellings. Asci lacking stalk cells. Betula spp.: Taphrina carnea
43b Minor swellings, sometimes several per leaf on early infected young leaves. Infection sites about 2–10 (15) mm across, rotund, ± discoloured. Asci with stalk cells. Betula spp.: Taphrina betulae
43c On leaves, probably non-cecidogenic. Betula spp.: Melampsoridium betulinum
44a Malformations caused by aphids => 45
44b Leaves ± spoon-shaped bent downwards. Leaf blades soon yellowish to brownish discoloured; on the underside with free-living mites. Betula spp.: Epitrimerus subacromius
45a Leaves to various extents folded or curled => 46
45b Leaves with irregular, conspicuous bladder-like swellings, up to 10 mm high, upwardly directed, which occupy a major part of the leaf blade. Aphid egg-shaped, dark purple-red, covered with wax. B. x alpestris, pendula, pubescens: Hamamelistes betulinus
46a Aphids in various shades of yellow or green, or (because of its banded pattern) almost black => 47
46b Aphid dull brown, 2.5–3.5 mm long with brownish transverse stripes; on the underside of irregular undulate leaves. B. pendula, pubescens: Symydobius oblongus
47a Antennae shorter than body => 48
47b Antennae longer than body. Aphid about 2.5 mm long, pale yellowish or –greenish, with yellowish or greenish spots. Younger leaves curled, in cases of heavy infestation upwardly arched. B. pendula, pubescens: Calaphis betulicola and/or Calaphis flava
48a Aphids with dark coloured or margined short siphunculi => 49
48b Aphid about 1.3–2 mm long, greenish-white to pale yellowish-green. Siphunculi very short, yellowish-white, like the also equally short wart-shaped cauda. Antennae reaching beyond the middle of the body. Infected leaves ± distinctly upwardly arched, often withering prematurely; on the underside with considerable colonies. B. humilis, pendula, pubescens: Betulaphis quadrituberculata
49a Aphids more than 2 mm long; siphunculi black or black-green; antennae half the body length => 59
49b phid 1.5–2 mm long, almost egg-shaped, pale or yellowish-green, with broad, dark-green to brown, medially interrupted transverse bands. Antennae often shorter than half the body length. Internodes of young shoots ± stunted. Leaves curled or, in case of heavy infestation, upwardly arched. B. pendula, pubescens: Glyphina betulae
50a Aphid about 2.5 mm long, usually yellowish or greenish, deep to almost black-grey coloured by lighter or darker blackish transverse bands. Siphunculi very short, black; cauda only wart-shaped, green. Leaf margins ± downwardly bent and folded. B. pendula: Callipterinella calliptera
50b Similar malformations. Aphid about 2 mm long, pale yellow, abdomen near thorax with a wide brown-red transverse band, a large greenish-black spot behind, caudal margin brown-red. Siphunculi black-green, cauda pale yellow. B. pendula: Callipterinella tuberculata
51a Malformations visible on outside of catkins => 54
51b Malformations only visible after crumbling the female catkins => 52
52a Gall restricted to fruits, which are enlarged and paler than the healthy ones => 53
52b Galls restricted to the somewhat thickened base of the fruit scales, which are firmly connected to the spindle of the catkin. Containing a single bright orange-red larva. Betula spp.: Semudobia skuhravae
53a Fruit more or less egg-shaped, swollen, dull, more or less pubescent, wings smaller than those of healthy fruits, but distinctly developed. Exit circular, distinct. Contains a single bright orange larva. Betula spp.: Semudobia betulae
53b Fruit almost globular, swollen, glossy, glabrous, wings almost completely reduced, exit indistinctly translucent. Contains a single bright orange-red larva. Betula spp.: Semudobia tarda
= A frequent inquiline is the gall midge Dasineura interbracta, whose pink larvae adhere to the outside of the galls and feed on these galls at the expense of Semudobia betulae as well as S. tarda, larvae of which eventually die
= A less frequent inquiline gall midge: Dasineura fastidiosa, whose pale yellowish larvae adhere to the outside of the galls and feed on these galls at the expense of mainly Semudobia betulae, larvae of which eventually die
54a Caterpillars with distinct thoracic legs => 55
54b Larvae with distinct head capsules, lacking distinct thoracic legs; inside the variously stunted fruit catkins. They tunnel along the spindle of the catkin and feed both on plant tissues and on midge larvae and their galls. B. pendula, pubescens: Betulapion simile
54c Catkin enlarged, caused by gall midges. B. pendula: Unidentified gall midge
= Furthermore the aphid Callipterinella minutissima has been recorded from birch catkins.
55a Catkins shortened, appearing ± thickened, often twisted screw-like and not reaching maturity. B. pendula, pubescens: Cochylis nana
55b atkins similarly stunted. B. pendula, pubescens: Epinotia bilunana
55c Further facultative deformations are occasionally caused by the caterpillar of Epinotia tenerana
Laatste bewerking 23.v.2020
Dichotomous table for gallers on Rhinanthus
1a On parts above ground => 2
1b Roots with nodular swellings. R. minor, serotinus: Meloidogyne hapla
2a On shoot tips, stems or leaves => 4
2b On flowers => 3
3a Flowers transformed into white-woolly, felt-like, succulent masses. Containing many larvae. R. alectorolophus, angustifolius, crista-galli, minor: Rhopalomyia cristaegalli
3b Flowers unopened or half opened. Calyx normal. Corolla poorly developed, reduced, greenish. Stamens and ovaries ± reduced. R. angustifolius: Taeniothrips atratus
4a On stems and leaves => 5
4b Side shoots terminally stunted. Younger leaves clustered, stunted, folded upwards, sometimes ± distorted, transformed into a bud-like to loose tuft-like gall, about 5–8 mm long. Between the mainly basally thickened leaf blades live yellowish-white larvae. R. angustifolius, serotinus: Macrolabis sp.
5a Malformations with erinea, consisting of hairs or conidiophores, on underside of leaves and occasionally also on stems => 8
5b Curling of leaf or swelling of stem => 6
6a Curling of several, usually terminal leaves => 7
6b Shoot axis sponge-like thickened to varied extent, ± curved. More strongly infected plants conspicuously stunted. R. angustifolius: Ditylenchus dipsaci
7a Shoot tip stunted, sometimes curved to one side. Leaves shortened, deflected, locally strongly curled and deep green. R. alectorophus, angustifolius, minor: Philaenus spumarius
7b Tips of vegetative shoots ± stunted. Leaves clustered, slightly curled and deflected. Infected inflorescences with slightly disfigured bracts and ± lacerate flowers. R. alectorolophus, angustifolius: Brachycaudus helichrysi
8a Completely diseased shoots develop faster than healthy ones, internodes thinner and longer, leaves paler, narrowed, appearing arched by deflection of margins. On the leaf underside, usually of the complete leaf blade, a very dense layer of branched conidiophores develops; usually absent from stem parts. R. alectorolophus, alpinus, angustifolius, glacialis, minor, serotinus: Plasmopara densa
8b Underside of the leaves with a greyish purple fungal down, consisting of erect, distally repeatedly dichotomously branched conidiophores. The conidia are elliptic. The host plant does not become disfigured. R. alectorolophus, angustifolius, serotinus: Peronospora pocutica
8c Leaf underside completely or partially with white floccose pubescent pads. Hairs branched or ± club-shaped. Erinea also occurring on stems. R. angustifolius: Unidentified gall mite
Laatste bewerking 23.v.2020
Dichotomous table for gallers on Phlomis
1a On parts above ground => 2
1b Roots with nodular swellings. P. tuberosa: Meloidogyne hapla
2a Leaf blades, stalks or stems with fruiting bodies of rust fungi or leaf blades with erinea => 9
2b Galls caused by insect larvae => 3
3a Galls on vegetative parts => 4
3b Galls caused on inflorescences and flowers. Flower heads contain gall wasp larvae. P. tuberosa: Aulacidea dyakonchukae
= As causer of flower galls, one more gall wasp has been described for P. tuberosa, namely Vetustia investigata
= The gall wasp Panteliella bicolor causes on P. tuberosa outwardly inconspicuously disfigured stems
4a Leaf galls => 6
4b Stem galls caused by cynipid larvae => 5
5a The empty inside of the stem is filled up with monolocular, thin-walled, white, rounded galls, up to 2 mm in diameter. P. tuberosa: Aulacidea phlomica
5b Similar stem gall without externally visible malformation. P. tuberosa: Phanacis phlomidis
6a Leaf galls contain gall midge larvae lacking conspicuous mouth parts => 8
6b Leaf galls contain gall wasp larvae with conspicuous mandibles => 7
7a Leaf blade on upper side with globular, 2–3.5 mm long galls; covered with long, white hairs; on underside conspicuous as small tuft. Containing a single larva. P. tuberosa: Panteliella fedtschenkoi
7b Veins with yellow to brown, spindle-shaped, 1–3 mm long swellings; two larval chambers per gall each containing a single larva. P. tuberosa: Panteliella sp.
8a Subglobular gall, 3–5 mm across, protruding equally on both sides of leaf blade, often close to margin, which is incised; sometimes on petiole, rarely on stem. One-chambered, thin walled. P. cretica, fruticosa, tuberosa: Asphondylia phlomidis
8b Flat irregular pustules on leaves, 3-4 mm in diameter, on the upperside slightly greener than the remaining part of the leaf, on the lower side of the leaf with a slightly hypertrophied epidermis and a partly swollen vein; inside each gall is a chamber where two to four larvae develop together. Usually four to six galls develop on one leaf but up to sixty galls were found on one leaf. In such cases the galls are joined, forming a large irregular pustule with several separated chambers. Larvae pupate in galls, each larva in a white cocoon. P. fruticosa: Phlomidiomyia pustularis
9a Galls with fruiting bodies of fungi on surface => 10
9b Leaf underside with erinea, infestations ± arched. P. tuberosa: Unidentified gall mite
= Similar galls, caused by unidentified gall mites, have been described for P. samia and P. herba-venti subsp. pungens
= The gall mite Aceria onychia causes abnormally hairy disfigured parts on Phlomis fruticosa, tuberosa
10a Up to 10 mm broad, yellow, rotund sori, protruding on underside bearing aecia, on upperside ± depressed pads with spermogonia or ± elongated bulges on main venation, on petioles and young stems. P. tuberosa: Puccinia stipina
10b Aecia on underside, especially on expanded parts or on complete leaf blade; sori occasionally also on petioles and stems, weakly disfiguring the infected organs. Phlomis spp.: Puccinia phlomidis
Laatste bewerking 19.v.2020
Dichotomous table for gallers on Brachypodium
1a On inflorescences or flowerd => 7
1b On vegetative plant parts => 2
2a Leaves with long stripes caused by smuts => 6
2b Malformations caused by animal parasites => 3
2c Whitish, at surface yellowish or brownish patches, which envelope a large area of the upper part of stem, of which further development is stunted. Node of stem rarely swollen, encircled by fungus stroma, yellowish when mature; several nodes may be affected; flowering stunted; stroma contains narrow asci and filamentous spores. Brachypodium spp.: Epichloë sylvatica
3a Localised galls on culms => 5
3b Shoot tip with tuft-like clustering of leaves or complete plant disfigured => 4
4a Especially the tips of subterranean runners with short sheath-like, tuft-like accumulated leaves. Gall up to 40 mm long and 12 mm broad. Larva white with black buccal skeleton. B. pinnatum, sylvaticum: Unidentified chloropid fly
4b Tip of above-ground shoot with spindle-shaped tuft of leaves. Inside a larva causing a severely stunted, broadened culm. B. pinnatum, sylvaticum: Tetramesa brachypodii
5a Stem closely just above a node with 10–12 mm long and 4–5 mm broad, saddle-like depression, thickened at both ends, containing a white larva. Usually ± enclosed by leaf sheaths. B. pinnatum, sylvaticum: Mayetiola hellwigi
5b Culm above one of the lower nodes with an egg-shaped swelling about wheat grain size. Containing a single larva. B. sylvaticum: Tetramesa sp.
6a Often all parts of host diseased, exceedingly leafy; initially developing faster, soon severely stunted, remaining small and sterile. Leaves with long, at first slightly arched patches of smut, then breaking open, ± fraying out the leaves, releasing a black-brown mass of spores. B. pinnatum, retusum, rupestre, sylvaticum: Tilletia olida
6b Similar stripes of smut on the leaf blades of often further developed, hardly additionally leafed plants. Spores rotund to oblong-oval, with many blunt warts. B. pinnatum, sylvaticum: Ustilago striiformis
6c Long conspicuous stripes on chlorotic leaf tissue caused by rust fungus. B. pinnatum, sylvaticum: Puccinia striiformis
7a Spikelets elongated; flowers ± greened, bleached if strongly infected. B. pinnatum: Aceria tenuis
7b lowers leafy; glumes ± enlarged, occasionally enclosed in the spikelet; the midrib bent zig-zag-like. B. pinnatum: ? Ditylenchus sp.
7c Complete plant stunted by scale insects, especially the inflorescence. B. pinnatum, retusum, rupestre, sylvaticum: Eriopeltis festucae
Laatste bewerking 18.v.2020
Dichotomous table for gallers on Aethusa cynapium
1a On stems or leaves => 2
1b Centre of umbel or stalk of umbel ± swollen, club-shaped. Inner wall covered with mycelium. Contains a red larva. Lasioptera carophila
2a Large parts of plant disfigured => 4
2b Stem or leaves with localised galls => 3
3a Stem, and stalks of partial umbels with lateral rounded swellings, 2–3 mm long; with an irregular larval chamber inside. Unidentified beetle
3b Minor, weak bulge-like archings on leaf veins, rachis, -stalk or stem; soon bearing spermogonia and primary uredinia. Puccinia nitida
4a Curled leaf blades caused by aphids or cercopids => 5
4b Younger plants severely stunted. Leaf axis and possibly basal stem parts distinctly shortened, spongy, pale-green, with undulate-wrinkled surface. Ditylenchus dipsaci
5a Larger composite leaves ± nest-like or bell-shaped converged downwards; strongly curled, deep-green close to the froth-covered nymph. On developing plants often several leaves on locally markedly shortened stems are similarly disfigured. Philaenus spumarius
5b Leaves remaining small, rolled, closely accumulated, dark-green discoloured; bearing green aphids. Cavariella aegopodii and/or C. pastinacae
= Also living in summer on several umbellifers is the aphid Hyadaphis foeniculi which might be responsible for the malformations
5c Several leaves stunted and curled; tips deflected. Leaf blades ± knobby swollen, not discoloured. On underside several flat froth-covered nymphs surrounded by a border of white wax hairs. Trioza apicalis
2a Expanded or locally narrowly confined malformations caused by animal inducers => 5
2b Bulge-like swellings on leaf venation, -stalk or young stem parts, caused by fungi => 3
3a Conspicuous, often ± curved swellings, bearing uredinia or telia => 4
3b Bulges of various size on ± curved leaf blades and axis, bearing yellowish spermogonia and aecia. S. carvifolia: Puccinia bistortae
3c Vitreous bulges. S. carvifolia: Protomyces macrosporus
3d Leaves on the underside a white fungal down of erect conidiophores that apically bear a few short branches, each one ending in an ovoid conidium. S. carvifolia: Plasmopara selini
4a Fungus develops only 3-celled teliospores bearing distal spines. S. carvifolia: Nyssopsora echinata
4b Sometimes up to 30 mm long sori coalescing into ± protruding bulges on stems are induced by a mycelium developing primary uredinia and spermogonia. Teliospores 2-celled. S. carvifolia: Puccinia selini-carvifoliae
5a Malformations caused by aphids, spittlebugs or mites => 6
5b Centre of umbel or stalk of umbel ± swollen, club-shaped. Inner wall covered with mycelium. Containing a red larva. S. carvifolia: Lasioptera carophila
6a Malformations caused by aphids or spittlebugs => 7
6b Complete plant variously stunted. Young stems ± distorted. Umbels stunted; flowers ± greened or leafy. S. carvifolia, dubium, silaifolium: Aceria peucedani
7a Leaflets converging, axis ± deflected, leaf blades curled, wrinkled and deep green at site of infestation. S. carvifolia: Philaenus spumarius
7b Stalks of umbel, sometimes in the same umbel, variously shortened. Flowers clustered; the severely stunted organs sometimes variously greened or also leafy. S. carvifolia: Unidentified aphid
Laatste bewerking 17.v.2020
Dichotomous table for gallers on Rhododendron
1a On leaves or flowers => 2
1b Conspicuous, at first whitish, succulent, later on strongly browned, woody proliferations on root collar. Rhododendron spp.: Agrobacterium tumefaciens
2a On shoot tips or leaves => 3
2b The flowers are irregularly ± double. R. ferrugineum, hirsutum, intermedium: Aceria alpestris
3a Malformations of leaf blades => 5
3b Malformations of shoot tips => 4
4a Conspicuous bud-like tuft of leaves on shoot tip. R. ferrugineum: Dasineura rhododendri
4b Terminal buds crippled; often increased in number. Leaves reduced and disfigured. Buds dying prematurely. ‘Shoot tip mite’. R. simsii: Tarsonemus sp.
5a Leaf blade with rolls of margin or pouch-like to spherical galls => 6
5b Leaf blade otherwise weakly disfigured. R. ferrugineum, hirsutum: Cacopsylla rhododendri
6a Roll of leaf margin => 8/p>
6b Succulent galls on leaf blade => 7
7a Leaf blade largely or completely thickened, pale-green, later on densely chalk-white frosted, especially on underside. Sometimes several, almost rosette-like clustered leaves terminally on severely stunted, thickened, young shoots similarly disfigured; galls sometimes also on calyx leaves and even on corolla. “Earlobe disease”. R. caucasicum, indicum, nudiflorum, obtusum: Exobasidium japonicum
7b Up to about cherry-size, succulent, yellowish or often one-sided reddened, later on white frosted, often almost globular galls on leaves, sporadically even on flower parts, as well, sometimes, ± clustered, raceme-like, on shoot tips. R. ferrugineum, hirsutum, x intermedium: Exobasidium rhododendri
7c Galls succulent red-orange. R. luteum, ponticum: Exobasidium horváthianum
8a Leaves on unshortened shoot tip usually narrowly rolled upwards over all their length, lighter; with small 1-celled hairs on both sides. R. ferrugineum, hirsutum, intermedium: Aceria alpestris
8b Leaf margin rolled downwards, ± curled and crippled. R. indicum, molle: Phyllocoptes azaleae
8c Mites living in buds and free on the underside of the leaves. They can cause bronzing and rusting of the young leaves, downwards rolling of the leaf margins and eventually stunting; in nurseries. R. atlanticum, japonicum: Aculus atlantazaleae
8d Rolling of the leaf margin. R. ferrugineum: Aculus thomasi
Laatste bewerking 17.v.2020
Dichotomous table for gallers on Origanum
1a On vegetative parts => 2
1b Corolla unopened, lower part thickened, leather-like, colourless to brown, up to 4 mm long, 2 mm broad; not joined with the slightly swollen calyx. Containing a single larva. O. vulgare: Asphondylia hornigi
2a Malformations of undefined shape on several organs, mainly at tips of shoots => 4
2b Galls on shoot tips, as well as lateral buds or on axial parts of shoots => 3
3a Shoot axis with spindle-shaped or oblong, bulging, multi-chambered swelling. O. vulgare: Thamnurgus kaltenbachii
3b Small, unilateral stem galls, containing a weevil larva or its pupa. O. vulgare: Squamapion origani
3c Shoot tip or lateral buds transformed into oval tufts of leaves, up to 15 mm long and 10 mm broad, greenish, compact. Leaves broadened, thickened, arched, on upperside often with long white hairs. Containing several red larvae. O. compactum, vulgare & subsp. virens: Blastomyia origani
4a Malformations caused by animals => 5
4b Large parts of plant or only single shoots transformed into little, rigid, erect witches’ brooms as result of excessive branching and leafiness. Diseased shoot axis distinctly narrowed; leaves conspicuously reduced. Brownish sori soon develop on axial parts. O. vulgare: Puccinia thymi
4c Leaf blades, especially of young leaves at shoot tip, with thick purple patches bearing spermogonia and aecia, followed by uredinia and telia. O. vulgare & subsp. virens: Puccinia menthae
5a Malformations lacking excessive pubescence => 6
5b Tip of non-flowering or flowering shoots disfigured; developing ± dense masses of felt-like pubescent leaves, and leafy or greened flowers. O. majorana, vulgare: Aceria labiatiflorae
6a Galls caused by aphids => 8
6b Galls caused by gall midges or spittlebugs => 7
7a Roll of leaf margin caused by gall midge larvae. O. vulgare: Unidentified gall midge
7b Shoot axis buckled, bent locally, bearing several deflected, curled, partially deep green leaves. O. vulgare: Philaenus spumarius
8a Several to many leaves at the end of shoots apically increasingly stunted, laterally ± narrowly rolled, curled. Plants often largely disfigured. O. majorana, vulgare & subspp. gracile + virens + viridulum: Aphis origani
8b Leaves curled. O. vulgare: Aphis nepetae
8c Malformations caused by aphids on terminal vegetative- or developing flowering shoots. O. majorana: Myzus ornatus
Laatste bewerking 16.v.2020
Dichotomous table for gallers on Malva
1a On parts above ground => 2
1b Root with nodular swellings. M. sylvestris: Meloidogyne hapla
2a Malformations on vegetative parts, only sometimes encroaching onto primordia of inflorescences => 3
2b Single mericarps between the other hardly changed mericarps conspicuously swollen, up to twice the normal size. Containing a curved beetle larva. M. alcea, multiflora, neglecta, pusilla, subovata, sylvestris, trimestris: Malvapion malvae
3a Expanded malformations of leaves caused by animals => 5
3b Localised galls on stems or small pads bearing sori on all green organs => 4
4a Leaf blades, -stalks, axial parts of shoots, even calyx and green fruits with many small, rotund or oblong, yellowish, eventually red- to dark brown spores bearing bulges. Malva spp.: Puccinia malvacearum
4b Plant ± atrophied; stem thickened, distorted; inner wall browned. M. moschata: Inducer unknown
5a Malformations with abnormal pubescence; caused by mites => 8
5b Malformations lacking abnormal pubescence; caused by aphids, scale insects or spittlebugs => 6
6a Malformations contain aphids => 7
6b Shoot axis often with several oval to spindle-shaped swellings with centrally rimmed depressions which contain a flat froth-covered nymph. M. thuringiaca: Planchonia arabidis
6c eaves curled, deflected, nest-like; often deep green at infestation site. Infestation on erect young plants usually similarly involving several leaves. Containing a froth-covered nymph. Malva spp.: Philaenus spumarius
7a Leaf margin deflected or rolled downwards. Leaf blade variously curled to undulate, sometimes arched, umbrella-like. Infestation often on terminal leaves. Aphids green. Malva spp.: Aphis umbrella
7b Similar, less conspicuous malformations caused by black aphids. M. neglecta, sylvestris: Aphis fabae
7c Leaf blade wrinkled. M. neglecta, sylvestris, thuringiaca: Aphis althaeae
7d Leaf blade ± strongly wrinkled, margins deflected. Containing pale green aphids with siphunculi half as long as to equalling cauda. M. neglecta, parviflora, pusilla, sylvestris, thuringiaca, trimestris: Acyrthosiphon malvae
8a Shoot tip stunted. Leaf blade variously disfigured and atrophied, ± thickened, rolled inwards, curled or undulate and excessively haired; often yellowing prematurely. M. alcea, moschata, thuringiaca: Aceria gymnoprocta
8b Segments of older leaves ± converging and disfigured, bag-like; usually on leaf underside on the thickened veins with dense, yellowish, felt-like pubescence. Younger leaves, densely clustered at shoot tips, similarly but more severely disfigured, often haired on both sides. Erinea also on petioles, shoot axis and calyx. M. alcea, moschata, thuringiaca: Aceria gymnoprocta
Laatste bewerking 15.v.2020
Dichotomous table for gallers on Impatiens
1a On parts above ground => 2
1b Broad spindle-shaped to globular fleshy galls on roots, also variously coalescing. I. balsamina: Meloidogyne hapla
2a On leaves or flowers => 4
2b On stems => 3
3a Mainly basal stem part with considerable, fleshy proliferations. I. balsamina, noli-tangere: Agrobacterium tumefaciens
3b Stem, also petioles, weakly to moderately swollen over a length of 5–100 mm, often variously distorted and densely covered with aecia. I. amphorata, balsamina, capensis, firmula, parviflora, scabrida, sodenii; not on I. noli-tangere: Puccinia komarovii
4a On leaves or cotyledons => 5
4b Flower buds swollen, small and unopened. I. noli-tangere: Unidentified gall midge
4c On flower stalks. I. noli-tangere: Semiaphis noli-tangere
5a On leaves => 6
5b The usually completely diseased cotyledons are paler than the healthy ones, often weakly spoon-like, arched upwards; on underside with whitish-grey down of branched conidiophores. I. balsamina, ?capensis, noli-tangere, walleriana: Plasmopara obducens
6a Leaf blade curled and ± strongly curved => 7
6b Leaf blade with rotund, almost bladder-like swellings. I. noli-tangere: Trioza sp.
7a Malformations caused by aphids => 8
7b Leaf blade deflected, strongly curled, especially close to infestation, often deep green; also clustering, nest-like, of all reduced parts, bulging, ± curved and twisted terminal leaves. Impatiens spp.: Philaenus spumarius
8a Apterae are bright green, pink or red, with extensive shiny brown-black dorsal shield, black siphunculi and yellow to whitish cauda; body length 2.1‒3.1 mm. On undersides of leaves along main veins, and later in dense colonies on flower stalks, of Impatiens spp., especially I. balsamina, balfourii, glandulifera, parviflora: Impatientinum asiaticum
8b Apterae are green with an extensive shiny black dorsal shield, black siphunculi and a pale cauda; body length 2.0‒2.7 mm. Singly or in small colonies on undersides of leaves of Impatiens spp. but especially associated with I. noli-tangere: Impatientinum balsamines
8c Leaf blade ± discoloured, curled and marginally ± deflected by black aphids. I. balsamina, glandulifera, parviflora: Aphis fabae
Laatste bewerking 13.v.2020
Dichotomous table for gallers on Diplotaxis
1a On parts above ground => 3
1b On roots or root collar => 2
2a Roots with conspicuous, mostly, spindle-shaped to cylindrical, fleshy swellings. Inside the galls are cells containing spore masses. D. erucoides: Plasmodiophora brassicae
2b Root collar with one to several rotund galls, up to 5 mm long, with a curved larva inside. D. muralis: Ceutorhynchus assimilis
3a On flowers and siliques => 7
3b On stems or leaves => 4
4a Localised or extensive deformations caused by animal gall causers => 5
4b Leaf blade on the underside with flat, rotund cushions. Leaf axial parts or stem with ± expanded, sometimes distorted bulge-like swellings, initially covered with closed dense white sori, at first-glossy, porcelain-like, with mealy dusting after opening. D. muralis, tenuifolia: Albugo candida
5a Deformations caused by aphids => 6
5b About 10–15 mm long, spindle-shaped, partially deep green swellings on the midribs or stems. Containing a single larva. D. muralis, tenuifolia: Ceutorhynchus chalybaeus
6a oung lateral shoots distinctly stunted; occupied by conspicuously reduced and deformed, more densely situated, leaves. D. tenuifolia: Lipaphis rossi
6b Leaf blades folded locally, leaf margins rolled. D. muralis, tenuifolia: Brevicoryne brassicae
7a Malformations caused by gall midges => 9
8b Other causers => 8
8a Greening of flowers. D. muralis, tenuifolia: Brevicoryne brassicae
8b Ovaries in one or several flowers of an inflorescence deformed, narrowed and elongated; anthers shrivelled, corolla stunted; ± greened; calyx partially conspicuously enlarged. On many parts bulge-like white fungal sori occur. D. erucoides, muralis, tenuifolia, virgata: Albugo candida
9a Malformations of flowers or flower parts => 10
9b Swelling of silique => 11
10a Single or several buds per inflorescence distinctly swollen, unopened. Similar galls; calyx and corolla sometimes less swollen. larva usually lighter yellow, jumping. D. muralis, tenuifolia: Contarinia nasturtii
10b Swollen flower buds. White, non-jumping larvae. D. muralis, D. catholica, D. erucoides: Gephyraulus diplotaxis
10c Swollen siliques, inside only one larva. Pupation in gall. Two generations. D. tenuifolia: Asphondylia stefanii
11a Spindle-shaped swelling of silique, often silique bent at right angle. D. tenuifolia: Dasineura napi
11b Siliques swollen, containing a single orange midge larva. D. tenuifolia:
Asphondylia stefanii
11b Siliques turgid, deformed and curved. D. tenuifolia: Dasineura napi
Laatste bewerking 13.v.2020
Dichotomous table for gallers on Abies
1a On needles, on young, ± stunted shoots or on developing buds => 4
1b On lignified younger or older stem parts => 2
1c arvae develop gregariously (1−8 together) inside young seeds in cones. A. alba, cephalonica, nordmaniana: Resseliella piceae
= Fresh resin masses of damaged shoots of A. alba rarely may contain gall midge larvae of Resseliella crassa and/or R. resinophaga
2a Older lateral shoots, sometimes also the stems, occupied by conspicuous witches’ brooms or mistletoes => 3
2b Axial parts of younger shoots often severely stunted, with ± club-like to nodule-shaped, also forked and twisted swellings, or older stem parts with irregularly expanded, ± bulging proliferations of bark. Sometimes also the buds are transformed into globular or egg-shaped galls. Abies spp.: Dreyfusia piceae
2c A very similar aphid may occur on young plants of A. alba, nordmanniana: Dreyfusia merkeri
3a Witches’ brooms with erect main shoots, abundantly branched, developing from globular to barrel-shaped, often conspicuous thickenings. Needles distinctly shortened, thickened, yellow-green, directed to all sides, falling in autumn. A. alba and several foreign species. Melampsorella caryophyllacearum
= In Melampsorella galls and other cancer-like malformations on conifers the tortricid moth Cydia duplicana, as well as the gelechiid Chionodes electella occasionally develop
3b From bulges, club- and barrel-like swellings of branches or stems arise
Viscum album subsp. abietis
4a On young shoots or on needles => 5
4b Developing buds severely stunted, globular swollen and disfigured, hard and browned. Mites inhabit strobili, apparently causing deformation and atrophy. A. alba, concolor, pectinata: Trisetacus floricolus
5a On many curved needles of ± shortened side shoots => 6
5b Lower third of needles predominantly with brown or red swelling, up to 2 (3) mm long, especially rotund-oval to compact spindle-shaped at base and laterally protruding, expanded over only one or over both needles. Larvae orange-yellow, jumping. A. alba and foreign species: Paradiplosis abietispectinatae
6a Top of shoot slightly shortened. Needles of young shoots weakly swollen, ± tuft-like upwardly converging, exposing wax stripes on the underside; many white woolly aphids between the needles during April-June. Abies spp.: Mindarus abietinus
= Between the needles are pale green aphids of Mindarus obliquus occur in white fluffy wax, resembling those of M. abietinus. Contrary to that species, no malformation of the needles occurs.
6b Needles on the stunted tips of young shoots, predominantly of smaller plants, accumulated, bottle brush-like, partially downwardly deflected. A. alba, nordmanniana etc.: Dreyfusia nordmannianae and/or D. merkeri
6c Another inhabitant on bark of Nordmann fir, also alternating with Picea orientalis: Dreyfusia prelli
Laatste bewerking 12.v.2020
Dichotomous table for gallers on Valerianella
1a On leaves, stems or/and inflorescences => 2
= As causer of root galls on V. locusta has been recorded the Root knot eelworm Meloidogyne hapla
1b Ovary swollen, up to 7 mm long, disfigured. Containing a single white larva. V. carinata, dentata, locusta, rimosa: Cecconia valerianellae
2a Malformations on vegetative organs, sometimes encroaching onto inflorescence primordia => 3
2b Many flowers in an inflorescence conspicuously disfigured. Corolla greatly enlarged, transformed into a lobed, succulent annular disc. Stamens corolla-like. Valerianella sp.: Unidentified gall mite
3a Malformations caused by fungi fruiting on outside => 5
3b Malformations caused by animals => 4
4a Young plants severely stunted. Leaves from basal part upwards variously spongy swollen, the higher situated parts ± disfigured. Stem primordia similarly thickened. V. dentata, locusta: Ditylenchus dipsaci
4b Leaves widened and shortened, ± distorted or rolled. Inflorescence axis shortened. Flowers clustered into rotund, pale green balls. Calyx enlarged, often deeply incised. Tips almost leaf-like, greened or leafy. Stamens aborted. Bracts folded and distorted. V. carinata, coronata, dentata, locusta, rimosa: Trioza centranthi
5a Fungi in expanded, not distinctly restricted malformations => 6
5b Plants usually infected systemically and often not reaching the flowering stage. Organs variously disfigured. Sori on leaf underside, or on all sides of axial parts with ± uniformly arranged whitish aecia. V. carinata, dentata, locusta, rimosa: Puccinia gladioli
6a Plants largely or completely covered by a loose, dusty mycelium. Infected parts variously ± disfigured or often not gall-like V. carinata, dentata, eriocarpa, locusta, rimosa: Golovinomyces orontii
6b On various Erysiphaceae [powdery mildews] develops the widely distributed and rather frequent Ampelomyces quisqualis
6c Systemically infected shoots pale green, on axial parts weakly hypertrophied; leaves slightly thickened, leaf blades ± stunted, margins slightly deflected, with a down of dirty white, branched conidiophores on underside. V. carinata, dentata, discoidea, locusta, rimosa: Peronospora valerianellae
6d Leaves and stem, usually with many, minute greenish to brown globular warts. V. locusta: Synchytrium valerianellae
Laatste bewerking 12.v.2020
Dichotomous table for gallers on Sanguisorba
1a Malformations on leaves, sometimes extending onto the stems => 2
1b Shoot axis or petiole ± buckled or swollen spindle-shaped, sometimes conspicuously curved; often with several flat, oval, rimmed depressions, containing inducer. S. minor: Planchonia arabidis
2a Malformations without conspicuous pubescence => 3
2b Above-ground parts variously disfigured, on most expanded areas with abnormal, dense, whitish, hair felts. Hairs long, twisted. S. minor & subsp. balearica, officinalis, verrucosa: Aceria sanguisorbae
3a Leaf fold, roll or curl caused by animals => 6
3b Small, wart-like or expanded bulging galls caused by fungi => 4
4a Galls bulging, several mm long. Spores develop on gall surface => 5
4b Galls wart-shaped, many-celled, less than 1 mm across, yellow; with many on leaf underside, on leaf midrib, -stalk or young stems; sometimes coalescing into crusts or ridges and causing bends. S. minor, officinalis: Synchytrium aureum
5a Leaf veins, -midrib or stalk, sometimes also young stems, with slightly bulging, sometimes distinctly bent swellings of different length; leaf blades with rotund red-brown pads on upperside, mainly protruding on underside. Galls often brick-red, soon covered with orange spores. Teliospores (2) 4 (5)-celled. S. minor & subsp. balearica, officinalis, rupicola, verrucosa: Phragmidium sanguisorbae
5b Expanded, often ± curved bulges on leaf veins, -spindles, -stalks, also on stems; leaf blade with rotund pads, mainly on underside. Gall soon covered with brick-red spores; telia develop on both sides in arched carbon-black pads, sometimes coalescing with caeoma-sori. Teliospores 4‒22-celled. S. officinalis, verrucosa: Xenodochus carbonarius
5c Malformation of leaf. S. alpina, canadensis, minor & subsp. balearica, officinalis, verrucosa: Podosphaera ferruginea
5c Leaves curled and reddened. S. minor, officinalis: Peronospora sanguisorbae
6a Leaflets curled and ± rolled downwards => 7
6b Halves of leaflet folded upwards, pod-like; especially slightly thickened at veins; outside often ± grey-green, inside ± reddened. Often all leaflets of a leaf are galled. Larvae very many, orange-red. S. officinalis, much rarer on S. minor, officinalis: Dasineura sanguisorbae
7a Malformations caused by spittlebugs or sawfly larvae => 8
7b Leaf blades contracted, curled. S. minor: Unidentified aphid
8a Midrib and leaflet stalks of the still young often pale green leaves slightly thickened and ± stunted, bunched together; axis curled variously up to almost spirally. Leaf blades of leaflet ± folded upwards, often deflected in apical part. S. minor, officinalis: Claremontia puncticeps
8b Especially apical part of leaf midrib distinctly shortened and curved downwards. Leaflets ± bunched together, crumpled, partially dark-green. Froth-covered nymph on underside. S. minor, officinalis: Philaenus spumarius
Laatste bewerking 20.v.2020
Dichotomous table for gallers on Lycopersicon
(= Lycopersicum. ‒ Comp. Solanum)
1a On parts above ground => 4
1b On roots or subterranean stem parts => 2
1c White, velvet cover on all parts of the plant, even underground. Attacked parts turn brown and wither. The conidia (in fact, sporangia) are ovoid or lemon-shaped, with an indistinct apical papilla. They are formed at the tip of seemingly undifferentiated hyphae, that here and there show irregular swellings. Phytophthora infestans
2a Nodular or slender spindle-shaped galls, on roots located distant from surface => 3
2b Buds or adventitious buds of subterranean stem parts, also roots, developing into smaller proliferations, exceptionally up to 20 mm long. Synchytrium endobioticum
3a Nodular swellings, often many and ± coalescing. Meloidogyne hapla etc.
3b Roots usually with shorter or longer, sometimes interrupted, slender, 2–3 mm broad swellings and sometimes excessive development of side roots; this ‘root beard’ is usually situated above the galls. Globodera rostochiensis
3c Tips, often of many roots, slightly swollen over various lengths. Plant often conspicuously stunted. Also many eelworms inside and outside the tissue: Pratylenchus pratensis
3d Root with rounded galls, usually several together like a string of beads; on tomato in glasshouses. Nacobbus cf. aberrans
= Nacobbus serendipiticus (tomato eelworm) is causing spindle-shaped galls on roots in glasshouses
4a On leaves and flowers => 6
4b On stems, sometimes encroaching on leaf midrib => 5
5a Up to 20 (30) mm long, rotund bulge, mainly on root collar, secondarily also on higher stem parts. Agrobacterium tumefaciens
= In cases of the moderately frequent “tomato cancer”, better known as “bacterial tomato withering/drooping” the causer is Corynebacterium michiganense
5b Pale green, spongy, ± expanded swelling, often associated with distortion of ± stunted parts. Ditylenchus dipsaci
6a Various curls or rolls, often of several terminal leaves, caused by aphids => 7
6b Malformations of flowers often with bladder-like swelling, extensively conjoined calyx leaves as well as largely stunting of partially greened corolla leaves and stamens and sometimes enlarged and disfigured ovaries on plants with reduced, often bulging leaves. Stolburg disease
6c Individual flower or part or all of inflorescence greened and leafy (phyllanthy), very haired, containing mites. Aceria lycopersici
7a Aphid dull-black, about 2.5 mm long. L. esculentum: Aphis fabae
7b Aphids pale yellowish to green, 1.8–2.9 mm long, siphunculi pale at base, darker, with a dark spot at tip. Aulacorthum solani
7c Aphid green, often with a dark, green longitudinal stripe on back. Body spindle-shaped oval, glossy in adults, dusted with greyish wax in froth-covered nymphs. 1.7–3.6 mm. Siphunculi brownish, ¼–⅓ of body length, twice as long as cauda. Alates with pale brownish-yellow thorax, otherwise lacking pigmentation on back. Macrosiphum euphorbiae
Laatste bewerking 8.v.2020
Dichotomous table for gallers on Gnaphalium
(incl. Filaginella, Laphangium, Omalotheca, see also Helichrysum)
1a On above-ground parts => 2
1b Roots with 2–3 mm long, spindle-shaped swellings, on which occasionally some lateral roots have developed. G. uliginosum: Meloidogyne hapla
2a Whole plant, or major parts, deformed by aphids or cercopids => 8
2b Galls on shoots => 3
3a Spindle-shaped or globular galls of almost constant shape, but of various size => 5
3b Malformations of various shape and nature => 4
4a Galls on young, often severely stunted, plants. Basal parts, especially stems, also including the leaf bases, spongy, swollen, with many eelworms inside. G. uliginosum: Ditylenchus dipsaci
4b Sometimes strong swelling of the stem on the tip of ± developed shoots or the inflorescence. Leaves clustered, with swollen base, abnormally pubescent. G. sylvaticum: Cause unknown – ? gall mite
5a Galls spindle-shaped, with larvae inside => 6
5b Rotund, up to 5 (10) mm long galls; the inside containing whitish-yellow, later on rust brown, spore masses; predominantly on root collar, occasionally concentrated in groups. More rarely small galls on higher stem parts, even in the inflorescence. Laphangium luteo-album, G. sylvaticum, G. uliginosum: Entyloma magnusii
6a Inside the galls are larvae with head capsules => 7
6b Spindle-shaped swellings, up to 6 mm long and 4 (5) mm thick, usually in upper stem parts, the inside with a sometimes laterally situated whitish larva without distinct head capsule. G. sylvaticum, uliginosum: Actinoptera discoidea
7a Hard ovoid, one-chambered swelling in flower head or stalk. One larva. G. sylvaticum: Acentrotypus brunnipes
7b Spindle-shaped swelling on terminal part of shoot. With a yellowish-white, transversely lightly pink striate caterpillar with pale to dark brown head inside. Laphangium luteo-album: Eucosma albidulana
8a Caused by aphids => 9
8b Shoot stem usually stunted on one side, leaves clustered, the leaf blades curved downward, ± curled and dark green close to the froth-covered nymph. G. sylvaticum: Philaenus spumarius
9 Central part of rosettes deformed; or top of vegetative shoots, also the inflorescence, with shortened and sometimes twisted stem; leaves, sometimes capitula, clustered, rolled, curved. Aphids white frosted by copious secretion of wax. Filago arvensis, germanica, lutescens; Gnaphalium sylvaticum, uliginosum: Pemphigus populinigrae
9b Top of shoot stem stunted, leaves clustered, curved. Aphid bright yellow to yellowish-green, 1.5–2 mm long, without secretion of wax. G. sylvaticum, G. uliginosum: Brachycaudus helichrysi
Laatste bewerking 5.v.2020
Dichotomous table for gallers on Arabidopsis
1a On parts above ground => 2
1b Main- and side roots with conspicuous, spindle- to barrel- shaped succulent swellings. Inside with many cell masses with minute spores. A. arenosa, lyrata subsp. petraea, suecica, thaliana: Plasmodiophora brassicae
2a Malformations caused by fungi, with fructifications developing at surface => 6
2b Malformations caused by animals => 3
3a Malformations of flowers or siliques => 8
3b Spindle-shaped or expanded swellings on stems or petioles => 4
3c Large parts or complete plant disfigured. Shoot severely stunted; flower parts severely disfigured, often greened or reddened. Aphid more frequent on Arabis: A. lyrata subsp. petraea, thaliana: Lipaphis rossi
3d Leaf blade stunted, rolled upwards, curved; covered with abnormal pubescence. A. arenosa: Aceria drabae
4a Swellings ± spindle-shaped and glabrous => 5
4b Shoot severely stunted, like the basal parts of lower leaves variously swollen, spongy, pale green. A. thaliana: Ditylenchus dipsaci
5a tem with about 5–7 mm long, 2 mm thick, spindle-shaped swelling. The pith contains a single larva. A. arenosa, suecica, thaliana: Ceutorhynchus atomus and/or C. griseus
5b Rotund, fleshy swelling of the root collar, up to 10 mm; the single gall chamber containing a single legless, curved larva. A. arenosa: Ceutorhynchus assimilis
5c Spindle-shaped gall, 10‒20 mm long, in the leaf stalk (less often in the stem or a thick vein). A. arenosa: Ceutorhynchus chalybaeus
5d Shoot axis or petiole with spindle-shaped, often strongly arched thickening. Side branches of inflorescence ± shortened. A. thaliana: Inducer unidentified – ? lepidopteran
6a Malformations caused by fungi with white fruiting bodies => 7
6b Diseased shoots ± etiolated; internodes ± elongated and narrowed. Leaves often smaller, pale green; leaf blades slightly thickened, on underside over large areas with dense, ± rust brown sori. A. arenosa, halleri, petraea, thaliana: Puccinia thlaspeos
7a Sori densely clustered, bulging, at first closed, glossy, porcelain-like, then rupturing and with mealy dusting; oblong-oval on stems and inflorescence stalks, often arching the stems. On leaf underside rotund, often without malformations. Conidia developing in chains. A. arenosa, halleri, suecica, thaliana: Albugo candida
7b Sori expanded, with loose cover of branched conidiophores. Infected stems pale green, slightly thickened and arched, especially in flowering part; flowers severely stunted. A. thaliana: Hyaloperonospora arabidopsidis
7c Leaves somewhat disfigured with pale spots on the upperside, that correspond with a fungal bloom on the underside, consisting of erect, apically strongly branched conidiophores. A. arenosa, ? halleri, ? petraea: Hyaloperonospora cardaminopsidis
8a Flowers swollen, unopened; containing several pale yellow, jumping larvae. A. arenosa, cebennensis: Contarinia nasturtii
8b Flowers disfigured, ± leafy; abnormally pubescent. A. arenosa: Aceria drabae
8c Siliques slightly disfigured, hardly inflated. Young seed soon filled with yellowish to grey-violet masses of spores. A. petraea: Thecaphora thlaspeos
Laatste bewerking 10.xi.2020
Dichotomous table for gallers on Coronilla
1a On parts above ground => 3
1b Galls on roots => 2
2a Main- and side roots often with many fleshy nodules, up to about 7 mm long and 4 mm broad, oblong-oval, or at proximal part flattened and ± subdivided, laterally inserted. Coronilla spp.; Securigera spp.: Rhizobium leguminosarum
20b Irregular rotund, little galls on main root with central larval chamber. Each gall contains a single beetle larva. C. scorpioides: Catapion pubescens
3a On stems, buds or fruits => 6
3b On leaves => 4
4a Leaf blade folded or rolled inwards, caused by animals => 5
4b Internodes of completely diseased young shoots elongated; petioles and midrib ± thickened; leaf blades reduced, thickened, soon covered with grey-violet down of branched conidiophores on underside, Coronilla coronata, repanda subsp. dura, scorpioides; Securigera varia: Peronospora coronillae
5a Leaflets folded pod-like on midrib, the middle part especially strongly thickened. Securigera varia: Unidentified gall midge
5b Pale, indistinct pod-like folds of leaf blades of Securigera varia: Unidentified thrips
5c Leaflets twisted, folded, rolled inwards at margin. Coronilla coronata, Securigera varia: Aculus coronillae
5d Malformation of leaves and/ or inflorescences, flowers. Coronilla valentina subsp. glauca + pentaphylla: Hemitrichapion andalusiacum
6a Midge galls in axillary buds or in pods => 7
6b Basal stem parts with ± expanded, often curved, bulging swellings, with single- or several rimmed depressions. Coronilla spp.; Securigera spp.: Planchonia arabidis
7a Pods disfigured => 10
7b Malformation of vegetative tissues => 8
8a Gall cavity absent, or if present, not covered with mycelium => 9
8b Gall cavity lined with mycelium. Leaf axil with bud-like gall, mainly arising from the fleshy thickened lower part of petiole and enlarged stipules. Inner wall with mycelium. Containing a single larva. Coronilla minima: Asphondylia coronillae
9a Irregular clusters consisting of hypertrophied leaflets, terminally on stem, rotund or egg-shaped, of variable size (averaging 8–9 x 7–8 mm), succulent, green- or pink-coloured. Containing several red, dull midge larvae. Coronilla juncea, valentina subsp. glauca: Dasineura coronillae
9b Leaflets pod-like swollen. Larvae glossy and jumping. Securigera varia: Contarinia coronillae
10a Pod with rotund to egg-shaped swelling. Inner wall with mycelium. Containing a single larva. Coronilla coronata, minima; Securigera varia: Asphondylia baudysi
10b Locally ± globularly swollen pods. Coronilla minima: Asphondylia coronillae
Laatste bewerking 3.v.2020
Dichotomous table for gallers on Serratula
1a Galls on stems and leaves => 2
1b Receptacle hardened, partially deformed into a bulging, tough-walled, short, conical to egg-shaped gall. One larva per chamber. S. tinctoria: Trupanea stellata and/or Urophora spoliata
1c Galls located at the base of the flower head, unilocular, ovate, thin-walled, up to 1.5 mm in length; usually the flower head is not malformed and enlarged, galls inconspicuous externally Klasea radiata, Serratula coronata: Aulacidea serratulae
1d Galls in flower heads. Klasea erucifolia, lycopifolia, nudicaulis, radiata:
Isocolus serratulae
1e Galls in flower heads, without symptoms of external deformation. Serratula spp.: Phanacis eugeniae
2a Galls in the shoot tips => 7
2b Leaves with localised or expanded malformations, which may extend into the stems => 3
3a Wart-shaped rotund or spindle-shaped swellings caused by fungi => 5
3b Expanded, glabrous or pubescent malformations caused by animal inducers => 4
4a Leaves curved at the tip, leaf blade curled, the margin ± curved downwards. Sometimes on several similarly malformed leaves terminally clustered on ± shortened internodes. S. tinctoria: Philaenus spumarius
4b More or less conspicuously stunted leaves with curved, curled or bulge-like swollen leaf blades; leaf tips often rolled. Rolls either glabrous or, like the leaf blades, with spotted, striped white or reddish erinea. S. tinctoria: Aculus rigidus
4c Conspicuous spindle-shaped galls, about 8 x 3 mm long, on petioles, also on midribs, to a lesser extent on lateral veins of the leaf blade of S. tinctorial: Loewiola serratulae
4d Lignified but relatively soft stem deformation, differently shaped, which depends on the number of larval chambers. Klasea erucifolia: Aulacidea ascanica
5a Malformations with fruiting fungal sori on the surface => 6
5b Galls hardly 1 mm long, multicellular, wart-shaped, ± golden yellow translucent; many on the underside of basal leaves. S. tinctoria: Synchytrium aureum
6a Leaf blade with rotund spindle-shaped swellings, up to 8 mm long, on the venation, usually conspicuous yellow or red margined, on the underside sometimes weakly arched, with cylindrical cup-shaped aecia occupied sori. S. coronate, tinctoria: Puccinia schroeteriana
6b Slightly bulging swellings on the midribs, less often on the lateral veins; occupied by bright brown uredinia. S. coronata, tinctorial: Puccinia hieracii
6c In SE-, C-Eu; with similar biology on Klasea bulgarica, lycopifolia, radiata; Serratula coronata, tinctoria: Puccinia schirajewski
7a Galls at the shoot tips => 8
7b Shoot terminally with spindle-shaped swelling. In the pith is a single caterpillar. S. tinctoria: Eucosma albidulana
8a Leaves on the shoot tip transformed into an erect, up to 15 mm long, cone-shaped pale gall. Several red larvae. S. tinctoria: Unidentified gall midge
8b More or less rosette- or sometimes almost bud-shaped clustering of leaves on stunted shoot tips. Infected organs often with conspicuously white or reddish pubescence. S. tinctoria: Aculus rigidus
Laatste bewerking 3.v.2020
Dichotomous table for gallers on Melilotus
1a On above ground parts => 3
1b On roots => 2
2a Nodular or spindle-shaped swellings. M. officinalis: Meloidogyne hapla
2b Globular or up to 8 mm long, cylindrical, forked or coral-like branched nodules. Melilotus spp.: Sinorhizobium meliloti
3a On inflorescences, flowers or fruits => 9
3b On vegetative organs => 4
4a On shoot axis or leaves of fully developed plants => 5
4b Young plants considerably stunted. Stems shortened, spongy, thickened. Leaves clustered, occasionally the axial parts swollen, leaf blades distorted. Melilotus spp.: Ditylenchus dipsaci
5a On shoot axis => 7
5b On leaves => 6
6a Leaflets folded upwards, halves at base ± adnate and swollen, together with midrib, into a globular or oblong gall, up to 6 mm long, protruding on underside. Containing a yellowish beetle larva. M. albus, altissimus, dentatus, officinalis: Tychius crassirostris
6b Weaker swelling of midrib of leaflet. Containing a single larva. M. albus, altissimus, officinalis: Tychius meliloti
7a Inducer inside the gall => 8
7b Acuminate-rotund- to oblong oval, often snapped off, or ± bent, expanded bulging swellings of stem, containing in rimmed depressions the inducer. M. dentatus, officinalis: Planchonia arabidis
8a Rotund to spindle-shaped swelling, 5–15 mm long. The pith containing a maggot. M. albus, dentatus, officinalis: Melanagromyza submetallescens
8b Weak swelling, inside a compact pith containing several white larvae. M. albus: Unidentified dipteran
9a All flowers of a plant occasionally disfigured and ± pubescent. Calyx hardly disfigured, corolla and anthers often reduced, ovary developing into a short, leafy cone, transformed together with the axils of stipules, developing shoots into a ± dense leafy inflorescence. M. albus, altissimus, dentatus, officinalis: Unidentified gall mite
9b Flower buds swollen, unopened. M. altissimus, officinalis: Contarinia sp.
9c Flowers strongly greened; beetle larva living inside stem just below inflorescence. M. albus, altissimus, dentatus, officinalis: Stenopterapion meliloti
9d Beetle larvae feed within the pod on the developing seed; this may cause some galling of the pods. M. albus, ? altissimus, officinalis: Tychius breviusculus
Laatste bewerking 2.v.2020
Dichotomous table for gallers on Lythrum
2a Malformations on various vegetative as well as generative parts => 5
2b Globular to spindle-shaped galls on shoot axis => 3
3a Galls caused by weevils. In the gall a legless, curved weevil larva => 4
3b Weak, oblong swellings close to shoot tip. L. salicaria: Unidentified gall midge
4a Long spindle-shaped or rotund swelling, usually one-sided, succulent, one- or more-chambered on lower parts of shoot axis. Apically organs sometimes severely stunted. L. hyssopifolia, ? salicaria: Nanomimus hemisphaericus
4b In similar one- or more-chambered galls. L. hyssopifolia, salicaria: Nanomimus circumscriptus
4c Side shoots with a swelling, up to 8 mm long, rotund-oval, one-chambered. Containing a single larva. L. portula: Dieckmanniellus gracilis
4d Slender spindle-shaped stem galls, 12–18 mm long, usually at leaf insertions of several L. hyssopifolia, junceum, salicaria: Dieckmanniellus nitidulus and/or D. helveticus
4e Small conspicuous swelling of stem, laterally protruding, variously expanded. L. acutangulum, hyssopifolia, salicaria: Nanophyes globiformis
4f Inconspicuous swelling of the stem. L. salicaria: Nanophyes rubricus
5a Malformations mainly involve unfolded leaves => 6
5b Lateral buds or tips of vegetative shoots disfigured. All leaves of infected axillary buds severely stunted, adnate at base, developing into a gall up to 6 mm long, ± reddened with free terminating apex over differing length. Infestation of shoot tip results in stunting of axial parts with tuft-like clustering of basally largely stunted leaves. Infected flower buds swollen at base; calyx hardened. Stunting of all other parts; usually unopened. Depending on gall size a single or several orange-yellow larvae. L. salicaria: Bayeriola salicariae
6a Malformations caused by aphids or spittlebugs => 7
6b Petioles swollen over a length of about 10 (15) mm, slender pear-shaped. Galls succulent, one-chambered. Leaf blades severely stunted. Containing a single larva. L. hyssopifolia, salicaria: Nanomimus circumscriptus
6c Minor swellings of leaf. L. portula: Chlorochytrium rubrum
7a Malformations caused by aphids => 8
7b Leaf blade deflected, curled, locally deep green; infestation close to shoot tip results in one-sided stunting and distortion of axial parts, associated with clustering of similarly disfigured leaves. L. salicaria: Philaenus spumarius
8a Clustering of disfigured leaves or also failed flowers on ± stunted shoot tips caused by aphids, about 2 mm long, pale to yellowish-green. L. hyssopifolia, salicaria, virgatum: Myzus lythri
b8 Clustering of ± stunted, deflected and curled leaves on less stunted shoot tips or similar malformations on several lower situated leaves caused by black aphids. L. salicaria: Aphis fabae
Laatste bewerking 2.v.2020
Dichotomous table for gallers on Teucrium
1a Flower galls => 17
1b On stems, shoot tips, buds or leaves => 2
= Root galls of Meloidogyne hapla are known from Teucrium
2a Localised or expanded galls restricted to the leaf blades of single or several leaves => 13
2b On shoot tips, terminal leaves, buds or stems => 3
3a On buds or on tips, terminally on shoots => 8
3b On stems, partially encroaching into lateral leaves and buds => 4
4a The causers live, and/or fruit inside the galls => 7
4b The animal causers live on the outside of the galls or fungi develop their fruiting bodies on the outside => 5
5a Malformations expanded, slender and elongate, of irregular shape, large parts covered with dark-brown telia at maturity => 6
5b Mainly basal part of stem with spindle-shaped to irregularly bulging, often distorted swellings which contain in a single or several rimmed depressions single froth-covered nymphs. Teucrium spp.: Planchonia arabidis
6a The ± dusty, black-brown sori develop on stems, sometimes also on petioles, as well as on leaf undersides, ± disfiguring the organs. T. montanum, orientale: Puccinia constricta
6b Sori similar, black. Gall-like malformations facultative, rare, of variable shape. Diseased shoots sometimes with extensive sori, occasionally distorted and curved, sometimes almost witches’ broom-like disfigurations, usually sterile. Teucrium spp.: Puccinia polii
7a Irregular, compact swellings or proliferations on root collar or stem base on one side or enveloping the stem. Black spore masses develop inside the galls. T. montanum: Melanotaenium jaapii
7b Only a few swellings, ± irregular spindle-shaped or nodule-like, up to 10 mm long. Shoot necrotic above gall. Containing single to many larvae. T. fruticans, scorodonia: Thamnurgus kaltenbachii
8a On shoot tips or lateral buds => 12
8b On several leaves terminally, usually on only slightly stunted shoots => 9
9a Malformations caused by gall mites => 11
9b Malformations caused by aphids or spittlebugs => 10
10a Leaves on shortened shoot tips clustered into loose, almost cone-like galls. Teucrium spp.: Aphis teucrii
10b Stem terminally ± distorted and curved over ± 3 internodes, leaves inserted nest-like, converging, curled, locally dark-green. T. scordium, scorodonia: Philaenus spumarius
11a Plants usually excessively branched. Leaves disfigured. T. montanum: Unidentified gall mite
11b Leaves and stem on sometimes shortened tip of vegetative shoots with densely felt-like pubescence. T. scorodonia: Unidentified gall mite
12a Buds on main- and side shoots compact. Outside leaves almost normal, arranged artichoke-like, the inside ones bear single to several orange-red larvae. T. capitatum & subsp. lusitanicum, chamaedrys, salviastrum, scorodonia: Dasineura teucrii
12b Leaves clustered terminally on ± stunted shoots, thickened, disfigured, forming densely pubescent tufts. T. scorodonia: Unidentified gall midge
13a Leaves often with yellowish bulges in the leaf blades, rotund, protruding on underside; on venation or stalks ± spindle-shaped to oblong-oval, soon covered with sori densely covered with brownish telia => 16
13b Malformations without externally protruding sori of fungus => 14
14a Galls a few mm across, pustule- or wart- shaped or ± oblong-oval => 15
14b Leaf blade twisted and curled. Containing many larvae. T. chamaedrys: Unidentified gall midge
15a Leaf blades, especially of the middle and upper stem leaves, with many uneven bulges, protruding at upperside, often situated along the margins; pale yellow on upperside, sometimes ± strongly pubescent; open on underside, inside with emergentia or strong abnormal pubescence T. capitatum subsp. gracillimum, chamaedrys, murcicum, scordium: Aculus teucrii
15b Leaf blades of basal leaves with many swellings, mainly protruding on underside, 1–3 mm long, at first yellowish-green, later on almost black-brown, ± pock-like. Sometimes joined into dense groups on the ± curved veins or stalks; more rarely in the bark of lower stem parts. T. scorodonia: Physoderma vagans
16a Sori with grey-brown spores, often many; arched on the underside of leaves; on upperside often ± depressed; occasionally causing distortions of axial parts of younger leaves. More rarely but then similarly on stems. T. botrys, chamaedrys, pyrenacium: Puccinia chamaedryos
16b Similar pads or bulges, causing conspicuous distortions on axial parts. Teucrium spp.: Puccinia annularis
17a Malformations of flowers caused by gall midge larvae => 19
17b Galls caused by lacebugs => 18
18a Corolla weakly thickened, especially upper part slightly enlarged, unopened, stamens and sometimes pistil weakly swollen. T. canum, chamaedrys, polium, scorodonia: Copium clavicorne
18b Flower swollen up to two or three times the normal size. Corolla strongly swollen, especially at base. Calyx disfigured, lacerated, ± thickened, yellowish. Stamens and pistil ± stunted. Gland hairs abnormally enlarged. T. capitatum & subsp. gracillimum, gnaphalodes, montanum, polium: Copium teucrii
19a Galls on T. scordium or scorodonia => 20
19b On T. montanum. Flower disfigured. Corolla inflated, bladder-like. Unidentified gall midge
20a On T. scordium. Flower swollen, unopened. Containing a single larva.
Unidentified gall midge
2b On T. scorodonia. Flowers clustered, enlarged, unopened. Ovary almost capsule-like, stalked, enlarged, pubescent. Pistil shortened. Unidentified gall midge
Laatste bewerking 2.v.2020
Dichotomous table for gallers on Larix
1a On tips of main and side shoots, on male flower buds or on needles => 5
1b On stem parts, branches or twigs => 2
1c Orange-red larvae develop in cones of L. decidua, x polonica: Resseliella skuhravyorum
2a On older stem parts or on thicker branches => 4
2b On thinner twigs => 3
3a Oblong or often nodule-shaped, cherry- to hazelnut-size swelling on younger stems or twigs, often at the base of a branching and ± covered with a grey resin blister. L. decidua: Cydia zebeana
3b Elongate resinous swelling about twice stem width at its widest; soft and spongy, becoming hard and woody after adult emerges in May, June. Containing caterpillar for 22 months from June onwards, pupa April, May second year. L. decidua: Cydia millenniana
3c Bark of twigs with small swellings, pubescent inside. L. decidua: Trisetacus laricis
4a Long club-shaped swelling on stems and branches, bearing a bush of mistletoe. L. kaempferi: Viscum album
4b Scurfy, cracked, ± dark coloured, 15–40 cm long patches of bark ± deeply depressed, rimmed at margin with resin reacting with cancers on at first sometimes swollen parts of branches, occasionally also on the stems. Infections starting from 2–4 year old branches. L. decidua: Lachnellula willkommii
5a On the tips or short- and long shoots, also on male flower bud => 7
5b Needles slightly thickened, discoloured, almost bent over at right angles; an aphid present at the bending point => 6
6a Aphid dark brown to black, naked or covered with wax flakes. L. decidua, x eurolepis, gmelinii, kaempferi, laricina, lyallii, sibirica: Adelges laricis
6b Aphid yellow-green to dark green, without wax cover, only slightly frosted. L. decidua, x eurolepis, kaempferi, sibirica: Sacchiphantes viridis
6c To the same species group belongs the anholocyclic (only asexual females known), only on Larix spp. living: Sacchiphantes segregis
7a Tips of previous year’s short shoots swollen ± hemispherically. Galls up to pea-size, also the male flower buds occasionally transformed to similar, more or less egg-shaped, usually larger galls. Galls to August with brown scales, covered later on at first with bright fluid, then white crumbly resin, driving neighbouring needles widely apart, star-like. Containing a single brick-red larva in the upper part of the gall. L. decidua, occidentalis: Dasineura kellneri
7b Similar, globular to oblong-egg-shaped brown galls; often also on terminal buds of long shoots; in contrast with the previous midge galls, which may also be present, always dry, lacking a resin cover. L. decidua: Trisetacus laricis
Laatste bewerking 1.v.2020
Dichotomous table for gallers on Thalictrum
1a On plant parts above ground => 2
1b Roots with slender spindle-shaped swellings, up to 5 mm long. T. aquilegiifolium, simplex: Meloidogyne hapla
2a On inflorescences, flowers or fruits => 17
2b On stems, shoots and leaves => 3
3a Malformations mainly on stem, or usually involving many severely stunted leaves, clustered at shoot tips, or extending over many leaflets of largely disfigured leaves => 12
3b Galls mostly on unfolded leaves; locally restricted, usually wart- or spindle-shaped. Caused by fungi => 4
4a Galls several mm long, in the leaf blades ± rotund, protruding on underside; on leaf veins, -midrib, -stalk, or flower parts spindle-shaped to oblong-oval. Bulges with sori of black telia or with densely positioned, yellowish aecia => 5
4b Galls wart-shaped, multi-cellular, up to 1 mm long, golden-yellow; single or ± coalescing, usually on underside of basal leaves, also on axis, stalks and basal stem parts. T. alpinum, flavum, lucidum, simplex, squarrosum: Synchytrium aureum
5a Bulges on leaves usually downwardly arched and predominantly only there bearing aecia; on upper side usually ± depressed, partially bearing spermogonia, often ± crimson to violet-red margined => 6
5b Sori on leaf underside, also on stem; of variable size, often conspicuous, slightly arched, black, weakly glossy, compact. T. alpinum: Puccinia rhytismoides
6a Aecia densely positioned, in smaller or larger groups on underside of ± arched bulges. Several, especially biologically different rust fungi, alternating on grasses, indistinguishable by their galls and usually also by the microscopic morphology of their aecia => 8
6b Aecia positioned loosely => 7
7a Aecia positioned on expanded, thickened, often dark violet discoloured spots, usually on both sides. Peridium usually with deflected border. Spermogonia develop rarely. T. alpinum: Puccinia septentrionalis
= On same host, with similar distribution, alternating on Agrostis, the rust fungus Puccinia recondita develops only in low number (8–12) in dense groups on underside leaf; aecia occur on discoloured, not noticeably thickened spots.
7b Aecia on often yellow-brown discoloured, hardly swollen leaf spots, protruding on underside, associated with honey-coloured spermogonia, developing on both sides. Peridium cup-shaped, with deflected, lacerate border. T. foetidum: Puccinia thalictri-koeleriae
8a Frequent fungi with aecia on several Thalictrum species => 11
8b More locally recorded fungi, which develop aecia on only a few species => 9
9a Aecia with several Thalictrum species as main host => 10
9b Aecia on T. foetidum as main host; in rounded groups on leaf underside, also occurring on fruits and in elongated patches on disfigured leaf midrib, -stalk and stem. Peridium cup-shaped or ± cylindrical, with lacerate white border: Puccinia thalictri-distichophylli
10a Aecia with cup-shaped or funnel- to tube-shaped peridium, at maturity with deflected, ± frayed border. T. aquilegiifolium, foetidum, minus: Puccinia poae-nemoralis
10b Aecia not further described, on T. aquilegiifolium, minus: Puccinia elymi
11a Aecia in smaller or larger groups on slightly thickened spots, often violet-brown on upperside, on underside yellowish and usually brown-bordered. Peridium cup-shaped, with deflected, frayed border. Thalictrum spp.: Puccinia alternans
11b Aecia and the often conspicuous spermogonia, positioned in a circle, usually developing on upperside on often distinctly swollen pads. Peridium whitish or yellowish with deflected, irregularly serrate or slightly fringed border. T. flavum, minus, simplex: Puccinia recondita species complex
12a Differently furnished malformations caused by animal parasites => 14
12b Malformations bearing early brown sori or exhibiting at first ± lead-grey bulges, with dusting of black spores later on => 13
13a Lead-grey swollen bulges, occurring on the often largely stunted leaf blades especially on venation protruding on both sides, often also on the ± bent leaf-midrib, -stalk, on stems and even flower parts. At first closed, later on erupting and with black dusting. Thalictrum spp.: Urocystis sorosporioides
13b Mycelium perennial, the developing host organs changing considerably. Shoots with lanky, elongated internodes, developing faster than normal ones. Leaf axis squat, leaf blade narrower and pale, diseased parts bearing many dark-brown telia. Thalictrum spp.: Tranzschelia anemones
14a Mainly curling or slightly swollen malformations of ± stunted leaves => 15
14b Leaflets curled, margin folded upwards, forming a subglobular gall of variable size. Containing several reddish larvae. T. speciosissimum: Dasineura bragancae
15a Malformations not conspicuously pubescent => 16
15b Up to 10 mm long, bud-like clustering of markedly stunted, ± whitish haired leaves on tips of main- and side shoots or in stunted axillary buds on the longitudinal growth. Larvae glossy red. T. aquilegiifolium, flavum, minus, simplex: Jaapiella thalictri
16a Malformations of terminal leaves and possibly of neighbouring inflorescences caused by midges or aphids => 17
16b Leaf blades of usually basal leaves on the ± stunted midrib converging. Leaflets shortened, mostly spoon-like, converging, thickened, strongly rugose and curled. T. flexuosum, minus: Phyllocoptes jaapi
16c A few internodes of apical part of stem stunted, bent when infestation is one-sided. Leaves and sometimes stem of the similarly stunted and disfigured inflorescence variously clustered. Leaf blades ± converging, curved and curled, dark green close to infestation site. Thalictrum spp.: Philaenus spumarius
17a On inflorescences or single flowers => 18
17b Fruit distinctly swollen, globular or acuminated, egg-shaped, up to 5 mm long, seeds absent; wall succulent, thickened; gall in dry condition ribbed. Containing one or two yellow larvae. T. aquilegiifolium, flavum, lucidum, minus incl. subsp . majus, simplex, speciosissimum: Ametrodiplosis thalictricola
18a Malformation of inflorescence or galls on single or clustered flowers; caused by animal inducers => 19
18b Expanded or localised malformations in the axis of the panicle, flower peduncles or perianth leaves caused by fungi => 5
19a Single flowers globularly swollen, stamens and especially anthers little developed; sometimes on shortened stalks and axis of panicle with several clustered in the otherwise normally flowering or already fruiting inflorescences. Larvae glossy red. T. aquilegiifolium, flavum, minus, simplex: Jaapiella thalictri
19b Inflorescence markedly stunted, densely occupied by disfigured, ± greened flowers. T. aquilegiifolium, alpinum, delavayi, flavum, lucidum, minus: Aphis thalictri
Laatste bewerking 1.v.2020
Dichotomous table for gallers on Thlaspi
1a On parts above ground => 4
1b On root collar or on roots => 2
2a On roots => 3
2b Rotund swellings on root collar, up to 6 mm long one-chambered. Containing a single larva. T. arvense, Noccaea perfoliata: Ceutorhynchus assimilis
2c Rotund root collar galls, 3–5 mm long. Noccaea perfoliata: Ceutorhynchus carinatus
3a Conspicuous, spindle-shaped or cylindrical thick-succulent compact galls, often more than 10 mm long, on main- and side roots, often in smaller sizes on secondary roots. “Clubroot”. Thlaspi spp.: Plasmodiophora brassicae
3b Roots often with many slender, 2–4 mm long cylindrical swellings, provided with several lateral roots. T. arvense, Noccaea brachypetala: Meloidogyne hapla
= Cyst eelworms, both Heterodera cruciferae and H. schachtii have been reported from T. arvense
4a Malformations of indefinite shape extending over several organs or localised to extensive malformations caused by fungi fruiting at surface, sori of which usually occur simultaneously on several organs => 8
4b Locally definite galls of rather similar shape on single organs => 5
5a On inflorescences, flowers or fruits => 17
5b On stems or leaves => 6
6a Galls conspicuous, spindle-shaped or globular => 7
6b Galls wart-shaped, less than 1 mm across, usually many on the underside of basal leaves. Sometimes ± coalesced crust-like; also on petioles and basal parts of young stems. T. rotundifolium: Synchytrium infestans
7a Galls ± globular to acuminated, spindle-shaped, about 5–6 mm long. Containing a single larva. Noccaea perfoliata: Ceutorhynchus carinatus
7b Spindle-shaped glabrous galls, about 20–25 (35) mm long, usually on all sides of stems, sometimes almost node-like, on petioles or midrib ± flattened; especially on leaves also deep green inside; partially with rather long tunneled channels. Containing a single larva. T. arvense, Noccaea brachypetala, perfoliata: Ceutorhynchus chalybaeus
8a On the malformations develop white or brown fruiting bodies of fungi => 14
8b Malformations caused by animals => 9
9a The animals develop outside on the galls, partially distinctly visible, partially hidden by the malformation => 10
9b Young plants largely stunted. Hypocotyls, petiole, and leaf blade base shortened, pale green, spongy. Neighbouring shoots severely stunted and thickened. Later infected stems are swollen over different lengths on one- or all sides, shortened, occasionally bent. Galls at surface undulately wrinkled, ± necrotic, with many eelworms inside. Thlaspi spp.: Ditylenchus dipsaci
10a Malformations caused by aphids or spittlebugs => 12
10b Malformations caused by larvae of gall midges => 11
11a Leaves terminally or laterally on stunted shoots, also in axillary buds ± tuft-like clustered, stunted, thickened at base and discoloured. Primordia of inflorescence are included in the gall, or display densely clustered, severely disfigured buds. Between the organs develop whitish or yellowish-white, jumping larvae. T. arvense: Contarinia nasturtii
11b Shoot tip disfigured. T. montanum: Unidentified gall midge
12a Malformations caused by aphids => 13
12b Young stems stunted and bent over a few internodes. Inserted leaves stunted, ± nest-like converging, undulately curled, locally dark green. T. arvense, Noccaea brachypetala: Philaenus spumarius
13a Tips of vegetative or generative shoots stunted; organs clustered, severely stunted. Aphid 1.5–2 mm long, grey-green to grey-yellow, siphunculi yellow, twice as long as the oblong yellow-green cauda. T. arvense: Lipaphis erysimi
13b Similar malformations, mainly restricted to the tips of shoots or inflorescences on severely disfigured leaves and flower buds, and on fruits and younger parts. Aphid 2–2.5 mm long, yellow-green, with 2 longitudinal rows of small black cross stripes; densely grey powdered; siphunculi short, swollen, brownish-black, about as long as the oblong, dark-green cauda. T. arvense: Brevicoryne brassicae
14a Sori white; infestation very variable, often without distinct malformations => 15
14b Mycelium disfigures the infected shoots completely or in the terminal parts, which bear smaller, thickened, paler leaves and which usually remain sterile. Exceptionally developing flowers are largely disfigured and ± greened. On expanded parts mainly of the leaf undersides develop many punctiform sori with rust- to dark-brown telia. T. alliaceum, arvense, “bulbosum”; Noccaea spp.: Puccinia thlaspeos
15a The sori protruding from the malformations consist of branched conidiophores => 16
15b Sori consist of dense pads, at first closed, glossy, porcelain-like, later on rupturing and with mealy dusting, usually with several, which are rotund on leaf blade underside, ± oblong oval to spindle-shaped and occasionally bent on leaf veins, – stalks and stem parts. T. arvense; Noccaea caerulescens, perfoliata: Albugo candida
16a Infected stem parts pale green, hypertrophied and ± distorted; sometimes slightly swollen during the development of infected leaves. On infected axial parts inserted organs, especially flower buds, severely stunted; diseased siliques usually crippled, occasionally enlarged and swollen. T. arvense: Hyaloperonospora thlaspeos-arvensis
16b On Noccaea brachypetala, caerulescens, causing similar damage: Peronospora thlaspeos-alpestris
16c Similar malformations on Noccaea perfoliata: Hyaloperonospora thlaspeos-perfoliati
17a Galls on single or several flowers or fruits => 18
17b Internodes of inflorescence distinctly shortened. Buds, flowers or young siliques clustered. Flowers partially ± greened. T. arvense: Thrips tabaci
18a Malformations usually inconspicuous, without involvement of other organs, on older ovaries or fruits => 20
18b Flower galls => 19
19a Already largely developed, single or sometimes clustered flower buds strongly swollen, almost globular. Larvae inside the organs or also between densely clustered flower buds; white to pale yellow, jumping. T. arvense; Noccaea brachypetala, caerulescens: Contarinia nasturtii
19b Calyx of opened flowers strongly hypertrophied. Corolla and the broadened stamens ± greened. Ovary severely disfigured, narrowed and elongate. Locally oblong-oval white sori on the diseased organs. T. arvense; Noccaea caerulescens, perfoliata: Albugo candida
20a In largely developed shoots, not or only slightly swollen, develop ivory white to lemon yellow coloured, jumping midge larvae. T. arvense: Contarinia thlaspeos
20b In the seed primordia of hardly disfigured fruits develop yellow-brown to grey-violet spore masses. Noccaea brachypetala, caerulescens, crantzii: Thecaphora thlaspeos
Laatste bewerking 1.v.2020
Dichotomous table for gallers on Convolvulus
1a On parts above ground => 2
1b Roots with small nodular to spindle-shaped swellings. Convolvulus sp.:
Meloidogyne hapla
2a On shoots and leaves => 3
2b vary, and also capsules, in usually conspicuously smaller flowers hardly changed; sometimes remarkably narrowed in apical part; anthers almost always sessile, swollen, at first like the nectar ring temporarily bearing whitish to yellowish sori containing conidia. Spores in balls, pale brown-red; mainly in several or all, at first slightly swollen, later on aborted seed primordia. Convolvulus arvensis, Calystegia sepium, soldanella: Thecaphora seminis-convolvuli
3a Malformations caused by aphids, psyllids or spittlebugs => 7
3b Malformations caused by different inducers => 4
4a Galls caused by parasitic animals => 5
4b Usually aecia arranged in a circle on the underside of undisfigured leaves. Sori on veins, stalks and axial shoot parts sometimes slightly swollen. Convolvulus spp.; Calystegia spp.: Puccinia convolvuli
4c Stems with a white cover, at first shiny, later powdery. Parts of the plant may become disfigured. C. pentapetaloides, siculus, tricolor: Albugo convolvulacearum
5a Malformation of many terminal leaves => 6
5b Shoots or petioles with ± expanded swellings on all- or one-side, pale green, spongy, on surface ± wrinkled. Leaves ± distorted. Convolvulus arvensis: Ditylenchus dipsaci
6a Terminal shoots or plant completely and severely stunted, axial parts shortened; leaf blades folded upwards, variously curved and rolled loosely, swollen, yellowish or crimson discoloured, abnormally, ± densely pubescent. Convolvulus althaeoides, arvensis, cantabrica, thunbergii: Aceria convolvuli
6b Similar, but glabrous malformations usually without distinct stunting of shoots, on loosely arranged, ± erectly folded and sickle-shaped disfigured leaves. Convolvulus arvensis: Aculus convolvuli and or Aceria malherbae, the latter also on Calystegia sepium
7a Malformations of often numerous leaves on shoots. Caused by aphids => 8
7b Leaves on the distinctly shortened terminal internodes clustered and stunted, with several converging ± nest-like; leaf blades partially distorted and deep green. Contain a froth-covered nymph. Convolvulus arvensis, Calystegia sepium: Philaenus spumarius
7c Pustule, 2 mm across, protruding on both sides of leaf blade, with exit hole on leaf underside, surrounded by white hairs. Convolvulus canariensis: Unidentified psyllid
8a Leaves folded, partially rolled, ± curled; contain black aphid. Convolvulus arvensis, Calystegia sepium: Aphis fabae
8b Leaves curled, curved downwards. Aphid green. Convolvulus arvensis, Calystegia sepium: Myzus persicae
Laatste bewerking 24.viii.2020
Dichotomous table for gallers on Camelina
1a On parts above ground => 3
1b On root collar or on roots => 2
2a Root collar with about 6–8 (10) mm long, rotund, often one-sided, succulent, one-chambered galls. Containing a single larva. C. microcarpa, sativa: Ceutorhynchus assimilis
2b Roots with conspicuous spindle-shaped or acuminated, cylindrical, thick fleshy compact swellings of variable size. Camelina spp.: Plasmodiophora brassicae
3a On inflorescences, flowers or fruits => 9
3b On vegetative parts => 4
4a Malformations bearing white fungus sori at surface => 8
4b Malformations caused by animal parasites => 5
5a Inducers inside malformations => 7
5b Leaves on ± stunted shoots clustered, stunted, deflected, sometimes twisted => 6
60a Aphid 2–2.5 mm long, yellowish-green, densely grey powdered. C. alyssum, microcarpa, sativa: Brevicoryne brassicae
6b Aphid 1.5–2 mm long, pale yellowish to yellow-green, not powdered. Camelina spp.: Brachycaudus helichrysi
7a Stems, also leaf axis, with swellings up to about 15 mm long, spindle-shaped. Containing a single larva. C. alyssum, sativa: Ceutorhynchus chalybaeus
7b Stem of young plants severely stunted, spongy, pale green, wrinkled at surface; leaves often considerably stunted, galled from midrib onwards, especially the basal part. Infestation of older plants results in spongy, ± expanded, pale-green, often curved bulges on stems or similar malformations encroaching onto the leaf blades. C. microcarpa, sativa: Ditylenchus dipsaci
8a Fungus sori dense, at first closed, glossy, porcelain-like, later on mealy dusted; their vicinity hardly discoloured, on underside leaf blade rotund, often non-cecidogenic; on midrib and shoot axis elongate oval, often in 2–15 mm long bulges, sometimes curved. Camelina spp.: Albugo candida
8b Malformations expanded, with loose, whitish down of branched conidiophores. Infestation site pale green; on younger leaves often arched upwards. Expanded infestation of young shoots results sometimes in conspicuous thickenings and bendings of stems, as well as to stunting of pale green leaves with margins deflected, slightly thickened and ± brittle. Camelina spp.: Hyaloperonospora camelinae
9a On ± expanded parts of inflorescence or on flowers => 10
9b Silique ± disfigured, soon maturing; inside are several white larvae. C. sativa: Dasineura napi
10a Flowers greened. Axis of inflorescence stunted, sometimes together with neighbouring stem parts. Leaves thickened at margin, rolled downwards, abnormally pubescent. C. microcarpa, sativa: Aceria drabae
10b Inflorescence ± severely stunted, axis sometimes thickened. Flower buds ± densely clustered, swollen. Larvae whitish to pale yellow, jumping. Camelina spp.: Contarinia nasturtii
Laatste bewerking 30.iv.2020
Dichotomous table for gallers on Armoracia
1a On parts above ground => 4
1b On roots and root collar => 2
2a On root collar => 3
2b Side roots with usually 4–6 mm long, slender, spindle-shaped succulent swellings. Inside the galls cells contain masses of minute spores. Plasmodiophora brassicae
3a Rotund, up to 8 mm long one-chambered galls with a glabrous surface, contain a curved larva. Ceutorhynchus assimilis
3b Proliferations of conspicuous bulging, at surface ± subdivided, up to almost fist size galls, ± one-sided attached to the plant part. Agrobacterium tumefaciens
4a On flowers => 9
4b On stems or leaves => 5
5a Malformations caused by animals => 6
5b eaves on the underside with dense, rotund pads, sometimes in large numbers, rotund on the leaf blades, on the veins bulging, at first glossy, porcelain-like, later opening with mealy dusting of white sori. Albugo candida
5c Leaves somewhat disfigured with pale spots on the upperside, that correspond with a fungal bloom on the underside, consisting of erect, apical strongly branched conidiophores. Hyaloperonospora cochleariae
6a Galls predominate on petioles, leaf veins or on stems => 8
6b Malformations on expanded plant parts or on leaves => 7
7a Basal leaves of young plants loosely deflected over their length, ± curled. Many black aphids on underside. Inducer unidentified – ? aphid
7b Stems of younger main- or side shoots stunted, sometimes curved, leaves deflected, curled, their margins rolled inwards. Inflorescences stunted, flowers densely clustered ball-like. Contain a froth-covered nymph. Philaenus spumarius
8a Galls spindle-shaped, on leaves mainly on underside, 15–25 mm long, glabrous, also green inside, on midribs, petioles, more rarely on rather young stems. Containing a single larva. Ceutorhynchus chalybaeus
8b Spongy, at surface undulate-wrinkled, pale green swellings of variable length on stalks and lower part of midrib of basal leaves. Ditylenchus dipsaci
9a Flower buds strongly swollen, ± globular, about 5–7 mm across, unopened. Several, mainly yellow, non- jumping larvae. Dasineura armoraciae
9b Galls similar, but more slender and smaller, 2–4 mm long. Larvae whitish to pale yellow, jumping. Contarinia nasturtii
Laatste bewerking 30.iv.2020
Dichotomous table for gallers on Alyssum
1a On parts above ground => 4
1b On roots or root collar => 2
2a On roots => 3
2b Root collar with rotund succulent, one-chambered swelling, up to 8 mm long. Contains a single larva. A. alyssoides: Ceutorhynchus assimilis
3a Galls ± rotund, up to 5 mm long, succulent, many on side roots. A. montanum: Meloidogyne hapla
3b Main- and side roots with conspicuous, spindle- to barrel- shaped, succulent swellings. Inside many cell masses with minute spores. Alyssum spp.: Plasmodiophora brassicae
4a Malformations with white pads caused by fungi => 10
4b Malformations caused by animals => 5
5a On inflorescences or flowers => 9
5b On vegetative parts => 6
6a Stem with localised swellings. Galls with midge larvae inside or containing causers in rimmed depressions => 7
6b Young shoots ± stunted and arched; leaves clustered; often nest-like deflected; close to the froth-covered nymph ± deep green discoloured. Alyssum spp.: Philaenus spumarius
7a Larvae are inside gall => 8
7b Stem bulging over variable length, variously distorted, outside with single or several rimmed depressions containing a scale insect. Alyssum spp.: Planchonia arabidis
8a Terminal part of stem stunted, transformed into a 10‒15 mm long, 6–8 mm wide gall. Leaves densely clustered, swollen at base. A. alyssoides, gmelinii, murale: Janetiella fallax
8b Shoot with up to 4 mm long, about pea-size, spindle-shaped swellings. A large chamber contains several red larvae. A. alyssoides, montanum: Dasineura alyssi
9a Inflorescence disfigured over a substantial part. Flowers greened and/or leafy; abnormally white pubescent. A. alyssoides, hirsutum, Ptilotrichum halimifolium, tortuosum: Aceria drabae
9b Flowers swollen, unopened. Containing a single larva. Aurinia saxatilis: Unidentified gall midge
= The gall midge Dasineura auriniae is described from swollen flower buds of Aurinia petraea.
10a Rotund to oval, several mm long, at first closed, glossy, porcelain-like ± swollen bulges on stems and leaves. Later on with mealy dusting of closely arranged conidiophores. Alyssum spp.: Albugo candida
10b Leaves often distorted, usually with several, solitary or clustered, little wart- to bulge-like swellings on upper side, more rarely on underside. In the cavities branched conidiophores make narrow erinea. Sometimes expanded covers on bulging midribs or variously disfigured flowering or non-flowering shoots. Alyssoides utriculata; Aurinia saxatilis: Hyaloperonospora galligena
Laatste bewerking 29.iv.2020
Dichotomous table for gallers on Rorippa
1a On parts above ground => 3
1b On roots or on root collar => 2
2a Roots with expanded spindle- to barrel-shaped succulent swellings, ± bulging. “Clubroot”. R. austriaca, islandica, sylvestris: Plasmodiophora brassicae
2b Globular, pea- to cherry sized succulent galls on root collar, occasionally clustered. R. amphibia, islandica: Ceutorhynchus assimilis
3a On shoot tips, leaves, inflorescences or flowers => 6
3b Galls mainly or only on shoot axis => 4
4a Galls expanded, of very variable shape => 5
4b Axis with spindle-shaped, 10–15 (30) mm long, usually deep green swelling. Containing a single larva. R. amphibia: Ceutorhynchus chalybaeus
5a Youngest shoot parts swollen over ± extended length, soon covered with a loose, white down of branched conidiophores. R. amphibia, austriaca, islandica, palustris, sylvestris: Hyaloperonospora rorippae-islandicae
5b Young parts of non-flowering or flowering shoots with elongate bulges, at first glossy-white porcelain-like, later on with mealy dusting, sometimes coalescing into larger clusters, also curved swellings. Rorippa spp.: Albugo candida
6a On leaves, inflorescences or flowers => 8
6b On the tip of shoots, developing leaves or inflorescences => 7
7a Tip of main- and side shoots, also axial buds transformed into spongy, whitish, coalescing masses; the neighbouring, partially normally developed organs densely clustered, basal parts of petioles or flower buds variously swollen close to the gall. Sometimes the inflorescence galls are overtopped by some atrophied flowers. Containing several yellow- to orange-coloured larvae. R. amphibia, x anceps, austriaca, palustris, pyrenacia, sylvestris & subsp. kerneri: Dasineura sisymbrii
7b Longitudinal growth of axis stunted. Leaves or all parts of infected inflorescence clustered. All parts at base ± succulent, but not swollen and spongy, gall very variable. Containing several whitish- to lemon yellow, jumping larvae. R. palustris, pyrenaica, sylvestris: Contarinia nasturtii
8a On inflorescences or flowers => 13
8b On leaves => 9
9a Galls caused by animals => 12
9b Galls caused by fungi => 10
10a Sori white => 11
10b Leaves, also stem, with rotund, dull brown to black warts, or petioles with oblong, up to 1.5 mm long, bulge-like swellings; organs if strongly infected ± curved. R. amphibia: Physoderma vagans
10c On the same host the very similar punctiform, rotund, nodular protruding swellings on leaf blades or in flat brown bulges on petioles are attributed to Physoderma magnusianum
10d Small hard gregarious pustules, less than 0.5 mm across. Rorippa spp.: Synchytrium aureum
11a Leaf midrib, also stalks and venation, with spindle-shaped bulges. Leaf blade with ± rotund, pale green swellings. Sori at first closed, white and glossy, porcelain-like, then with dusting. Rorippa spp.: Albugo candida
11b Largely similar malformations, covered with loose down of conidiophores. R. amphibia, austriaca, islandica, palustris, sylvestris: Hyaloperonospora rorippae-islandicae
12a Basal leaves stunted. Midrib shortened, leaf blade ± nested, dark green, bent or rolled upwards. Strongly infected plants do not flower. R. amphibia: Aphis triglochinis
12b Leaves deflected over their top. Variously distorted and ± curled; sometimes the axis is stunted on one side and bearing several clustered disfigured leaves Rorippa spp.: Philaenus spumarius
13a Galls restricted to flowers => 15
13b Malformations on other parts of inflorescence => 14
14a Upper leaves disfigured. R. austriaca: Unidentified gall mite
14b Axis stunted. Flowers clustered, aborted. R. sylvestris: Aphis gossypii and/or Aphis nasturtii
15a Flowers unopened, often reddish discoloured on the outside, ± spongy thickened; stalk sometimes slightly elongated, resulting in a deflected gall. R. x anceps: Unidentified gall midge
15b Flowers swollen, ± egg-shaped, unopened. Corolla absent. Stamens short, thickened; ovary thickened. Containing several whitish- to pale yellow jumping larvae. R. palustris, pyrenaica, sylvestris: Contarinia nasturtii
Laatste bewerking 28.iv.2020
Dichotomous table for gallers on Torilis
1a Malformations on inflorescences or their parts, or fruit galls => 7
1b Malformations on leaves or stems => 2
2a Leaves with expanded malformations => 4
2b Vitreous bulges or pads bearing fruiting bodies on leaves, -stalks, or on stems => 3
3a Spindle-shaped, vitreous bulges on basal stem part, on petioles, midrib and leaf veins. T. japonica: Protomyces macrosporus
3b Bulges yellowish, soon bearing aecia, on the axis of leaves, also on younger stem parts. T. arvensis & subsp. neglecta, japonica, nodosa: Uromyces lineolatus
3c T. japonica has furthermore been indicated as host for Puccinia chaerophylli
4a Malformations caused by aphids or spittlebugs => 5
4b Tip of leaflets variously rolled or strongly curled. T. arvensis, japonica: Aceria peucedani
5a Malformations caused by aphids => 6
5b Main- and side midrib, together with ± curled leaflets, strongly deflected; usually with several similarly disfigured leaves changed into a nest-like cluster. T. arvensis, japonica: Philaenus spumarius
6a ip of leaflet at first with small, upwardly open folds; causer also in ± swollen leaf sheaths. The side shoots that develop later in these sheaths curled; the umbels ± greened and/or leafy. T. arvensis, japonica: Hyadaphis foeniculi
6b Leaflets densely clustered on ± shortened midrib, disfigured; leaf blades irregularly deflected, twisted, curled and ± bulging. T. arvensis, japonica: Semiaphis anthrisci
7a Extensive malformations on inflorescences => 9
7b Localised galls on fruits or stalks of inflorescences => 8
8a Centre of umbel or stalk of umbel ± swollen, club-shaped. Inner wall, rough, covered with mycelium. Containing a single red larva. T. japonica: Lasioptera carophila
8b Fruit inflated, bladder-like; ± globular or flattened on one side, oblong-oval. Gall thin-walled sometimes reddened, protruding above the umbel. Containing 1 (–3) orange-red larvae. T. japonica: Kiefferia pericarpiicola
9a (Partial) umbels severely stunted; ± ball-like clustered; aphid galls => 10
9b Flowers in umbel clustered with umbel stalk often little stunted, variously leafy or only partially greened. T. arvensis, japonica: Aceria peucedani
10a Stalks of umbels and flowers often variously stunted, resulting in irregularly stunted parts. Flower bud disfigured, often mostly greened or even leafy. T. arvensis, japonica: Semiaphis anthrisci
10b Similar malformations. T. japonica: Cavariella pastinacae
Laatste bewerking 28.iv.2020
Dichotomous table for gallers on Scrophularia
1a On inflorescences, flowers and fruits => 10
1b On vegetative organs => 2
2a Localised or extensive malformations mainly on leaves or terminally on higher placed parts of shoot => 5
2b Galls on lower or middle stem parts => 3
3a The causers develop inside the galls => 4
3b Stem with bulging swellings of different length, mainly close to ground, bearing on their surface several rimmed depressions containing a nymph. Scrophularia spp.: Planchonia arabidis
4a Young shoots close to ground, or also on higher placed parts of side shoots, completely or locally severely stunted, spongy, often conspicuously curved with wrinkled surface. Occasionally encroaching onto petioles and basal parts of ± disfigured leaf blades. S. nodosa: Ditylenchus dipsaci
4b Stem with localised nodular or spindle-shaped, variously distorted swelling. Gall wall browned inside. Leaves clustered at infestation; complete plant ± disfigured. S. nodosa: Cause unknown – ? insect
5a Wart-shaped galls or expanded, variable malformations caused by fungi => 8
5b Malformations caused by animals => 6
6a Single or many leaves with bladder-like swellings or curls => 7
6b Leaves clustered, rosette-like; leaf blades thickened. S. umbrosa: Unidentified gall midge
7a Leaves stunted, with bulging reddened swellings. S. nodosa: Unidentified ? thrips
7b Leaf blade curled, strongly bent downwards at infestation, there deep green. Internodes ± stunted if infected, resulting in clustered ± curled leaves. S. umbrosa, nodosa: Philaenus spumarius
8a Malformations of undefined extent => 9
8b Galls wart-shaped, multi-cellular, less than 1 mm across, ± golden-yellow. Usually many on underside of basal leaves; also on petioles and young stems; sometimes joined into crusts or ridges. S. nodosa, umbrosa: Synchytrium aureum
9a Leaf blades on hardly swollen, rotund to widely expanded spots with usually yellow or reddish bordered sori of fungus. On main veins, petioles and stems developing sori more strongly thickened; bulges of variable size; diseased leaves and stems often severely distorted. At first with spermogonia and aecia, soon also bearing telia. Scrophularia spp.: Uromyces scrophulariae
9b Completely diseased young shoots at first develop faster and firmer than healthy ones, remaining lanky and bear pale-green leaves with narrowed, slightly thickened leaf blades, which are soon covered with a down of branched conidiophores on underside. S. nodosa, scopolii, umbrosa: Peronospora sordida
10a Flower or inflorescence galls => 11
10b Fruit slightly swollen and disfigured only if infected in right phase. Usually containing a single larva. Scrophularia spp.: Rhinusa tetra
11a Flower galls => 12
11b Inflorescence curved; terminal leaves curled. Flower buds contain several at first white, later on orange coloured larvae. S. nodosa, scorodonia: Macrolabis scrophulariae
12a Flowers strongly swollen, unopened. Calyx slightly changed; corolla thickened, especially the tube; stamens with thickened filaments transformed into irregular, leaf-like organs. Ovaries swollen; inner wall covered with dirty white mycelium. Containing a single yolk-yellow larva. S. canina, decipiens, grossheimii, nodosa, umbrosa: Asphondylia scrophulariae
12b Flowers swollen, globular, usually unopened. Stamens and pistil enlarged. Larvae live between flower parts, white to lemon-yellow, jumping. S. auriculata, canina, nodosa, schousboei, umbrosa: Contarinia scrophulariae
Laatste bewerking 28.iv.2020
Dichotomous table for gallers on Scorzonera
1a On above-ground parts => 4
1b On roots or root collar => 2
2a Considerable galls on root collar => 3
2b Roots with elongated spindle-shaped swellings, up to 5 mm long, bearing some lateral roots. Coalescing in rows in cases of heavy infestation. S. hispanica: Meloidogyne hapla
2c Lateral roots terminally thickened, ± curved, longitudinal growth stunted, prematurely shrivelled. Whole plant becoming stunted. S. hispanica: Paralongidorus maximus
3a Uniformly succulent, up to walnut size, ± rotund-ovoid proliferation on root collar, sometimes on root- and stem parts close to the surface. “Crown gall disease”. S. hispanica: Agrobacterium tumefaciens
3b Almost globular, glabrous, one-chambered swellings on root collar. Often several variously coalesced, depending upon the number of galls, to form crook-backed structures. One larva per chamber. S. humilis: Aulacidea hieracii
4a On capitula or flowers => 13
4b On stems or leaves => 5
5a Malformations on leaves => 6
5b Stems with conspicuous, crooked swellings at the surface mostly on all sides, 40–60 mm long, about 10 mm thick. Inside the stem are many, clustered rotund galls, each about 2 mm long, and each with one larva. S. austriaca, hispanica, humilis; Podospermum purpureum: Aulacidea scorzonerae
6a On leaf blades or leaf veins => 7
6b Leaf sheaths ± bladder-like swollen and discoloured. Enclosed shoot stunted, with severely stunted development. S. hispanica: cf. Brachycaudus tragopogonis
7a Malformations caused by superficial sori => 11
7b Galls with living animal inducers inside => 8
8a Galls predominantly on the leaf blade or on the secondary veins => 9
8b Midrib on the underside often with several galls, in loose or more clustered constellations appearing pale green, rotund-ovoid, 2–3 mm long, one-chambered. Containing a single larva. S. austriaca, hispanica, humilis; Podospermum purpureum: Aulacidea scorzonerae
9a Galls of definite shape; surface glabrous, usually ± reddened. Midge galls => 10
9b Flat, pale green, ± spongy, rugose galls, especially swollen at the veins and extending over at least 15 mm in length on the leaf blade, ± curved as result of the infestation. S. hispanica: Ditylenchus dipsaci
10a Leaf blade with round pustules, several millimetres wide; bulging on the upperside, yellowish or dirty crimson-red, sometimes surrounded by a reddish discoloured area; the underside lighter, flat. A pale orange-yellow larva. S. austriaca, humilis: Cystiphora scorzonerae
10b Elevated, elongated to spindle-shaped galls, up to 5 mm long, protruding from both leaf surfaces, often yellow or reddish bordered. Often many per leaf blade, the longitudinal stem predominantly situated in a secondary vein and extending on both sides on the leaf blade. Containing a single larva. S. humilis: Unidentified gall midge
11a Malformations with sori of true rust fungi (Uredinales) => 12
11b Oomycetes. Sori oblong-oval, initially closed and porcelain-glossy, white, opening later and with mealy dusting. S. austriaca, hispanica, humilis, parviflora; Podospermum canum, laciniatum; Scorzoneroides autumnalis, helvetica: Pustula obtusata
11c Oomycetes; upperside of the leaves with yellow or brown spots; on the underside a greyish brown fungal down consisting of erect, distally several times branched conidiophores; the final branches ending in an ovoid conidium. S. hispanica, humilis: Novotelnova scorzonerae
12a The primary uredomycelium usually pervades the whole host, whose parts are paler, more lanky or deformed in another way. Spores brown. Podospermum purpureum, roseum; S. austriaca, hirsuta, hispanica, humilis, mollis, papposa: Puccinia scorzonerae
12b Shoot etiolated by the expanded aecial mycelium. Leaves in case of heavy, infection, usually one-sided, conspicuously curved or even twisted. Aecia cup-shaped, later opening with frayed border, widely dispersed over leaves, stems and involucres; yellowish. S. austriaca, hispanica, humilis; Podospermum purpureum, roseum: Puccinia jackyana
13a Malformations induced by insects => 14
13b Diseased capitula already stunted early in development, shortened, initially turgid. Flowers soon completely destroyed and replaced by a black-violet, sparsely dusting spore mass. Podospermum canum, puurpurum, roseum; S. aristata, calyculata, hispanica, humilis, mollis: Microbotryum scorzonerae
14a Receptacle of the unopened flower head ± egg-shaped, swollen. In case of one-sided infestation ± curved. Usually containing one larva. Podospermum purpureum; S. parviflora; Scorzoneroides autumnalis: Trupanea stellata
14b Capitula conspicuously swollen, rotund to elongated ovoid. Galls in the shortened and broadened fruits. Wall thick and woody. Pappus shortened, with withered corolla mounted on the gall. Often many galls per flower head. One yellowish-white larva per gall. Podospermum purpureum, roseum; Scorzonera humilis, parviflora: Aulacidea abdominalis
14c Base of flower head is usually enlarged; the conglomerate of galls lignified, hard. Larval chamber is round or slightly ovate, developing in seeds which are slightly swollen. Pdospermum purpureum, roseum; Scorzonera humilis, parviflora: Aulacidea abdominalis
14d A stem swelling-like gall, usually located under the flower head, sometimes in the lower part of the stem; spindle-like or cylindrical stem enlargement, 30‒60 mm long, 10 mm in diameter; the surface with longitudinal ribs, as on the stem, sometimes the ribs are waved and distance between them is larger, depending on the diameter of the gall. In a longitudinal dissection, single 2 mm long larval cells are visible which are located near one another. The number of larval cells is larger towards the periphery of the gall. The stem above the gall is shortened and the flower head terminates its development. S. austriaca, hispanica, humilis; Podospermum purpureum: Aulacidea scorzonerae
14e Galls induced in achenes. Podospermum laciniatum: Aulacidea laurae
Laatste bewerking 27.iv.2020
Dichotomous table for gallers on Satureja
1a On axial parts of shoots, shoot tips, swollen buds or leaves => 2
1b Flowers disfigured; calyx swollen; corolla, stamens and ovaries aborted. Clinopodium acinos, Micromeria graeca, Clinopodium vulgare: Unidentified gall mite
1c Flowers disfigured. Micromeria graeca: Aceria saturejae
1d Calyx inflated, flower disfigured or aborted. Micromeria graeca subsp. fruticulosa: Asphondylia sp.
2a Malformation of many leaves on shoot tips, terminally on shoots or single leaves => 6
2b Galls on axial parts of shoots, sometimes encroaching onto leaves => 3
3a Swollen buds contain solitary gall midge larvae. Clinopodium alpinum, nepeta subsp. glandulosum. Asphondylia calaminthae
3b Shoot axis and underside of leaves long-haired white-erineum. Inflorescence stunted, especially along venation. Clinopodium vulgare: Unidentified gall mite
4a Causers occur inside galls => 5
4b Stem ± spindle-shaped or bulging, with several rimmed, irregular depressions containing the inducer. Clinopodium acinos: Planchonia arabidis
5a Stem with rotund to acuminated, egg-shaped swelling, up to 5 mm long, tough- and smooth-walled. Containing a single lemon-yellow larva. Clinopodium acinos, vulgare: Squamapion vicinum
5b Complete plant stunted. Stem distinctly shortened, spongy, swollen. Side shoots of more developed plants and basal leaf parts similarly disfigured to varied extent. Satureja hortensis: Ditylenchus dipsaci
6a Malformation of many leaves on shoot tips or terminally on shoots => 8
6b Localised galls on leaves, sometimes on basal young shoots => 7
7a Galls less than 1 mm across, multi-cellular, wart-shaped, ± golden-yellow; usually many on leaf underside, sometimes on petioles. Clinopodium vulgare: Synchytrium aureum
7b Leaf blades with yellowish rotund pads, several mm long, on leaf underside; their surface bearing aecia. Similar, more spindle-shaped bulges on leaf veins and -stalks as well as on shortened basal parts of shoot axis, sometimes strongly swollen and distorted. Clinopodium spp.; Micromeria hyssopifolia, varia; Satureja hortensis, thymbra: Puccinia menthae
7c Lower leaves turn brown and wither. On the underside a purple fungal down, consisting of vertical conidiophores that apically several times are dichotomously branching, each branch ending in a globular conidium. S. hortensis: Peronospora saturejae-hortensis
8a Curling of leaves caused by aphids or spittlebugs => 9
8b Leaves and generative primordia on shoot tip severely stunted, accumulated, tuft-like; ± disfigured and densely white pubescent. Clinopodium acinos, vulgare: Unidentified gall mite
9a Malformations caused by aphids => 10
9b Some internodes of stem shortened, sometimes ± bent. Leaves ± clustered, with several deflected over their tips, ± distorted, converging, nest-like, containing a froth-covered nymph. S. hortensis, montana: Philaenus spumarius
10a Terminal part of shoot axis ± shortened; side shoots variously stunted. Leaves ± clustered, curled, ± rolled inwards and downwards. Clinopodium acinos, grandiflorum, menthifolium, nepeta incl. subsp. glandulosum, vulgare: Aphis calaminthae
10b Leaf blade curled. Clinopodium acinos, menthifolium, vulgare: Aphis clinopodii
10c Similar malformations on Clinopodium vulgare: Aphis nepetae
10d Similar malformations on Satureja hortensis: Unidentified aphid
10e eaf blade swollen. Aphid green or yellow. Clinopodium alpinum, nepeta subsp. glandulosum: Aphis origani
Laatste bewerking 27.iv.2020
Dichotomous table for gallers on Tragopogon
1a On plant parts situated higher above-ground => 4
1b On roots, root collars or basal stem parts => 2
2a Galls on root collar or on neighbouring stem parts => 3
2b Roots with bulging, chambered swellings. Each chamber containing one larva. T. porrifolius: Aulacidea hieracii
= On T. porrifolius the eelworm Meloidogyne hapla has been recorded
2c Swelling on roots of T. porrifolius, pratensis: Orellia falcata
3a Root collar or basal stem parts with one-chambered, rotund, sometimes isolated, one-sided, succulent tough-walled swellings, or galls often in groups or rows coalesced into ± bumpy tubercles or even into several cm long, irregular bulges. In each rotund- oblong-oval 1–1.5 mm long larval chamber is one whitish larva. T. dubius & subsp. major, porrifolius, pratensis & subsp. orientalis: Aulacidea tragopogonis
3b Conspicuous, 2.5–3.5 x 4–5 cm large, rotund to oblong-oval, succulent proliferations on root collar, undulate on the surface. T. porrifolius: Agrobacterium tumefaciens
4a On capitula, florets or achenes => 10
4b Localised or elongate malformations on leaves or shoots, sometimes extending into the green parts of the inflorescence => 5
5a Malformations with sporulating fungal sori on the surface => 9
5b Malformations caused by animal inducers => 6
6a Malformations predominantly developing on leaves => 7
6b On the base of the main stem, one-sided brown-yellowish multi-chambered swelling. T. dubius & subsp. major, porrifolius, pratensis & subsp. orientalis: Aulacidea tragopogonis
7a Inducers inside the galls => 8
7b Leaves sometimes ± twisted, curled; also the sheaths abnormally inflated. T. crocifolius, dubius, porrifolius, pratensis & subsp. orientalis: Brachycaudus tragopogonis
7c Malformations have been recorded caused by froth-covered nymphs. T. orientalis: Philaenus spumarius
8a Leaf blade with several slight swellings, separated from each other and therefore inconspicuous, about 1 x 2 mm long, situated between the veins. Each containing a larva. T. pratensis: Unidentified gall midge
8b Basal leaves with petioles and basal leaf blades distinctly shortened, pale green, in ± expanded areas swollen, spongy-undulate; other parts of leaf blade ± stunted. T. pratensis: Ditylenchus dipsaci
9a Shoots over large parts ± disfigured and etiolated, often remaining sterile. Leaves narrowed, ± shortened, pale green; like the stem occupied with many distantly, honey-yellow spermogonia and white margined, orange-red aecia. Infestation also occasionally extending into similarly deformed involucres and even into achenes. Tragopogon spp.: Puccinia hysterium
9b Similar malformations on T. dubius, porrifolius, pratensis & subsp. orientalis: Puccinia brachycyclica
9c Oblong-oval sori, initially closed and porcelain-glossy, later breaking open and with mealy dusting, occur rather often on all green parts and induce excessive branching and other malformations on early affected developing buds. Tragopogon spp.: Pustula obtusata
10a Malformations on capitula => 12
10b Galls on single or several florets, especially on achenes of capitula that look normal from the outside => 11
11a Basal part of the achene transformed into a mustard seed-like gall, large, thin- and hard-walled, one-chambered. Containing a single larva. T. pratensis: Unidentified gall wasp
11b chene spindle-shaped, swollen. T. pratensis: Unidentified gall midge
12a Capitula greened or disfigured by fungi which later produce dusting of spores => 15
12b Malformations caused by animal inducers => 13
13a Malformations caused by fly maggots or midge larvae => 14
13b Capitula remaining closed. Florets ± atrophied, embedded by a bladder-like malformation, swollen, conspicuously cornicular converging, one-sided enclosed by involucral bracts. T. pratensis: Cause unknown – cf. Brachycaudus tragopogonis
14a Capitula remaining closed; slightly swollen at base, variously disfigured and curved. Containing several whitish to yellow jumping larvae. T. dubius, pratensis: Contarinia tragopogonis
14b Hardly conspicuous, often one-sided malformation of the flower head caused by single larvae, usually living between the achenes. T. pratensis: Ensina sonchi
15a Developing capitula shortened, ± globular to broad oval, swollen. Flower parts soon to a large extent affected by blackish-dark violet discolouration, later with dusting of spore masses. Tragopogon spp.: Microbotryum tragopogonis-pratensis
15b Malformation and ± greening of all florets in a flower head. T. pratensis subsp. orientalis: Cause unknown – ? gall mite
Laatste bewerking 26.iv.2020
Dichotomous table for gallers on Taraxacum
1a On above-ground parts => 3
1b On root and root collar => 2
2a Roots with spindle-shaped to slightly nodular swellings, bearing isolated lateral roots. T. officinale: Meloidogyne hapla
2b Considerable tuft-like proliferations on root collar. T. officinale:
Agrobacterium tumefaciens
3a On inflorescences or capitula => 16
3b On leaves => 4
4a Exclusively or predominantly on petiole, midrib and main veins => 12
4b Extensive malformation, or localised galls on leaf blade => 5
5a Galls local, sometimes clustering into larger groups => 8
5b Leaf blade with extensive malformations of irregular composition => 6
6a Malformations caused by aphids or cercopids => 7
6b Leaf blade ± shrivelled, converging, curled, twisted or rolled upwards, roll may be haired; leaflets narrowed, margin sometimes lacerate. T. officinale: Aculus rigidus
6c Curled leaves, contain froth-covered nymphs. T. officinale: Philaenus spumarius
7a Leaf blades sometimes spirally twisted; contain dark brown aphids. T. officinale: Uroleucon taraxaci
7b Leaf blade curled, with bladder-like swellings. Aphid green. T. officinale: Aulacorthum solani
7c Little indentation of the leaf blade. T. officinale, palustre: Trioza dispar
8a Single galls more than 4 mm long => 11
8b Single galls smaller => 9
9a Leaf blades with many bulges or yellowish-white spots on the upper side caused by smut fungi => 10
9b Leaf blade on under-, more rarely on upperside, with many reddish-yellow to dark orange-red multicellular warts, up to 1 mm long; solitary or sometimes coalescing to expanded crusts. Also occurring on inflorescence stalks or even the involucre. T. officinale: Synchytrium taraxaci
10a Leaf blades with usually several rotund or irregularly margined, yellowish-green, later pale brownish spots, up to about 3 (4) mm across, sometimes slightly thickened. Containing yellowish spores. T. officinale: Entyloma picridis
10b Leaf blade often with many small protruding swellings on the upperside; containing flat larvae in the depressions on the underside. T. officinale, palustre: Trioza dispar
11a Leaf blade with flat circular blister, up to 5 mm across, usually several in a leaf; rim of gall becomes dark red or purple; containing a yellow-red larva under a translucent epidermis. T. campylodes, officinale: Cystiphora taraxaci
11b Swellings protruding on the leaf underside, bearing clustered yellow sporulating aecia; rotund to oblong-oval, up to about 10 (15) mm long, including the main venation, irregularly margined; often with yellowish or reddish discoloured rim. T. officinale: Puccinia dioicae
12a Galls glabrous, confined to the midrib or a main lateral vein; possible malformations of the leaf blade develop as secondary growth disturbances => 13
12b Spongy, soft swellings, visible on both sides, the surface undulate rugose, often pale green, sometimes ± reddened, extending variously from the mid- and lateral veins to the neighbouring, sometimes ± arched leaf blades. T. officinale: Ditylenchus dipsaci
13a Malformations remaining closed. Inducers inside the galls => 14
13b Swellings inconspicuous, ± elongate-oval, 2–3 mm long, predominantly bulging on the underside of the leaf; on the midrib with yellow rim; on the surface bearing 1-celled, brown spores. T. officinale: Puccinia hieracii
13c Minor bulges in the midrib caused by primary uredina, spermogonia lacking. T. officinale, serotinum: Puccinia taraxaci
14a Galls about 12 (15) mm long, causing localised swellings of the venation, predominantly on the central and apical part of the leaf blade => 15
14b Midrib swollen at the leaf base; swelling fading away into the central and apical part of disfigured leaf blade which is sometimes undulate in the galled area. Gall most prominent on the underside. A mining larva in the galled tissue, making a round exit hole which protrudes into the upper epidermis just before pupation. T. officinale: Phytomyza wahlgreni
15a Swellings abruptly discontinued; especially conspicuous on the underside, ± rotund to oblong-oval, about 2–6 mm across; often several partially or completely fused into a bulge up to 4 cm long; pale green or often reddened; soon tough-walled. individual swellings develop, each with one chamber and containing one white larva or pupa. T. officinale: Phanacis taraxaci
15b Galls gradually terminating, flat spindle-shaped, initially yellowish-green, later on reddened to dark brown, of very different size, 2‒7 (15) cm long; also on the sometimes strongly curved inflorescence stalks and main leaf venation; in case of abundant occurrence secondarily also disfiguring the leaf blade. With many, spores situated in and on the vascular bundles. T. officinale: Protomyces pachydermus
16a On inflorescence stalks => 17
16b On capitula. Receptacle of the externally often hardly disfigured flower head weakly swollen; containing a larva with conspicuous mandibles. T. officinale: Campiglossa producta
17a Swellings several mm long => 17
17b Single galls multicellular, only up to about 1 mm long, yellow- dark orange, sometimes additionally coalescing into disfigured, tubercular ridges or crusts. T. officinale: Synchytrium taraxaci
18a The inducer is situated inside the galls => 19
18b Spindle-shaped yellowish swellings bearing aecia. T. officinale: Puccinia dioicae
19a Galls locally confined, with tough, glabrous surface => 20
19b Galls without cavities, of different sizes and situations; spongy soft, yellowish-green, the surface ± undulately rugose; strongly curving the inflorescence stalk; also sometimes extending from the stem into the receptacle of the swollen and ± curved flower head. T. officinale: Ditylenchus dipsaci
20a Inflorescence stalk usually with many massive bulges over its complete length, spindle-shaped ± vitreous, yellow-green, which sometimes cause slight bending of the stem. T. officinale: Protomyces pachydermus
20b Base of inflorescence stalk slightly swollen over a length of several cm, close to the ground with several irregular humped protruding bulges, conspicuous when compared with unaffected shoots by their more compact structure. In the proliferated, more compact pith are 1‒2 (3) tunnelling larvae. T. officinale: Phytomyza wahlgreni
20c Localised tough-walled unilocular galls, 2–4 mm long, distinctly defined, pale green or also conspicuously reddened, often coalesced into much larger 25 mm long and 10 mm thick, ± tuberculate structures. Containing one white larva per chamber. T. officinale: Phanacis taraxaci
Laatste bewerking 30.iv.2020
Dichotomous table for gallers on Phragmites
1a On vegetative plant parts => 2
1b Ovary infected by smut fungus: Neovossia danubialis
1c In florets; a solitary pinkish larva replacing the ovary. Unidentified gall midge
2a On shoots, leaf-blades or -sheaths => 6
2b On lower internodes of the culm => 3
3a Culm distinctly or weakly swollen => 5
3b Galls inside the culms, which are not remarkably changed on the exterior => 4
4a Wall of the culm with single or many grain-like swellings, oval to spindle-shaped, rarely over 6 mm long, thin- and later tough-walled, unilocular; mostly protruding inside the culm, if heavily infected also protruding externally on the ± turgid culm. One white to orange-coloured larva per gall: Giraudiella inclusa
4b Rarely visible swelling on the clearly stunted culm. Larvae solitary in separate chambers in pith, which are sometimes present in large number per internode: Tetramesa phragmitis
5a Culm in the non-flowering unshortened upper part slightly swollen. Many orange-coloured larvae present in the dark or black pith. Infestation often inconspicuous: Lasioptera flexuosa
5b Several internodes of the culm, occasionally also the rhizomes, shortened and sometimes noticeably swollen beyond the normal diameter. Body of the gall sometimes constricted at the nodes; therefore reminiscent of slim concatenate spadixes of Typha. Covered for a long time by the black-brown sori, which remain closed until spores are released at about flowering time: Ustilago grandis
6a Galls in or on the shoot tips => 7
6b Leaf blades of the younger, already ± unfolding leaf blades rolled over their length and bleached: Hyalopterus pruni
7a The galls develop on the shoot tips as swellings of the culm => 9
7b The galls develop partially or completely from terminal leaves of the shoot => 8
8a Internodes compressed at the shoot tip; the adjacent youngest leaves swollen, transversely and longitudinally folded, ± twisted; the inwardly facing epidermal cells developed into club-shaped, brown, hairs in dry conditions. Usually the upper part gradually narrowed, heavily wrinkled, sometimes covered by normal leaf blades, gall breaks with its basal parts in ± buckled curves through the enveloping leaf sheaths: Steneotarsonemus phragmitidis
8b Leaves and the stunted, non-leafing shoot tips similarly deformed. Infected parts usually less swollen. Gall at its base often likewise curved and protruding. Club-shaped hairs absent. Between the swollen, dark coloured parenchyma are many dark orange-coloured gall midge larvae: Giraudiella inclusa
9a On the tips of main shoots => 10
9b Longitudinal growth of lateral shoots ± stunted, deformed to 15‒30 (50) cm long obliquely ascending slightly spindle-shaped swollen, tough-walled shoots. Leaf sheaths well developed, ± gaping, the closely converging leaf blades markedly shortened. In the dark brown to blackish coloured pith are many white to bright reddish-yellow gall midge larvae living in isolated chambers: Lasioptera arundinis
10a Gall usually less than 8 cm long and slim => 11
10b The characteristic “cigar” galls are up to 15 cm long and 1.5 cm wide. Terminal internodes markedly shortened and swollen; cross walls are missing in the older, initially still green galls which, from autumn onwards, turn brown and woody. Leaves converging, sheaths well developed, tight fitting, development of leaf blades variable, often considerably stuntedA fat, in mature condition 7‒10 mm long, cylindrical white-yellow maggot lives inside the tube-shaped chamber: Lipara lucens
11a Especially in the stem parts less conspicuously developed gall without chamber and no thickening of the stem. Wall hardly lignified. Sheaths spindle-like swollen; leaf blades usually normally developed, clearly separate from the gall. The larva lives between the leaf sheaths growing from the two terminal nodes, its position marked by a dark brown rotting channel: Lipara similis
11b Gall slender, c. 1.8 x diameter of normal shoot, central chamber not woody. The upper leaf is not normally developed but shortened and remains ± boat-shaped. Leaf sheaths broadened; leaf blades of the lower leaves normal, dropping off in autumn. Larva situated above growing point: Lipara rufitarsis and/or L. pullitarsis
Laatste bewerking 26.iv.2020
Dichotomous table for gallers on Papaver
1a On parts above ground => 2
1b Roots with nodular swellings. P. argemone, rhoeas: Meloidogyne hapla
1c Cyst -developing eelworm in hardly disfigured roots. Papaver sp.: Heterodera schachtii
2a On flowers and fruits => 6
2b On vegetative organs => 3
3a Malformations caused by animals => 4
3b Malformations caused by fungi. Leaves of often completely diseased and severely stunted young plants narrowed, pale and thick. Partially infected young leaves on usually expanded infestation area yellow-green, between veins bladder-like swollen, fleshy thickened, the margins rolled downwards and on underside covered with a dense, white-grey to pale violet down of conidiophores. Diseased flower- or capsule stalks, variously distorted due to stunting; buds and capsules crippled and disfigured. P. dubium, rhoeas, somniferum: Peronospora arborescens
3c Similar malformation, mainly on leaves. P. argemone: Peronospora argemones
4a Malformations caused by aphids and spittlebugs => 5
4b Midrib of rosette leaves stunted, especially at base, spongy thickened; leaf blades ± nested, curved; young axial parts basally greatly shortened or with local, ± distorted pale swellings. Papaver spp.: Ditylenchus dipsaci
4c Stem from the outside not disfigured; many rotund, thin-walled galls inside; “cryptocecidia”. Each gall containing a single larva. P. bracteatum, lasiothrix, pseudoorientale, somniferum: Iraella luteipes
4d Midge larvae developing in stems of P. nudicaule: Karshomyia caulicola
5a Complete plant disfigured; leaves rolled downwards, curled, ± discoloured. Papaver spp.: Aphis fabae
5b Leaf blade strongly deflected, curled and deep green close to the froth-covered nymph. P. orientale, rhoeas, somniferum: Philaenus spumarius
6a On or in fruit capsules => 7
6b Double flowers. P. alpinum: Unidentified gall mite
6c Flower buds transformed into a rosette of short leaves and bracts wrapping an irregular globular area with a plurilocular gall containing 2‒6 cells, flowers aborted. P. dubium, rhoeas: Iraella hispanica
7a Galls not or hardly visible from the outside => 8
7b Large parts or complete capsule strongly swollen and disfigured. Septa absent or reduced to short ridges. Tissue inside capsule soft, towards margin ± cracked with many tough-walled larval chambers. P. argemone, dubium, rhoeas, somniferum: Aylax papaveris
8a Tough walled, small, white galls located on the septa, up to 2 mm long, developing from seed primordia. Containing a single white larva. P. argemone, dubium, hybridum, rhoeas: Aylax minor
= Inquiline cynipid wasp: Parnips nigripes
8b Between strongly swollen septa of sometimes ± distorted capsules live many orange-red midge larvae. P. argemone, dubium, fugax, rhoeas, somniferum: Dasineura papaveris
Laatste bewerking 25.iv.2020
Dichotomous table for gallers on Vaccinium
1a Galls on parts above ground => 2
1b Roots with sometimes almost star-shaped swellings, 2–3 mm long, white on outside- and inside. Inducer unknown
2a Galls on leaves, on tips, also terminally on shoots or witches’ broom-like malformations => 4
2b Galls on axial parts of shoot => 3
3a Young stem parts locally broadened, with small, rimmed depressions, which harbour the causer under a pear-shaped white scale. V. myrtillus, vitis-idaea: Chionaspis salicis
3b Stem, usually over several internodes, swollen on all sides, up to 2–3 times the normal volume. Diseased parts rigidly erect, abnormally elongated; galls sometimes interrupted by normal parts, at first white or pink to reddish, later on cork-brown. Epidermis cells contain fruiting bodies. Lower leaves on galled shoots disfigured, usually dropping prematurely. V. corymbosum, membranaceum, vitis-idaea: Pucciniastrum goeppertianum
4a Malformation of several leaves or organs on tips or terminally on sometimes witches’ broom-like disfigured shoots => 9
4b Leaves, exceptionally also flowers, with ± expanded, localised galls => 5
5a Leaf blade with rolled margins or weak protrusions => 6
5b Smaller or larger parts of leaf blade or flowers often strongly swollen; on leaf upperside crimson-red or yellow, usually ± depressed; the arching on underside at maturity densely covered with dusty, chalk-white, basidia with 4 (‒6) spores. V. vitis-idaea: Exobasidium vaccinii
6a Roll of leaf margin => 7
6b Small depressions on lower surface of leaves. The upper part of the gall is usually red coloured and surrounded by a yellow patch. V. uliginosum: Contarinia sp.
7a Leaf margin rolled; on V. oxycoccos, uliginosum => 8
7b Roll of margin on V. myrtillus, vitis-idaea. Roll narrow, 1–1.5 mm broad, compact, often downwards, sometimes upwards, cartilaginously thickened; at first not, later on yellowish discoloured, margin ± concave. Containing a single larva: Dasineura myrtilli
8a On V. oxycoccos. Roll downwards, compact, slightly thickened and reddened. Containing several yellow-red larvae. Unidentified gall midge
8b On V. uliginosum. Leather-like thickened, yellowish or reddened downward roll. Containing a single yellow or reddish larva: Hygrodiplosis vaccinii
9a Leaves on shortened shoot tips keel-shaped, slightly thickened, uneven, imbricate; developing into a gall, sometimes ± blood-red, up to 8 mm long and 5 mm broad, in which the exterior leaf mostly encloses the inner ones containing a single red larva. V. myrtillus: Jaapiella vacciniorum
9b Malformations of larger expansion => 10
10a Malformations by fungi; at maturity densely covered by white fruiting bodies => 12
1b Malformations caused by animal parasites => 11
11a Leaf blades of several leaves reduced, ± undulately folded or wrinkled; margin and tip curved ± upwards. V. myrtillus, uliginosum: Phyllocoptes vaccinii
11b Several leaves on shoot tips slightly twisted; glossy green-yellow aphids occur on underside. V. vitis-idaea: Wahlgreniella vaccinii
12a Malformations without conspicuous thickening of stem => 13
12b Terminal part of stem or axis of inflorescence conspicuously succulent to varied extent. Leaves inserted on the galled part or flowers also variously strongly thickened. V. vitis-idaea: Exobasidium vaccinii
13a Stem usually not hypertrophied, in often large expansion and bearing several often vividly red or more yellowish coloured leaves. Leaf blades often larger, sometimes smaller than normal ones, less glabrous and glossy, weakly thickened, arched in many cases. Mycelium on underside. Malformations almost witches’ broom-like. Flowers usually atrophy on such shoots; sometimes all parts are moderately enlarged, but hardly thickened. On V. myrtillus, uliginosum, vitis-idaea => 14
13b Similar malformations on V. oxycoccos. The diseased parts slightly hypertrophied, distinguished from healthy parts by their erect growth. Leaves thickened and enlarged: Exobasidium oxycocci
13c Slightly disfigured shoots; first-year leaves sometimes enlarged, pale green or rarely becoming red. V. uliginosum: Exobasidium expansum
Laatste bewerking 24.iv.2020
Dichotomous table for gallers on Valeriana
1a On parts above ground => 2
1b Roots with nodular, club- or spindle-shaped slender swellings, a few mm long, which bear side roots. V. excelsa subsp. sambucifolia, officinalis: Meloidogyne hapla
2a On flowers or inflorescences => 10
2b On leaves and stems => 3
3a Malformations bearing sori => 9
3b Malformations lacking sori on outside => 4
4a Galls on leaves, sometimes encroaching onto stem parts => 5
4b Shoot axis stunted. Leaves variously deflected, curled, locally deep green. Infected inflorescences ± clustered, ball-like. The froth-covered nymph occurs also on single, similarly disfigured leaves. Valeriana spp.: Philaenus spumarius
4c Stem swollen. V. officinalis: Ditylenchus dipsaci
5a Leaves rolled inwards, frayed or curled => 6
5b Many multicellular warts, less than 1 mm long, at first golden-yellow, later on ± browned, on leaf blades, -stalks and basal stem parts. Sometimes coalescing, crust- or ridge-like, additionally disfiguring the infected parts. V. dioica, montana, officinalis: Synchytrium aureum
6a Leaf blades slightly rolled inwards => 8
6b Leaf blades otherwise ± severely disfigured => 7
7a Tips of leaves sometimes excessively deeply dentate or frayed, rolled upwards or twisted, discoloured, sometimes abnormally haired. V. dioica, montana, tripteris: Unidentified gall mite
7b Leaf tips converging and curled, inflated, twisted, thickened and discoloured. Containing single to several white jumping larvae. V. excelsa subsp. sambucifolia, montana, officinalis, tripteris: Contarinia crispans
8a Leaf blade loosely rolled. V. tripteris: Unidentified psyllid
8b Leaf blade loosely rolled inwards, black aphids on underside. Valeriana spp.: Aphis fabae
9a Distinct swellings, ± yellowish, sometimes curved, up to 15 (20) mm long, often yellowish margined on leaf veins, -stalks or stems, bearing irregularly or circularly arranged aecia, as well as spermogonia. Valeriana spp.: Uromyces valerianae
9b Aecia in coherent, expanded sori on slightly thickened, sometimes ± distorted, occasionally discoloured pads, which may, depending on condition of organ, measure up to 10 cm. The teliospores also soon develop in the same sori. II absent. Sori on leaf blades, -midrib and -stalks, on axial parts of shoot and inflorescence, also occurring on bracts and calyx. V. excelsa & subsp. sambucifolia, montana, officinalis, procurrens, tripteris: Puccinia commutata
10a Flowers leafy or greened (phyllanthy) => 11
10b Axial parts of inflorescence ± stunted. Flowers sometimes densely gathered together, unopened and infertile. Containing several, white to ivory jumping larvae. V. excelsa & subsp. sambucifolia, officinalis & subsp. collina: Contarinia valerianae
11a On V. dioica, montana, tripteris => 12
11b On V. officinalis. Axial parts of inflorescence shortened; flowers irregularly clustered, ball-like. Calyx hardly changed; inner flower parts variously leafy. V. doica, officinalis. Aceria macrotuberculata
12a On V. montana. Flowers disfigured, ± greened or double. Unidentified gall mite
12b Flowers leafy. All parts transformed into green, hairy small leaves. Often excessively branched. Bracts ± disfigured. Flowers double if weakly infected; calyx and corolla greened; stamens and ovaries corolla-like. V. dioica, tripteris: Unidentified gall mite
Laatste bewerking 30.iv.2020
Dichotomous table for gallers on Viburnum
1a On parts above ground => 3
1b On root collar or on roots => 2
2a On stem base gall-like, clumpy accumulation of stubby, succulent, swollen, ± branched and broadened shoots. “Leafy gall”. V. opulus: Rhodococcus fascians
2b Roots with nodular to spindle-shaped swellings. Viburnum spp.: Meloidogyne hapla
3a On flowers => 13
3b On axial parts of shoots, shoot tips or leaves => 4
4a On shoot tips and leaves => 6
4b On axial parts of shoots => 5
5a Pencil- to finger-thick twigs bear on several nodes globular to spindle-shaped swellings, up to 20 (33) mm thick, at first succulent, soon woody, slightly longitudinally grooved on their surface, which extends more than halfway around the axis. V. opulus: Agrobacterium tumefaciens
5b Thinner axial parts with rimmed depressions containing causer under pear-shaped scales up to 3 mm long. V. lantana, opulus: Chionaspis salicis
6a Malformations of indefinite shape, mainly on several terminal leaves => 9
6b Leaves with localised galls, ± constant in shape or with ± expanded pubescence => 7
7a Galls lenticular or spherical => 8
7b Underside of leaves with dense, abnormal pubescence on ± expanded rotund spots. Hairs ± stalked, star-shaped, slightly larger and more rigid than normal ones. V. lantana: Unidentified gall mite
7c Clusters of hairs causing depressions in vein axils. V. tinus: Unidentified gall mite
8a Pouch galls protruding on upperside, usually many, short-stalked, pinhead-shaped; sometimes ± reddened, covered with rigid hairs. With a strongly pubescent exit hole on underside. V. carlesii, lantana, rhytidophyllum: Eriophyes viburni
8b Leaf blades often with many parenchyma galls, up to 6 mm broad, rotund, flat on both sides often ± reddened on upperside, pale green on underside. Each containing a single orange-yellow larva. V. lantana, maculatum: Sackenomyia reaumurii
9a Malformations of many leaves on often conspicuously shortened shoot tips of younger or older bushes; caused by aphids => 10
9b Leaf blades of young plants or older bushes or basal shoots at infestation site deflected, especially over the tip; leaf blade curled and locally deep green. Viburnum spp.: Philaenus spumarius
10a Malformations on V. opulus and several cultivated species, rarely on V. lantana => 11
10b Malformations only on V. lantana. Leaf margin loosely rolled. Aphid olive-yellow to –green, with broad transverse brown-black bands: Aphis lantanae
11a Leaves strongly curved or curled => 12
11b Leaves usually slightly curled and slightly rolled inwards at margin. Galls only in spring. V. opulus and several cultivated species: Aphis fabae
12a Malformations inhabited throughout the year. V. opulus, lantana and many cultivated species. V. carlesii, cotinifolium, dilatatum, lantana, opulus, rhytidophyllum, tinus: Aphis viburni
12b Similar malformations, but only inhabited in spring. V. lantana, opulus: Ceruraphis eriophori
13a Flowers swollen, unopened, often partially reddened. Corolla thickened, slightly leathery. Stamens partially aborted. Ovary ± swollen. Containing yellow, jumping larvae. V. lantana, opulus: Contarinia lonicerearum
13b Similar flower galls with 2–3 white to sulphur-yellow jumping larvae. V. lantana, opulus, tinus: Contarinia viburnorum
Laatste bewerking 24.iv.2020
Dichotomous table for gallers on Vinca
1a On stems, buds or leaves => 2
1b Roots with nodular to slender spindle-shaped swellings. V. minor: Meloidogyne hapla
2a Malformations of leaves or shoot tips caused by animals => 5
2b Perennial mycelium disfigures complete shoots, which grow with elongated, thinner internodes rigidly erect. Leaves pale green, shortened and thickened; the younger ones curved upwards over their length, keel-shaped. Shoots non-flowering or rarely developing some disfigured flowers => 3
4a On V. herbacea. Infected shoots grow erect, not prostrate like healthy ones, and are etiolated. Leaves distinctly reduced, pale green on underside with many spermogonia and often in lines arranged uredinia and later on ± punctiform telia: Puccinia anatolica
4b Malformations on V. minor similar to fungi occurring on previously reported hosts, but distinguished by lacking uredinia: Puccinia cribrata
5a Malformations caused by aphids => 9
5b Other gall causers => 6
6a Leaf margins loosely rolled inwards or with kidney-shaped swellings. Leaves not conspicuously clustered => 8
6b Buds severely stunted with thickened leaves or top parts of shoots shortened with leaves more clustered => 7
7a Buds severely stunted terminally on end- or side shoots. Between thickened leaf blades of still unfolded buds are several reddish larvae. V. herbacea, major: Dasineura vincae
7b Terminal part of shoot ± shortened. Leaves erupting from buds, more clustered. Leaf blades pod-shaped, often rolled upwards to midrib; lighter, rough, ± bent and twisted. V. herbacea: Aceria liszkai
8a Leaf margin loosely rolled inwards. V. minor: Unidentified psyllid
8b Leaf margin with kidney-shaped swelling. ? V. minor: Inducer unknown
9a Young leaves slightly twisted. Aphid 1.5–2.3 mm long, pale yellow to greenish-yellow, with variable black marks, reminiscent of a horse shoe. V. difformis. major, minor: Aulacorthum circumflexum
9b Malformations may also be caused by Rhopalosiphoninus staphyleae
9c Young leaves severely disfigured, with many pale green or browned spots, resulting from stunting. V. minor: Aulacorthum solani
Laatste bewerking 24.iv.2020
Dichotomous table for gallers on Berberis
1a On above-ground parts => 2
1b Roots with nodular swellings. B. vulgaris, aquifolium: Meloidogyne hapla
2a Malformations on ± more expanded parts, bearing spores => 7
2b Galls caused by animals => 3
3a Galls on vegetative parts => 4
3b Fruits greatly enlarged; containing up to 4 non-jumping, pale green larvae. B. thunbergii: Unidentified gall midge
4a Malformations of leaves => 5
4b Stem with lateral, many-chambered swellings, crooked on surface, often red-brown. Containing several red larvae. B. vulgaris: Lasioptera berberina
5a Galls caused by insect inducers => 6
5b Galls caused by gall mites. Leaf blade reddish-brown with rusting. B. thunbergii, vulgaris: Phyllocoptes granulatus
6a Leaves on axillary buds, more rarely on shoot tips, rolled upwards, at first densely clustered, later on pushed apart; rolled part wrinkled or with small protuberances, cartilaginous, thickened; discoloured or ± dark red to violet on outside. Larvae at first translucent, later on white. B. vulgaris: Dasineura berberidis
6b Leaf blades on underside with lighter depressions, up to 3 mm long; with corresponding archings on upper side. Leaf margin bent downwards. B. vulgaris, x Mahoberberis neuberti: Trioza scottii
6c Leaves disfigured, ± distorted; more strongly infected shoots stunted. Aphid 2–2.5 mm long, yellow, also red or greenish. B. aquifolium, hispanica, thunbergii, vulgaris; x Mahoberberis neubertii: Liosomaphis berberidis
6d Shrivelled egg capsules, with several arranged in a half circle. “Procecidia” (oviposition scars, not true galls). B. vulgaris: Arge berberidis
7a Aecia on locally defined cushions => 8
7b Aecia on witches’ broom-like disfigured shoots. Berberis spp.: Puccinia arrhenatheri
8a Aecia cup-shaped, with deflected, frayed margin; on rotund or oval bulges on leaf underside, up to about 5 mm long, strongly arched, often orange-coloured to red, sometimes also on the green parts of inflorescences and flowers as well as on buds, young fruits and axial parts. B. vulgaris, aquifolum; Mahonia bealei: Puccinia graminis
8 Galls and aecia very similar to those of Puccinia graminis, distinguished only by microscopical characters; mainly occurring on young leaves. Wall of aeciospores of same thickness all around. Sori 2–8 mm across, at first greenish, later on brownish, bulging cushions on leaf underside; spermogonia on deep red discoloured leaf upper side. Occasionally also on leaf midrib, -stalks, or on young axial parts. Spermogonia usually dull orange. Berberis aquifolium, repens; Mahonia japonica: Cumminsiella mirabilissima
Laatste bewerking 24.iv.2020
Dichotomous table for gallers on Avenula
1a On inflorescences or flowers => 8
1b On culms, shoot tips or leaves => 2
2a On leaves or shoot tips => 4
2b On culms => 3
3a Upper internode of culm with one-sided, hard, reddish swelling about 10 mm long and 3 mm wide. Avenula pubescens: Tetramesa sp.
3b The diseased culms develop early, usually over their complete length, because of increased growth above all the basal internodes and have smut patches on their culms ± protruding from the leaf blades on all sides. Spores clustered with 1–2 (4) per ball, enveloped by a layer of many auxiliary cells. Avenula pubescens; Helictochloa versicolor: Urocystis avenastri
4a Malformations caused by animals => 5
4b The shortened, narrowed and often setose leaves on the often rigidly erect, soon stunted shoots with rows of often coalescing, later on erupting smut sori releasing black spores. Spores solitary. Avenula pubescens, Helictochloa pratensis: Ustilago scaura
5a Malformations on ± distinctly stunted shoot tips => 6
5b Leaf blade with less than 10 mm long, often purple, narrow cylindrical swelling. Helictochloa pratensis: Unidentified eelworm
6a Galls caused by larvae of insects; occurring inside => 7
6b Malformations caused by aphids occurring on the outside. The terminal leaf sheaths ± inflated and discoloured. Leaf blade variously twisted, curled or ± rolled inwards. Avenula pubescens, Helictochloa pratensis: Rhopalosiphum padi
7a Tuft-like accumulation of leaves on the upper internodes of the ± thickened shoot tip. Containing a single larva in pith. Avenula pubescens: Tetramesa sp.
7b Development of young shoots stunted while still close to the ground. Stems from their base onwards slightly swollen and excessively shortened towards the tip. The leaves close to one another, but not clustered into a tuft; their bases and sheaths often conspicuously reddened. Avenula pubescens, Helictochloa planiculmis: Chlorops pumilionis
8a Various malformations of spikelets, dependent on the reactive ability during infestation, often associated with leafiness and greening of the spikelets, eventually atrophying of all parts resulting in bleaching. Avenula pubescens, Helictochloa pratensis: Aceria tenuis and/or A. cornuta, Aculodes dubius
8b Ovaries disfigured often in many or all flowers of a panicle, soon destroyed and replaced with a black, dusty spore mass. Avenula pubescens: Ustilago avenae
Laatste bewerking 24.iv.2020
Dichotomous table for gallers on Aquilegia
1a On above-ground parts => 2
1b Roots with spindle-shaped to lenticular swellings. A. atrata, chrysantha, vulgaris; Meloidogyne hapla
2a On flowers => 7
2b On leaves => 3
3a Malformations caused by animals => 5
3b Malformations caused by fungi => 4
4a Expanded yellow, sometimes violet margined sori on the leaf underside bearing aecia; rotund on leaf blades, oblong-oval on major veins, rachis or stalk. Rust fungi with different host alternation developing similar galls; aecia in May, June:
a Aecia usually on distinctly swollen pads or ± curved bulges. Aquilegia spp.:
Puccinia recondita f. sp. agrostidis
b In similar aecia on A. vulgaris, only slightly cecidogenic: Puccinia actaeae-agropyri
c Usually causing stronger malformations: Puccinia actaeae-elymi
d In similar aecia but differentiated by smaller aeciospores, only known from Aquilegia: Puccinia scarlensis
e Leaflets with swollen blisters which rupture, exposing black powdery spore mass, whole leaf sometimes distorted. A. ottonis subsp. amaliae: Urocystis sorosporioides
4b Leaves or petioles with initially lead-grey translucent, later on rupturing bulges, up to 10 mm long. Containing black dusty spore balls. A. aurea, caerulea, vulgaris: Urocystis aquilegiae
5a Leaf blades arched, curled or curved; caused by aphids or spittlebugs => 6
5b Tips of basal leaves converging. Leaf blade etiolated; margin bent, partially curled to wart-like wrinkled, veins thickened. A. atrata: Unidentified gall mite
6a Parts of leaf blade of younger leaves clustered nest-like, their stalks and rachis shortened and bent. Leaflets curled close to the froth-covered nymph and dark green. Aquilegia spp.: Philaenus spumarius
6b Leaf blade slightly arched, locally often reddened. A. vulgaris: Longicaudus trirhodus
7a Malformations usually confined to single flowers on hardly stunted plants => 8
7b Development of plant often largely stunted, many parts disfigured. Flowers ± distorted; all parts reduced and leafy or, if weakly infected, only the inner parts disfigured. Aquilegia spp.: Cause unknown – ? virus
8a Flowers only slightly stunted and disfigured, not or hardly opened. ± greened. Containing several white to orange- red larvae. A. alpina, vulgaris: Macrolabis aquilegiae
8b Double flowers. A. vulgaris: Inducer unidentified – ? gall mite
Laatste bewerking 23.iv.2020
Dichotomous table for gallers on Apium
1a On parts above ground => 2
1b Roots with nodule-shaped swellings, occasionally clustered, ± curved. A. graveolens: Meloidogyne hapla
= Almost coral-like thickenings on roots of etiolated plants are caused by the ectoparasitically living, usually non-cecidogenic, needle eelworm Paralongidorus maximus. Also reported are the dagger eelworm Xiphinema sp.
2a Curl of leaves caused by aphids or cercopids => 7
2b Malformations caused by eelworms or fungi => 3
3a Bulge-like swellings caused by fungi with fructifications on surface => 6
3b Galls without fruiting bodies on surface => 4
4a Galls only a few mm long => 5
4b Mainly base of petioles spongy, swollen. Galls wrinkled. Leaf blades ± yellowing. Upper part of tubers sometimes with ± expanded protrusions, at first wart-like, then penetrating deeper, soon decaying, eelworm-rich infestation sites. A. graveolens: Ditylenchus dipsaci
5a Leaf blade with flat, pin head sized galls, at first white, then yellowish, eventually brown; also on petioles and stems, there occasionally coalescing into ± spindle-shaped bulges; sometimes even on rays of (partial) umbels as well as ovaries. A. nodiflorum: Buerenia inundata
5b In similar small pustules on leaves developing on A. nodiflorum, repens:
Entyloma helosciadii
5c Petiole and leaf veins, and stem with oblong-oval flat bulges, up to 3 mm long, pale green, later on browned. A. inundatum nodiflorum, repens: Physoderma vagans
5d Leaves with small hard pustules, less than 0.5 mm across. Apium spp.: Synchytrium aureum
6a Petiole, rachis, or leaf veins with spindle-shaped, distinctly pad-like arched, yellowish to brownish bulges, usually on underside. Aecia densely placed, cup-shaped, with distinctly protruding, frayed border; spermogonia countersunk. A. graveolens, nodiflorum: Uromyces lineolatus
6b Yellowish, slightly swollen bulging, rotund- to oblong-oval pads, occasionally on the venation, bearing spermogonia as well as aecia on underside. A. graveolens, prostratum: Puccinia apii
7a Large parts of leaf blade ± nest-like deflected; rachis shortened; leaflets close to the froth-covered nymph curled and intensely green. A. graveolens: Philaenus spumarius
7b Leaf blades slightly deflected; rachis shortened; causing complete leaf blade to become compact, ± depressed, with black aphids on underside. A. graveolens: Aphis fabae
Laatste bewerking 23.iv.2020
Dichotomous table for gallers on Anthemis
1a On above-ground part => 2
1b Roots with nodule-shaped slender humps, up to 4 mm, with beginnings of lateral roots. Cota tinctoria: Meloidogyne hapla
2a In capitula or fruits => 5
2b Plant partly or completely deformed => 3
3a Malformations by aphids or cercopids => 4
3b Plant bushy by inhibition of the internodes; mostly non-flowering; with pustule-shaped depressions over extensive areas, containing fruiting bodies. A. arvensis: Didymaria matricariae
3c Stem usually close to the ground with up to about 8 (12) mm long, broad spindle-shaped swelling, with a depressed break in the middle concealing a scale insect under a crooked shield. Cota tinctoria: Planchonia arabidis
4a Stems of young shoots locally stunted and curved; leaves closed, with their tips in different ways ± clump-like bent downwards. One froth-covered nymph. A. arvensis: Philaenus spumarius
4b Plant parts bunched together on the ± stunted shoot tips, downwards reflexed and curved; greenish aphids. A. arvensis: Brachycaudus helichrysi
5a Malformation of receptacle and of flower head => 6
5b Ovary or fruit swollen without or together with the lower flower parts. Also the bract may be involved in the gall formation. Containing a single yellow larva. A. arvensis, bornmuelleri, cotula, pseudocotula, rascheyana: Ozirhincus longicollis
5c Similar galls and biology. A. arvensis, bornmuellei, rascheyana, retusa; Cota tinctoria: Ozirhincus anthemidis
= O. longicollis and O. anthemidis differ by the length of the adult proboscis: in O. longicollis proboscis long, from base of labrum to tip of labella longer than height of eye; in O. anthemidis proboscis shorter than height of eye.
6a Receptacle thickened or occupied by independent ± separate galls => 7
6b Capitula deformed in different ways. Marginal flowers partially excessively elongate, ± misshapen and bent; often containing many oospores. Mycelium extended over large parts of flower head, changing into dirty violet-grey layers of branched conidia locally at the surface. A. arvensis, cotula, ruthenica; Cota austriaca: Peronospora radii
7a Complete receptacle swollen and hardened => 8
7b Between the flowers up to 3 mm long, cylindrical-conical achene-like galls, which differ from achenes however by their smooth compact wall. The galls are firmly inserted in the receptacle; the conical top becomes detached at maturity. Containing a single larva. A. arvensis, cotula; Cota austriaca; Cotula triumfettii: Rhopalomyia syngenesiae
8a Malformations caused by maggots of tephritid flies => 10
8b Malformations caused by beetle larvae => 9
10a Receptacle swollen, malformed, hardened. Larva without distinct head capsule, with black mandibles. A. arvensis, cotula: Eurasimona stigma
10b Similar galls. A. arvensis, cotula: Trupanea stellata
Laatste bewerking 22.iv.2020
Dichotomous table for gallers on Isatis
1a On parts above ground => 3
1b On roots => 2
1c Root collar with rotund, succulent, up to about 10 mm long swellings. Containing a single larva. I. tinctoria: Ceutorhynchus assimilis
2a Conspicuous, spindle-shaped to cylindrical swellings on main- and side roots. I. glauca, praecox, tinctoria: Plasmodiophora brassicae
2b Outside of roots little changed, temporarily bearing white to brown, poppy seed sized cysts. Giant cells develop inside. Isatis spp.: Heterodera schachtii
3a Malformations on shoot tips or on leaves, partially with conspicuous involvement of midrib; also on flowers => 7
3b Galls on shoot axis or petioles, without or with involvement of leaf blades => 4
4a Galls compact, caused by insects or fungi => 5
4b Galls pale green, spongy; confined to axial parts or only slightly encroaching into the leaf blade. I. tinctoria: Ditylenchus dipsaci
5a Rough-walled galls on stem, petiole or midrib, caused by beetle larvae => 6
5b Bulge-like, spindle-shaped, slight swellings on midrib, at first covered with glossy white, then mealy dusted sori. I. djurjudae, praecox, tinctoria: Albugo candida
5c The entire plant is disfigured. Upper side of the leaves locally bleached and galled; at the corresponding underside a greyish-white fungal bloom consisting of erect, distally strongly branched conidiophores. In the plant tissue locally oospores are formed, and particularly there galling occurs. I. tinctoria: Hyaloperonospora isatidis
6a Shoot axis stunted, with a long expanded swelling, containing several larvae. I. tinctoria: Ceutorhynchus sp.
6b Spindle-shaped, up to 12 mm long, also deep green inside gall; containing a single larva. I. praecox, tinctoria: Ceutorhynchus chalybaeus
7a Malformations on vegetative parts => 8
7b lower buds unopened, slightly swollen. Their peduncle slightly elongated and deflected, causing the galls to be ± hanging. Inside are several white to pale yellow midge larvae. Sometimes the larvae live in young flowering shoots in terminal, dense clusters of distinctly reduced buds between the organs. I. praecox, tinctoria: Contarinia nasturtii
8a Malformations of leaf blades => 10
8b Clustering of disfigured organs on ± stunted shoot tips => 9
9a Shoot axis distinctly shortened terminally, with dense tuft of ± stunted, almost sessile leaves, broadened at base, thickened and more pubescent. Containing several white to pale yellow larvae. I. praecox, tinctoria: Contarinia nasturtii
9b Shoot tips stunted, slightly thickened, organs inserted in dense clusters. Leaves stunted, curved and curled; flower buds reduced, partially ± exhibiting necrotic, greened organs. Infestation of isolated leaves results in the development of ± distinct, pale, ± reddish marbled swellings or folds. I. tinctoria, undulata: Brevicoryne brassicae
10a Leaf blade wrinkled and curled. I. tinctoria: Metaculus rapistri
10b On basal leaves the complete midrib is often ± curved, on larger leaves only the middle part over several cm is stunted and spongy, swollen, the leaf blades close to midrib are abnormally pubescent, bent upwards, strongly lacerated, on upper side bulge-like swollen. Containing several whitish to pale yellow larvae. I. praecox, tinctoria: Contarinia nasturtii
Laatste bewerking 22.iv.2020
Dichotomous table for gallers on Helianthemum
1a On inflorescences, flowers, capsules or on leaves => 4
1b On shoot tips or axial parts of shoot => 2
2a On shoot tips => 3
2b Shoot axis with ± expanded, sometimes bent, spindle-shaped to bulging swellings, in variable number, each containing the causer in a rimmed small groove. Helianthemum spp.: Planchonia arabidis
2c Swelling of 3 mm across. H. rosmarinifolium: Cistapion cyanescens
3a Tuft- or bud-like clustering of widened, thickened, often densely haired leaves. Containing several orange-yellow larvae. H. canum, nummularium & subsp. grandiflorum + obscurum: Dasineura helianthemi
3b Subglobose terminal gall, 4–5 mm across when young, composed of tightly imbricate, green or pale pink, leaves, shorter and a little wider than normal leaves. Mature gall up to 10 mm long, slender and consists of chestnut-brown, tough, curved scales. Gall one-chambered, rotund, containing a red larva. H. salicifolium: Unidentified gall midge
3c Cluster of whitish pubescent, short, thick leaves terminally on twig. H. croceum: Unidentified gall midge
3d Both terminal leaves of a shoot folded together, developing into a spindle-shaped gall, up to 6 mm long and 2 mm thick. H. canum: Unidentified gall midge
4a On inflorescences, flowers or capsules => 6
4b On leaves => 5
5a Expanded parts of leaves covered with long, 1-celled, browned hairs. H. nummularium: Unidentified gall mite
5b Leaves rolled inwards. Helianthemum spp.: Aphis helianthemi
6a Galls limited to flowers or capsules => 7
6b Complete inflorescence transformed into a dense mass of small, abnormally haired leaves, with ± excessive branching and leafiness. H. canum, nummularium & subsp. obscurum, oelandicum, stipulatum: Aceria rosalia
7a Malformations of flowers => 8
7b Minor swelling of ovary in flowers with stunted perianth. Containing a curved larva. H. nummularium & subsp. obscurum, ovatum: Phrissotrichum rugicolle
7c Minor malformations on capsules. H. nummularium & subsp. obscurum:
Helianthemapion aciculare
8a Flower buds thickened, unopened. H. nummularium: Unidentified gall midge
8b Flower buds slightly disfigured, but with strong abnormal pubescence. H. nummularium: Unidentified gall midge
Laatste bewerking 21.iv.2020
Dichotomous table for gallers on Gypsophila
1a On parts above ground => 3
1b On roots => 2
2a Spindle-shaped swellings on roots, up to 5 mm long and 2 (3) mm thick. G. elegans: Meloidogyne hapla
2b Conspicuous, proliferations on roots, root collar and stem base; 0.5–4.5 mm long; pale coloured, wrinkled-tuberculate at surface. Gypsophila spp.: Pantoea agglomerans pv. gypsophilae
3a On flowers => 9
3b On stems, shoot tips, or lateral leaf buds => 4
4a On shoot tips, buds or leaves => 5
4b Stem with expanded spindle-shaped swellings, the pith containing a caterpillar. G. fastigiata, paniculate: Caryocolum leucomelanella
5a On shoot tips or buds => 8
5b On leaves => 6
6a Malformations caused by animals => 7
6b Leaves sometimes with slightly swollen bulging, compact sori of dark-brown telia. G. elegans, muralis: Puccinia arenariae
7a Leaf blades at any point along length knee-like bent almost at right-angles. Breaking point close to midrib succulent, swollen, usually yellow-green, sometimes reddish. G. fastigiata: Planchonia arabidis
7b Leaves locally clustered, ± deflected and curled, partially deep green. Gypsophila spp.: Philaenus spumarius
8a Shoot tips or lateral buds stunted. Leaves transformed into a hemispherical to onion-shaped, often reddened gall. Occasionally enveloped by a spreading, basally strongly swollen ± fully developed pair of leaves; also may develop ± stunted leaf blades only at the base of galled leaves. Containing a single or several deep orange coloured larvae. G. fastigiata, repens: Bayeriola buhri
8b Leaves ± enlarged at the tip of vegetative shoots, curved inwards, ± converging, discoloured. G. repens: Unidentified aphid
9a Flower buds stunted, globularly inflated; containing dirty-yellow to brown-violet spores. Usually many to all flowers are disfigured on diseased plants. ? G. muralis: Sorosporium gypsophilae
9b Fungus develops in shortened and broadened anthers. Spores red-violet. G. repens: Microbotryum violaceum
Laatste bewerking 21.iv.2020
Dichotomous table for gallers on Geum
1a On leaves or flowers => 3
1b On shoot tips or stems => 2
2a Weak swelling of petiole or shoot axis below a node. G. urbanum: Unidentified weevil
2b Leaves at shoot tip tuft-like clustered; leaf blades ± folded upwards; main venation ± creased and thickened. Containing white larvae. G. aleppicum, rivale, urbanum: Contarinia gei
3a On flowers => 11
3b On leaves => 4
4a Leaf folds or – curls => 8
4b Leaves with abnormal pubescence, warts, pustule-shaped galls or irregular fleshy swellings => 5
5a Warts or pustules => 7
5b Leaves with fleshy galls or with felt-like pubescence => 6
6a Leaf blade, also its midrib, with fleshy swellings about 0.4–12 mm long, sometimes coalescing, irregular, pale- to yellow-green, on both sides of which an intercellular mycelium develops a cottony covering bearing asci. G. montanum: Taphrina potentillae
6b Leaf blade often severely disfigured, with at first whitish, soon brown-red erineum on underside, often along the veins; corresponding, at first pale green, then ± reddened upward archings on upperside, also erinea on both sides of leaf; erinea occasionally extending onto leaf midrib and petiole, shoot axis, flower peduncles and calyx leaves. Hairs cylindrical. G. aleppicum, molle, montanum, rivale, urbanum: Cecidophyes nudus
7a Small warts on leaf blade, midrib and petiole, up to 1 mm across, sometimes coalescing into expanded crusts, ± golden-yellow translucent. Geum spp.: Synchytrium aureum
7b Leaf blade with rotund pale coloured bordered pustules. G. rivale: ? gall midge
8a Leaf-blade curled, caused by aphids or spittlebugs => 10
8b Leaf blades of basal leaves or leaves on stem folded or rolled at margin, caused by gall midges or sawflies => 9
9a Leaflets, starting at midrib, variously folded upwards. Veins thickened; leaf blade ± twisted. Whitish larvae in folds on upper side. G. aleppicum, rivale, urbanum: Contarinia gei
9b Leaf blades, often of several leaflets as well as entire leaves, loosely clustered upwards, or remaining rolled inwards, beginning at margin, without substantial thickening. At first, hyaline-green caterpillars, bearing many forked setae, develop in the sometimes pale green roll and the wall of the roll is soon eaten away. Each roll containing a single, or several larvae. G. urbanum: Blennocampa sp.
10a Various malformations of leaves, caused by aphids. G. rivale, urbanum:
Macrosiphum gei
10b Often associated with strong downward deflection, ± bumpy, often dark-green curling of leaf. Geum spp.: Philaenus spumarius
11a Flowers contain gall midge larvae. Receptacle slightly swollen, calyx and corolla little changed; between the ± strongly reduced central flower parts are several red midge larvae. G. reptans: Geomyia alpina
11b Various greening of flowers. G. rivale, urbanum: ? gall mite
Laatste bewerking 20.iv.2020
Dichotomous table for gallers on Salvia
1a On parts above ground => 2
1b Roots with small whitish swellings, ± cylindrical-spindle-shaped. Salvia spp.: Meloidogyne hapla
1c Conspicuous tuberculate proliferations, mainly on root collar. Salvia spp.: Agrobacterium tumefaciens
2a On flowers or fruits => 9
2b On axial parts or leaves => 3
3a On leaf blades and -stalks, sometimes on stem parts => 4
3b Multilocular swelling of the stem, 10‒45 mm long and 8‒17 mm in diameter. The oval gall chambers are arranged at the outside, ± perpendicular to the wall. The young gall is yellowish green with a felty surface, in the end it is grey and lignified. S. fruticosa, syriaca: Hedickiana levantina
3c Stem distinctly swollen, sometimes distorted; with single or several oval, rimmed, groove-like depressions, in the cavities on underside containing the causer. S. x sylvestris, verticillata: Planchonia arabidis
4a Malformations on leaf blades, -stalks or stems caused by fungi => 7
4b Swellings, folds, curls or abnormal pubescence on leaves caused by animals => 5
5a Malformations caused by aphids => 6
5b Leaf blade with many pubescent ± reddened protrusions of variable size; dense, at first whitish, later on brownish erinea consisting of rigid, simple or branched hairs in the cavities on underside. Sometimes expanded erinea; also on leaf upperside; erineum sometimes encroaching into petiole and stem parts. Salvia spp.: Aceria salviae
6a Leaves folded, sometimes rolled at margin. S. officinalis: Brachycaudus cardui
6b Leaves pale-green spotted, swollen, bladder-like between the veins. S. nemorosa, officinalis, splendens: Aulacorthum solani
7a Swellings with aecia, sometimes associated with other spore forms => 8
7b Leaf blade with small, isolated pads, protruding on underside, sometimes slightly depressed on upperside, ± wart-shaped, bearing exclusively cinnamon- or chestnut-brown telia. S. aethiopis, dumetorum, limbata, nemorosa, nutans: Puccinia stipina
7c Upperside of the leaf with angular, eventually brown leaf spots. Underside with a thin, greyish purple to light brown fungal down of erect conidiophores that apically several times are dichotomously branching, each branch ending in a globular conidium. S. farinacea, officinalis, pratensis, purpurea, verticillata: Peronospora salviae-officinalis
8a Fungus host-specific. Sori often yellowish to reddish bordered, sometimes occurring on the leaf blades, there rotund, on underside ± bladder-like, arched; mainly oblong on veins and stalks, galls in that case variously distorted; with spermogonia and densely arranged, slightly protruding, irregularly opened, at margin lacerate aecia. Outer- and inner wall of peridium cells are thickened. S. judaica, x sylvestris, verticillata & subsp. amasiaca, virgata: Puccinia nigrescens
8b Only aecia with spermogonia on ± expanded, often curved, yellowish bulges on leaf veins and -stalks, occasionally on young axial parts, The cells of the peridium have thin inner walls. Salvia spp.: Puccinia stipina
9a Galls on flowers or flower parts => 10
9b Single or all four mericarps of a flower irregularly swollen, rotund, up to 5 mm long, multi-chambered, ± enveloped by calyx. Each chamber containing a single larva. Salvia spp.: Neaylax salviae
10a Flower galls caused by insects => 11
10b Malformations caused by fungi. Anthers already ± swollen in unopened flowers, globular and soon containing violet spores. Corolla with anthers dropping early. Development of fruit normal. S. pratensis: Microbotryum salviae
11a Galls caused by gall midges => 12
11b Gall caused by gall wasps, at the base of the flower head, rounded, monolocular, thin-walled, 4.0‒6.0 mm in diameter. 2‒3, sometimes more galls are developing. Salvia spp.: Neaylax salviae
12a Flowers remaining unopened. Calyx inflated and discoloured. Containing several flesh-red larvae. S. pratensis, x sylvestris, verticillata: Dasineura salviae
12b Swollen flower buds, contain orange coloured gall midge larvae. S. nemorosa: Asphondylia sp.
Laatste bewerking 20.iv.2020
Dichotomous table for gallers on Fragaria
1a On above-ground plant parts => 2
1b Nodular swellings on roots. Fragaria spp.: Meloidogyne hapla
1c Small solid swellings, often curved and twisted, at the tips of lateral roots; other parts of roots sometimes thickened. Slender and transparent adult eelworms, 1.5–12 mm long, feed on outside of root. Fragaria spp.: Longidorus sp. and/ or Xiphidinema sp.
2a Malformations are restricted to single or several plant parts or, if extending over larger parts are not “cauliflower”-shaped => 3
2b Complete plant ± severely disfigured; shoot stunted, thickened, curved; the many branchings ± fasciated or otherwise coalesced; leaves stunted, inflorescences disfigured; ‘cauliflower disease’ of cultivated strawberries. Fragaria spp.: Putatively combined infestation of: Rhodococcus fascians and/or Aphelenchoides fragariae
3a Flowers disfigured, calyx leaves elongated, corolla distinctly reduced and ± pale green. Flowers mainly sterile, ± clustered because of stunting of stalks. On cultivated strawberries, also on clover. Virus disease: “Flower greening of strawberry”
3b On stems, petioles or leaves => 4
4a Malformations mainly on leaf blade => 6
4b Galls on stems or petioles => 5
5a Oval to spindle-shaped or bulging swellings with single to several rimmed depressions, containing a scale insect. Fragaria spp.: Planchonia arabidis
5b Spongy swelling lacking a gall chamber, mainly at stem base or petiole. Fragaria spp.: Ditylenchus dipsaci
6a Leaf blade variously curved or crumpled => 8
6b Leaf blade with pouch galls or erinea => 7
7a Leaf blade on upperside with nodule-shaped pouch galls up to 1.5 mm long, red, ± pubescent; exit hole on underside. F. moschata, vesca, viridis: Fragariocoptes setiger
7b On leaf underside, spots with erinea of reddish discoloured multicellular, terminally blunt hairs. Fragaria spp.: Phytonemus pallidus subsp. fragariae
8a The inducer lives on the surface of the malformations => 9
8b Various curvings of often short-stalked leaves, mainly on stunted plants. Fragaria spp.: Aphelenchoides fragariae
9a The ± crumpled, locally deep-green leaf blades variously deflected and clustered. Containing a froth-covered nymph on underside. Fragaria spp.: Philaenus spumarius
9b Variously shaped malformations, often associated with curling, sometimes gall-like on yellow-green discoloured, ± vitreous, often severely stunted inner leaves. Caused by tarsonemid mites, living in the folds. Plants stunted. “Curling disease”. Fragaria spp.: Phytonemus pallidus
Laatste bewerking 19.iv.2020
Dichotomous table for gallers on Cydonia oblonga
1a On shoots, thinner twigs or leaves => 4
1b On thicker, woody stems => 2
2a Cancer-like malformation => 3
2b Thicker branches with club- or thick spindle-shaped swellings: Viscum album
3a Bark with ± expanded irregular, cracked proliferations, occupied by white woolly aphids: Eriosoma lanigerum
3b Rotund or flattened oval proliferations on basal stem parts, soon lignified, surface cork-like and granulated. Bacterial cancer: Agrobacterium tumefaciens
4a On leaves and shoots => 5
4b Bark of thin twigs with small nodules, with coarse surfaces: Acalitus phloeocoptes
5a Several leaves at shoot tips irregularly disfigured => 10
5b Leaves with locally defined galls => 6
6a Galls bulge-like or slightly bladder-like, soon covered with fungal sori => 7
6b Leaf blade with many rotund pocks, weakly protruding on both sides; these with narrow exit on underside: Eriophyes pyri
7a Galls bulge-shaped, yellowish, often on leaf veins, occasionally on young stems; cylindrical, tube-shaped, with sori which soon lacerate and rip open from apex downwards => 8
7b Leaf blade often with several weak bladder-like swellings, which display a white-grey cover at maturity consisting of many asci: Taphrina bullata
8a Lateral walls of peridium cells with obliquely or transversely running ridges => 9
8b Lateral walls of peridium cells with rotund tubercles: Gymnosporangium clavariiforme
9a Sori on leaf underside usually only weakly arched. Peridium protruding about 2 mm, later on frayed to its base, its cells 18–24 µm across. Aeciospores 19–26 x 19–22 µm: Gymnosporangium confusum
9b Sori on leaf underside usually distinctly arched. Peridium protruding up to 3 mm, later on frayed to its base, its cells 31–35 µm across; aecia 30–39 x 25–30 µm: Gymnosporangium tremelloides
10a Leaves strongly curled, clumped at the ± stunted shoot tips. Caused by aphids => 11
10b Leaf margin deflected downwards: Cacopsylla mali
10c Several terminal leaves on shoots stunted, disfigured, their margins ± bent upwards, slightly thickened and often completely covered by a sometimes cotton wool-like, white mycelium: Podosphaera leucotricha
11a Leaves in spring ± twisted along the midrib, more or less tightly rolled downwards, sometimes developing loose clusters at the shoot tips. Aphid green, with short, thick green siphunculi: Rhopalosiphum oxyacanthae
11b Similar malformations; often clusters more compact. Leaves usually also deflected over the tip. Aphid with rather long black siphunculi: Aphis pomi
11c Leaves are curled and yellowed. Aphids with red body fluids: Dysaphis pyri
Laatste bewerking 19.iv.2020
Dichotomous table for gallers on Arrhenatherum
1a On parts above ground => 2
1b Roots with spindle-shaped, half-screw-shaped bent swellings a few mm long; tissue with cavities. A. elatius: Subanguina radicicola
1c Similar, but compact, malformations sometimes on sagging root tips. A. elatius: Meloidogyne hapla
1d Roots of A. elatius may also become infected with Heterodera avenae
2a Malformations only on inflorescences or flowers => 6
2b On vegetative parts => 3
3a Leaves with long, parallel stripes caused by rusts or smuts => 5
3b Malformations of shoots caused by animal parasites => 4
3c Stems within the leaf sheaths, sometimes also the outside of the sheaths, covered by a dark brown layer of spores. A. elatius: Tranzscheliella hypodytes
4a Shoot conspicuously shortened, swollen at base. Stem only weakly developed, often not protruding from the sheath. Inflorescence with strongly etiolated spikes, sometimes also ± bleached. Contains many eelworms. A. elatius: Ditylenchus dipsaci
4b Shoot axis stunted; panicle stunted, bleached; contains a fly maggot. A. elatius: Unidentified Chloropidae
4c Longitudinally arranged, about 10 (12) mm long saddle-shaped, terminally rimmed depressions, which occur with several under the slightly swollen leaf sheaths above the nodes. Contain blood red midge larvae. A. elatius: Haplodiplosis marginata
4d Lateral swelling of stem, just above the ground, 10–12 mm long and 5–6 mm broad; large chamber contains a single larva. A. elatius: Tetramesa sp.
4e Black aphids under crumpled leaves. A. elatius: Melanaphis pyraria
4f Leaf sheaths of the upper part of stem ± bladder-like swollen; inside are many yellow- to brownish-green aphids, up to about 2 mm long. A. elatius: Laingia psammae
6a Inflorescences disfigured by smut fungi => 7
6b Panicle stunted, axial parts wriggled, spikes disfigured, clustered. A. elatius: Unidentified eelworm
6c Inflorescence contains yellow midge larvae. A. elatius: Contarinia arrhenatheri
7a Ovaries and flower peduncle, sometimes also the spikelets, swollen, and soon filled with masses of agglutinated spores. Often all panicles and flowers of a plant with smut, exceptionally only with some apical flowers remaining normal. Unfolding panicles not spreading; spores dispersing at once. A. elatius: Ustilago hordei
7b Malformations similar in all parts; spore masses hardened however, spores not dispersing immediately. A. elatius: Ustilago avenae
Laatste bewerking 18.iv.2020
Dichotomous table for gallers on Phalaris
1a Malformations on or in inflorescence, flowers or fruits => 11
1b Malformations of vegetative parts => 2
2a On leaves and culms => 3
2b Roots with half screw-like or crooked swellings. Phalaroides arundinacea: Subanguina radicicola
3a Complete plant disfigured, or malformations restricted to shoot tips or leaves => 7
3b Galls on culm => 4
4a Larvae between culm and leaf sheath => 5
4b Culm weakly swollen at upper internodes. Larva inside the stem. Phalaroides arundinacea: Tetramesa sp.
5a Midge larvae, lacking black mouth parts => 6
5b Larvae with black mouth parts, usually with several larvae inside the slightly swollen internode at base of an occasionally severely stunted and ± bleached inflorescence. Phalaroides arundinacea: Oscinella trochanterata
6a Culm above the node, underneath the leaf sheath, with several oblong-oval, flat, slightly rimmed depressions, each containing a single orange-yellow larva. Phalaroides arundinacea: Lasioptera calamagrostidis
6b Culm above the node with strong, sometimes almost saddle-like rimmed depressions. Larvae white to golden-yellow. Phalaroides arundinacea: Mayetiola phalaris
7a Complete plant severely stunted or apical leaves distinctly gathered together => 9
7b Malformations of leaf blades and -sheaths => 8
8a Aphid gall. Leaf sheath inflated, ± discoloured, leaf blade twisted, rolled. P. canariensis; Phalaroides arundinacea: Rhopalosiphum padi
8b With similar damage. P. canariensis: Sitobion avenae
8c Long parallel stripes caused by smut, especially on the upper leaves of the ± shortened shoots. Sori also on leaf sheaths, with dusting of blackish olive-brown spores. Panicles reduced, often remaining in sheaths. Phalaroides arundinacea: Ustilago echinata
8d In addition, same host, may occur the rare fungus: Physoderma graminis
8e Leaves curled and wrinkled; culms often severely distorted. Phalaroides arundinacea: Ustilago serpens
9a Malformations without conspicuous accumulation of apical leaves => 10
9b Plant severely stunted. Leaves terminally accumulated. Upper culm containing a single whitish larva. Phalaroides arundinacea: Tetramesa sp.
10a Young shoots often severely stunted in longitudinal growth; swollen at base sometimes slender onion-like. Developing shoots ± strongly shortened, often with many ± distinctly rimmed depressions above the nodes; shoots that continue to grow mostly bleaching. Often with large numbers of larvae per shoot. Phalaroides arundinacea: Mayetiola phalaris
10b Mites are vagrants at the upperside of the leaves and in the leaf sheaths. At higher densities the leaves may become discoloured and rolled. Phalaroides arundinacea: Acaralox arundinaceus
11a Malformations mainly of ovaries, fruits => 12
11b Inflorescence disfigured; flowers stunted, variously disfigured or bleached. Phalaroides arundinacea: Aceria tenuis
12a Ovaries slightly swollen, filled with brown spore masses. Phalaroides arundinacea: Tilletia menieri
12b Spikelets disfigured, ovaries enlarged, ± bottle-shaped. Often found associated with the fungus Dilophospora alopecuri. Phalaroides arundinacea: Anguina agrostis
12c Orange coloured midge larvae feed solitarily on developing ovaries. P. minor; Phalaroides arundinacea: Sitodiplosis phalaridis
12d Yellow gall midge larvae prevent the formation of seeds. Phalaroides arundinacea: Coniophora graminicola
Laatste bewerking 18.iv.2020
Dichotomous table for gallers on Onobrychis
1a On parts above ground => 3
1b On roots => 2
2a Nodular swellings of the root. O. viciifolia: Meloidogyne arenaria
2b Cylindrical nodules, up to 8 mm long, apically usually flattened or partitioned, which are laterally inserted into main- or secondary roots. O. viciifolia:
Rhizobium leguminosarum
3a On vegetative organs => 5
3b Malformations of flowers or immature fruits => 4
4a Ovaries of young flowers swollen. Perianth shortened. Corolla ± spreading; calyx conspicuously widened and especially bulging on one side. Containing a curved larva. O. viciifolia: Holotrichapion pisi
4b Flowers swollen, unopened. Larvae gregarious, lemon-yellow, jumping. O. arenaria, montana, viciifolia: Contarinia onobrychidis
4c In flower galls of Onobrychis sp. also non-jumping larvae of Dasineura floralis
5a Galls on single or many leaflets => 9
5b Galls on stem, petiole or midrib => 6
6a The inducers live inside the galls => 7
6b Petioles or midrib with single spindle-shaped swelling, also several broad swellings. Infestation strongly widened in the middle, bent, with a rimmed depression containing the inducer. The galls often develop gregariously on stems, with curved bulges containing several depressions. O. arenaria: Planchonia arabidis
7a Galls with tough wall => 8
7b Spongy, pale green, ± wrinkled swellings of variable expansion on stems and leaf axis of young plants. O. viciifolia: Ditylenchus dipsaci
8a Shoot axis with compact, multi-chambered swelling, up to 30 mm long. Larval chambers in several rows, each chamber containing a single white larva. O. arenaria, viciifolia: Aylax onobrychidis
8b About 5–8 mm long, spindle-shaped swellings in shortened inflorescence axis, often hidden by the clustered flowers. Galls each containing a single larva. O. arenaria, montana, viciifolia: Hemitrichapion reflexum
9a Leaf galls caused by gall midges => 10
9b Galls contain mites. Leaflets folded, irregularly bent, not fleshly thickened. Malformation usually on all leaflets of many leaves. O. arenaria, montana, viciifolia: Aculus longifilis
10a Leaflets folded together upwards, pod-like, fleshy thickened. On young leaves usually all, on older, often only several leaflets infected. Larvae gregarious, yellow-white. O. aequidentata, montana, viciifolia: Bremiola onobrychidis
10b Leaf galls. Onobrychis sp.: Janetiella foliicola
Laatste bewerking 17.iv.2020
Dichotomous table for gallers on Moehringia
1a On parts above ground => 2
1b Root with lentil-size swellings. M. trinervia: Meloidogyne hapla
2a On inflorescences or flowers => 11
2b On vegetative parts => 3
3a Several leaves with nearly similar malformations at shoot tips or all over the plant => 5
3b Locally restricted galls on leaves or stems => 4
4a Many yellow translucent multi-cellular warts, less than 1 mm long, on basal leaves and stem parts. M. trinervia: Synchytrium aureum
4b Rotund, sometimes depressed on upperside, yellowish to brown-yellow, on underside, pad-like swellings on leaves, or, elongate in direction of organ development, sometimes distorted bulges on axial parts up to 6 mm long. M. diversifolia, muscosa, tenuifolia, trinervia: Puccinia arenariae
5a Animal causers => 7
5b Caused by fungi fruiting at surface => 6
6a Systemically infected shoots longer and lanky; rigidly erect; leaves often longer stalked; small, pale, sometimes deflected at margin, with a dirty-white to grey down of branched conidiophores on underside. M. ciliata, trinervia: Peronospora arenariae
6b Similar malformations, usually on many shoots of a plant; on all green parts, especially on leaf underside, with many loosely arranged yellow sori. M. trinervia: Melampsorella caryophyllacearum
7a Caused by aphids or spittlebugs => 9
7b Caused by gall mites => 8
8a Leaves clustered at main- and side shoots, disfigured; flowers greened or double, also developing further. M. ciliata, lateriflora: Aceria moehringiae
8b Leaves wrinkled, clustered ball-like at shoot tip; development stunted; development of flowers suppressed; normal flowers exceptional. M. trinervia: Cause unknown – ? gall mite
9a Caused by aphids => 10
9b Shoot axis stunted, with local, sometimes almost facultative, nest-like clustered, deflected, ± curled, partially deep green leaves. M. trinervia: Philaenus spumarius
10a Leaves pod-like folded upwards, violet-marbled, inside weakly pubescent. M. trinervia: Brachycolus stellariae
10b Leaves terminally accumulated, reduced, sometimes discoloured, undulate curled, bent upwards, also deflected, sometimes slightly more pubescent. Aphid reddish to dark brown. M. trinervia: Myzus certus
11a Often largely leafy flowers associated with excessive branching. M. ciliata, lateriflora: Aceria moehringiae
11b In outwardly normal flowers the anthers are stunted, swollen and soon filled with a dusty violet spore mass. M. lateriflora: Microbotryum violaceum
Laatste bewerking 17.iv.2020
Dichotomous table for gallers on Echium
1a On inflorescences, flowers or fruits => 6
1b On vegetative parts => 2
2a On shoot tips, lateral buds, stems or leaves => 3
2b Complete plant stunted, leaves clustered and like flowers ± etiolated. E. vulgare: Brachycaudus helichrysi
3a On leaves, buds or stems => 4
3b Shoot tip stunted close to ground, transformed into an oblong-egg-shaped blotch with large central chamber, not enclosed by unfolding leaves. E. italicum, vulgare: Cynaeda dentalis
3c Gall on root head. E. vulgare: Pachycerus segnis
4a On leaves or buds => 5
4b Stem locally stunted and swollen, with several rimmed depressions containing a nymph. E. vulgare: Planchonia arabidis
5a Lateral buds transformed into an unopened egg-shaped gall, not dropping in autumn. Contains a single yellow larva. E. arenarium, vulgare: Asphondylia echii
5b Leaf blade with conspicuous, rotund, yellow or reddish pads, ± depressed on upper side, arched on underside or similar, elongated spindle-shaped bulges on venation. E. plantagineum, vulgare: Puccinia recondita f. sp. echii-agropyrina
6a On inflorescences, flowers => 7
6b One of the mericarps enlarged; the remaining ones aborted. Containing a single larva. E. vulgare: ? gall midge, ? gall wasp
7a Expanded parts of inflorescence disfigured => 9
7b Malformations of single or several flowers => 8
8a Corolla unopened, not or hardly surpassing calyx teeth; lower half swollen, thickened, white; upper half acuminate, thickened and reddish. Stamens and ovary thickened. Larvae glossy, lemon-yellow, jumping. E. vulgare: Contarinia echii
8b Flower swollen, unopened, gall rotund-oval. Stamens and pistil aborted. Inner wall lined with mycelium. Containing a single larva. E. arenarium, vulgare: Asphondylia echii
9a Many flowers disfigured, their parts variously leafy, abnormally pubescent. E. vulgare: Aceria echii
9b Inflorescences shortened. Flowers distorted. E. vulgare: Dictyla echii
9b Axis of inflorescence stunted and clustering of flowers of E. vulgare caused by froth-covered nymphs of Philaenus spumarius
Laatste bewerking 16.iv.2020
Dichotomous table for gallers on Aegopodium
1a On inflorescences, flowers or fruits => 9
1b On stems and leaves => 2
2a Leaf blades folded, curled, rolled inwards or with flat, ± bumpy swellings => 5
2b Leaves or stems with wart- to bulge-shaped galls => 3
3a Bulges over 1 mm long => 4
3b Galls wart-shaped, multi-cellular, less than 1 mm long, yellowish translucent; usually many on the underside of leaf blades, on petioles and basal stem parts; sometimes ridge- or crust-shaped coalescing: Synchytrium aureum
3c In similar galls: Physoderma pulposum
4a Spindle-shaped, compact, vitreous, pale green, later on ± browned bulges, often many on petioles, leaf veins and stems. Spores inside close to vascular bundle: Protomyces macrosporus
4b Leaves especially on underside, particularly on veins and stalks, with thickened, at first yellowish pads or bulges, on which develop 2-celled telia in black-brown sori, soon coalescing: Puccinia aegopodii
5a Leaf blades folded or flat to ± swollen, bulge-shaped => 7
5b Leaf blades rolled inwards or curled, caused by aphids or cercopids => 6
6a Leaf blades strongly converged downwards, almost claw-like; conspicuously curled and deeper green, especially close to the froth-covered nymph. Infected inflorescences stunted, compact: Philaenus spumarius
6b Tips of leaves usually transversely ± narrow to claw-like deflected downwards, irregularly shaped at surface on upper side by smaller or larger, often yellowish discoloured proliferations. Black aphids on underside: Aphis podagrariae
6c Aphid straw-pale to greenish: Aulacorthum aegopodii
7a Leaf blades with expanded swellings => 8
7b Tips of developing leaves folded upwards; ± curled and clumped. Main- and lower parts of lateral veins thickened. White larvae between folds: Macrolabis podagrariae
8a Often several upward protrusions of the leaf blade up to 6 mm long, hardly discoloured, sometimes violet marbled; corresponding depressions on opposite side; each groove contains an egg or larva: Trioza flavipennis
8b Leaves on underside with expanded white, loose covers of branched conidiophores. Infestation sites on upper side discoloured yellow-green, fast growing leaves sometimes slightly arched: Plasmopara crustosa
9a Galls only on flowers or fruits => 11
9b Umbel largely disfigured => 10
10a Development of umbel stunted, partial umbels accumulated because of shortened stalks. Flowers ± greened to leafy, often discoloured reddish: Unidentified gall mite
10b Partial umbels disfigured, clustered, stalks shortened, bearing green aphids: Cavariella aegopodii
11a lowers swollen, globular, not opening. Containing a single larva: Unidentified gall midge
11b Fruit distinctly swollen, bladder-like, protruding above the partial umbel. Containing an orange-red larva: Kiefferia pericarpiicola
Laatste bewerking 16.iv.2020
Dichotomous table for gallers on Aconitum
1a On vegetative plant parts => 2
1b Flowers not opening, conspicuously swollen, ± rotund, yellowish-, then bluish-green. Containing several whitish larvae. A. lycoctonum & subsp. vulparia, napellus, variegatum: Contarinia aconitifloris
2a Malformations ± bulging, caused by smut- and rust fungi => 7
2b Malformations caused by animal inducers => 3
3a Malformations caused by aphids or spittlebugs => 4
3b Stem just below the still undeveloped inflorescence ± spindle-shaped, or irregularly barrel-shaped, swollen over a length of 20–35 mm. The increasingly developed, also outside the gall irregularly eaten, pith contains a single or several larvae. A. lycoctonum subsp. vulparia, napellus subsp. lusitanicum: Ranunculiphilus lycoctoni
4a Malformations caused by aphids => 5
4b Large parts of leaf blade strongly deflected, strongly curled, especially close to the froth-covered nymph; dark green. Aconitum spp.: Philaenus spumarius
5a Leaves ± distinctly deflected. Aphids 3–4 mm long => 6
5b Shoot axis stunted. Leaves or flowers apically clustered, ± bent or disfigured. A. x cammarum, lycoctonum & subsp. vulparia, napellus, plicatum, variegatum:
Brachycaudus napelli
6a On A. lycoctonum & ssp. vulparia. Leaves broad and curved downwards, bell-like yellowish spotted: Delphiniobium lycoctoni
6b On blue-flowering species. Leaves only slightly rolled downwards and bent. Aconitum spp.: Delphiniobium junackianum
7a Malformations contain sori of rust fungi => 8
7b Stem, petioles or often leaf undersides often with curved bulges caused by smuts; initially closed, lead-grey translucent; rupturing later on and then with black dusting. Aconitum spp.: Urocystis irregularis
8a Bulges with aecia, accompanied by pycnidia. Fungus host-alternating => 10
8b Swellings with aecia, with or without pycnidia. Fungus not host-alternating => 9
9a Aecia predominantly in larger groups on swellings of sometimes curved leaf veins, -stalks and stems. Peridium dentate at margin, rather large. A. lycoctonum, vulparia: Uromyces dactylidis
9b Aecia in rotund-oval, ± arched sori usually on underside of leaf blades, broad disc-like, with deflected, soon withering and therefore rarely well-developed margin. Spermogonia on both leaf sides. A. lycoctonum & sspp. septentrionale + vulparia, orientale: Uromyces lycoctoni
10a Aecia on Aconitum spp. Underside of leaves with large, rotund, yellow-brown pads; leaf veins, -stalks or stems with distinctly bent or curved bulges, up to 30–40 mm long. Puccinia actaeae-elymi
10b Malformations and aecia like those of Puccinia actaeae-elymi; only occurring on blue-flowering species. A. x cammarum, degenii, napellus, tauricum, variegatum: Puccinia aconiti-rubrae
10c Aecia similar, morphologically not positively distinguishable from previous rust; predominantly on underside of leaf blade in usually rotund, sometimes slightly swollen, discoloured sori. A. x cammarum, lycoctonum & ssp. vulparia, napellus, tauricum, variegatum: Puccinia actaeae-agropyri
Laatste bewerking 17.iv.2020
Dichotomous table for gallers on Knautia
1a On inflorescences or flowers => 10
1b On vegetative parts => 2
2a Locally restricted malformations => 3
2b Complete plants ± stunted, organs variously disfigured. K. arvensis, dinarica, dipsacifolia, drymeia, longifolia: Aphis confusa
3a Malformations terminally on main- and side shoots or on leaves Malformations terminally on main- and side shoots or on leaves => 5
3b Galls only on axial parts of shoot => 4
4a Shoot axis often thickened below inflorescence and densely haired. K. arvensis: Ditylenchus dipsaci
4b Usually basal part of stem with conspicuous, spindle-shaped or irregularly bulging and ± buckled swellings, with single or several rimmed depressions; containing the causative froth-covered nymph under a bulging scale. K. arvensis:
Planchonia arabidis
4c Gall-like malformations on shoots of K. longifolia: unknown galler
5a Galls on leaves => 8
5b Galls terminally on shoots => 6
6a Galls restricted to shoot tips => 7
6b Variously shortened internodes on shoot tips, often predominantly one-sided, causing the leaves to cluster on ± curved stem; leaf blades stunted, ± deflected and curled, deep green close to the froth-covered nymph. K. arvensis, drymeia: Philaenus spumarius
7a Terminal leaves folded together, haired. Containing several white larvae. K. arvensis, dipsacifolia, drymeia, transalpine: Jaapiella knautiae
7b Terminal pair of leaves ± unfolding, completely thickened or only at base, folded together upwards, pouch-like; densely pubescent with rigid hairs. Containing a single yellow midge larva. K. arvensis, collina, drymeia: Unidentified gall midge
8a Galls only in leaf blade of basal leaves => 9
8b Petiole and midrib with pale yellow-green, spongy swellings, variously encroaching onto ± disfigured leaf blade. K. arvensis: Ditylenchus dipsaci
9a Very weak protrusions on underside in vein axils, hardly visible on upper side. K. drymeia, longifolia: Trioza munda
9b Up to 5 mm long, yellow, slightly protruding, often many pustules on leaf blades. Containing a single lemon-yellow larva. K. arvensis: Unidentified gall midge
10a Malformations caused by fungi => 12
10b Malformations caused by animals => 11
11a Malformations of flowers caused by jumping, whitish- to orange-yellow midge larvae. K. arvensis, drymeia: Contarinia dipsacearum
11b Capitula ± disfigured and weakly swollen. Containing a single caterpillar. K. arvensis: Stenoptilia bipunctidactyla
12a nfected flowers often of different colour, partially strange-looking. Several petals enlarged and disfigured; number enlarged by ± largely transformed stamens. anthers and ovaries mostly aborted. K. arvensis, dipsacifolia, drymeia, kitaibelii: Peronospora violacea
12b Diseased capitula almost half-globular. Involucral bracts normal; young flowers unopened for a relatively long time, often distinguished by early discolouration of all capitula of diseased plants. K. arvensis, dipsacifolia, drymeia, longifolia, pancicii: Microbotryum scabiosae
12c The anthers are transformed into a purplish-brown powdery mass of spores. K. arvensis, dipsacifolia: Microbotryum flosculorum
Laatste bewerking 14.iv.2020
Dichotomous table for gallers on Syphytum
1a On flowers or fruits => 9
1b On leaves, sometimes on stems => 2
2a Malformations caused by animals living on surface of host => 7
2b Malformations caused by fungi, fruiting inside or on surface of host => 3
3a Malformations conspicuous, bearing yellowish sori => 6
3b Galls small, up to 1.5 mm across. Spores originate inside nutritive cells => 4
4a Galls on leaf blades => 5
4b Galls only on hairs of leaves and stem. Hairs distinctly shortened and swollen, often with short, immediately narrowed, acutely bent tip. Inside are single or several rotund summer- or perennial sporangia up to about 50 µm large. S. officinale: Synchytrium trichophilum
5a Leaves with several wart-shaped protruding, small, multi-cellular galls, which develop in a centrally situated strongly enlarged nutritive cell yellow perennial sori. S. officinale: Synchytrium jaapianum
5b Expanded parts of leaf blade with many, densely arranged, but usually solitary, rotund to oblong-oval reddish- to dark brown, flat bulges. S. officinale: Physoderma speciosum
6a Tubercular bulges rotund on underside of leaf blade, on main veins, petioles and stems oblong-oval spindle-shaped, up to 15 (25) mm long, orange-coloured ± reticulate. Symphytum spp.: Puccinia recondita
6b Diseased plants or leaves lanky, paler. Large parts of leaf blade bearing small reddish- to brownish-yellow uredinia on underside. Symphytum spp.: Melampsorella symphyti
7a Malformations caused by aphids, spittlebugs or thrips => 8
7b Leaf blade curled, yellowish discoloured. Many white larvae on underside. S. asperum, officinale: Dasineura foliumcrispans
8a Leaf blade arched deflected, ± converging and curled. Symphytum spp.: Philaenus spumarius
8b Leaf blade rolled upwards, ± bent, sickle-shaped. S. cordatum, officinale: Aphis symphyti
9a On inflorescences or fruits => 10
9b On fruits. Development of several mericarps stunted, the remainder enlarged and white pubescent. Corolla disfigured, only opened a little and remaining unopened. Fruit containing several white larvae. S. officinale: Unidentified gall midge
10a Malformations of single or several flowers without conspicuous stunting of inflorescence => 11
10b Malformation and stunting of inflorescence as well as neighbouring leaves. Flowers distorted and disfigured; leaves rolled and curled. S. officinale: Dictyla humuli
11a lowers unopened, variously greatly swollen, especially base discoloured. Calyx sometimes with white-felt-like pubescence. Corolla distorted. Stamens and ovaries shortened and thickened. Often many white to yellowish, non-jumping larvae inside flowers. S. asperum, officinale: Dasineura symphyti
11b Flowers unopened, only slightly swollen at base. Larvae jumping. S. officinale: Contarinia symphyti
11c Flowers strongly swollen, especially in basal part. Calyx often conspicuously enlarged; corolla thickened, ± greened. Receptacle and ovary strongly swollen; containing several white beetle larvae. S. officinale: Ceutorhynchus sp.
Laatste bewerking 13.iv.2020
Dichotomous table for gallers on Stachys
1a On parts above ground => 2
1b Roots with small nodular or spindle-shaped swellings. S. sylvatica: Meloidogyne hapla
2a On inflorescences or flowers => 18
2b On vegetative plant parts => 3
3a Locally ± defined galls of stems or on leaves => 12
3b Malformations of shoot tips, on several leaves, or on expanded parts of leaf blades, often simultaneously on stems and other organs => 4
4a Malformations caused by animals => 6
4b Malformations caused by fungi with fruiting bodies at their surface => 5
5a The diseased basal- or more rarely stem leaves are paler and longer stalked than the healthy ones. On underside completely or extensively with scattered small brown sori, sometimes coalesced. S. officinalis & subsp. serotina, pradica: Puccinia betonicae
5b Similar, sometimes almost witches’ broom-like malformations on S. annua, recta: Puccinia vossii
5c Fungal down on the abnormally small, discoloured corolla. It consists of erect conidiophores that apically are branching dichotomously several times, each branch ending in a lemon-shaped conidium. S. palustris, recta: Peronospora jagei
6a Malformation of several leaves terminally on shoots => 7
6b Basal young shoots markedly stunted, conspicuously spongy, pale-green; leaf pairs densely clustered; leaf blades necrotic, similarly disfigured. S. arvensis, palustris, setifera: Ditylenchus dipsaci
7a Malformations caused by aphids and spittlebugs => 10
7b Malformations caused by gall mites or gall midge larvae => 8
8a Leaves clustered, bud- or rosette-like on main- or side shoots, also in leaf axils; galls lacking additional pubescence. Midge galls => 9
8b Stem terminally variously stunted, thickened and distorted; partially with ± excessive branching and leafiness; unfolding of leaves ± largely stunted; sometimes white-felt-like pubescent. Inflorescences and flowers, if present, severely disfigured. S. alpina, annua, officinalis & subsp. serotina, pradica, recta: Aceria solida
9a Inner leaves of end- or lateral buds severely stunted, not unfolding, often ± boat -shaped, bent and shrivelled; developing into a 15–35 mm long, pale, erect, irregular gall. Leaf blades of ± spreading leaves with cartilaginous, green-yellow roll of leaf margin. Larvae living also in disfigured inflorescences; dirty pale yellow to orange-coloured. S. alpina, palustris, recta, sylvatica: Wachtliella stachydis
9b Tip of main- and side shoots or axillary bud transformed into oval, converging loose leaf rosette. Containing several white larvae. S. alpina, palustris, recta, sylvatica: Wachtliella stachydis
10a Aphid galls => 11
10b Single or several terminal internodes usually stunted on one side, thickened and distorted. Stachys spp.: Philaenus spumarius
11a Leaves rolled inwards. Aphid 1.3–1.7 mm long, pale green. Siphunculi whitish with black tip. S. arvensis, cretica & subsp. salviifolia, officinalis, recta, sylvatica: Aphis stachydis
11b Leaves terminally clustered, rugose; transversely rolled downwards. Aphid about 1.5 (2.0) mm long, dark-green to dirty-yellow; siphunculi black. S. arvensis: Aphis gossypii
12a Galls on leaves => 15
12b Stem galls or galls exclusively on petioles => 13
13a Inducers inside malformations => 14
13b Stems, also basal parts of petioles ± bulging over a length of 20 (50) mm. S. officinalis, recta: Planchonia arabidis
14a Stem terminally almost globular; shoot tips atrophied and withering. Containing several larvae. S. alpina, officinalis, pradica, sylvatica: Thamnurgus kaltenbachii
14b Stem with several small pustules (procecidia: oviposition scars, not true galls) which wither after emergence of larvae. S. recta: Unidentified sawfly
15a Localised galls on leaf blades and sometimes additionally on stalks => 16
15b Petiole and leaf blade broadened at base, thickened, abnormally pubescent. S. officinalis: Unidentified gall midge
16a Bulge- or wart-shaped galls on leaf blade or on venation and stalks => 17
16b Leaf margin over ± large extent rolled upwards, irregular cartilaginous, pale-green. Containing orange larvae. S. alpina, palustris, recta, sylvatica: Wachtliella stachydis
17a Galls wart-like, less than 1 mm long, ± golden-yellow; many on underside of basal leaves, petioles and basal stem parts. S. officinalis: Synchytrium aureum
17b Small, weakly protruding, oblong-oval sori on main venation, petioles and young stems, bearing brown uredinia. S. annua, recta, sylvatica: Puccinia stachydis
18a Malformations limited to single or several flowers; axis of inflorescence usually not infected => 20
18b Malformation of complete or large parts of inflorescence => 19
19a Midrib ± stunted, thickened, distorted. Inflorescence compact, transformed into a rotund to oblong-oval ball. Calyx lobes often elongated. All infected green parts ± with white-felt-like pubescence. S. alpina, annua, officinalis & subsp. serotina, pradica, recta: Aceria solida
19b Flower buds ± clustered; unopened; only calyx swollen and enlarged. Corolla, stamens, pistil necrotic. Containing several orange-coloured larvae. S. alpina, palustris, recta, sylvatica: Wachtliella stachydis
20a Flower buds ± swollen, unopened. Midge galls => 21
20b Flowers outwardly hardly changed. Anthers at first swollen, soon destroyed by dark-violet, reticulate, later on dusting spores. S. alopecuros, maritima, officinalis, recta: Microbotryum betonicae
21a Galls thin-walled; internal mycelium absent => 22
21b Galls about 5–6 mm across. Inner wall with at first whitish, later on dirty grey, thick cotton-wool-like mycelium coating. Containing a single larva. S. recta: Asphondylia sp.
22a On S. officinalis. Buds distinctly swollen, unopened: Unidentified gall midge
22b On S. sylvatica. Larvae white, jumping: Ametrodiplosis crassinerva
Laatste bewerking 14.iv.2020
Dichotomous table for gallers on Secale
1a On above-ground parts => 4
1b On roots => 2
2a Roots with distinctly protruding galls => 3
2b Roots externally not noticeably changed. Later on often with many cysts, about poppy-seed size, at first white, then dark brown. Roots with giant cells inside. S. cereale: Heterodera avenae
3a Roots with many small, ± spindle-shaped swellings, about 1–6 mm long and 0.5–5 mm broad, crooked or screw-shaped, bent. S. cereale: Subanguina radicicola
3b Galls spindle-shaped, of similar size, but not screw-like, curved. S. cereale: Meloidogyne hapla
4a On spikes, florets or fruits => 15
4b On vegetative parts => 5
5a On leaves or culms of already ± developed shoots => 10
5b On young plants or on plants that are severely stunted by the infestation => 6
6a Central leaves of ± swollen shoots diseased and easily pulled out before dying off. On winter grain after a cold winter, often not before early spring, conspicuous infestation is distinguished by its excessive leafiness, which later develops further if not also infected. Pattern of damage of various inducers rather similar => 7
6b Basal parts of shoots strongly thickened, with elongate onion-like swelling. Plants excessively leafy; almost cushion-like shape; new shoots almost similarly infected. Leaf blades, especially of the inner leaves, ± ruffled and spirally twisted; at first dark green, then prematurely yellowing. S. cereale: Ditylenchus dipsaci
7 Malformations caused by ± cylindrical fly maggots with buccal hooks, which are at least 4 mm long when fully grown. Central leaves soon yellowing; at base ± disintegrated => 8
7b Young shoots of winter- and summer grain at base with several larvae of puparia; sometimes, if many present, slightly swollen. Leaf sheaths closely gathered together. Leaf blades often erect, often dark green, shorter and broader, as in healthy plants. Inner leaves later on withering, without conspicuous yellowing. Shoots developing further above the lower node sometimes slightly swollen and cracked. Spikes etiolated, sessile. Underneath the sheaths are several yellowish-white larvae, about 3 mm long, lacking buccal hooks, but with bifid sternal spatula; terminally conically narrowed, also with two narrowing papillae. Puparia brown, flax seed-like. S. cereale: Mayetiola destructor
8a Damage on summer as well as on winter cereals => 9
8b Damage on winter cereals only. Inner shoots in spring soft, with brown puparium at feeding site. Delia coarctata
9a Infected shoots severely stunted and ± swollen. Mature larvae about 4 mm long, yellowish-white; at the narrowed terminal part with 2 wart-like, flattened appendages, with a shallow indentation in between. S. cereale: Oscinella frit
9b With similar biology, also on rye, is the closely related Oscinella pusilla
9c Similar malformations. Mature larvae about 7 mm long, yellowish-white. Anal segment almost hemispherical to rotund-oval with 2 flattened appendages, leaving a flat, wide depression in between. S. cereale: Chlorops pumilionis
10a Malformations on leaf sheaths or culms caused by aphids or fungi => 14
10b Galls caused by apodous larvae developing inside culms or between culm and leaf sheath => 11
11a Larvae lacking sclerotised mouthparts, living on shoots between culm and leaf sheath => 12
11b Larvae in a furrow situated below the spike, in shortened and swollen internodes, protruding into younger culm parts. Spikes ± etiolated, often remaining in the occasionally partially spreading sheath of the upper leaf. Containing a single maggot up to 7 (9) mm long, with buccal hooks. S. cereale: Chlorops pumilionis
12a Culm slightly swollen at infestation site or with ± distinct depression. Larvae 3–4 mm long, yellowish-white or orange-coloured => 13
12b Leaf sheath above the upper internode, more rarely the penultimate internode, slightly inflated; several, elongated, rimmed, saddle-shaped depressions on culm, up to 10 mm long, each containing a single 3–5 mm brick red larva. S. cereale: Haplodiplosis marginata
13a Culm above the first, more rarely the second node, with one or two expanded, black-walled, oblong, slight depressions, each containing a single orange-yellow to brick red larva. S. cereale: Hybolasioptera fasciata
13b Culm stunted; sometimes, if many larvae or puparia present, slightly swollen inside the sometimes weakly swollen leaf sheath immediately above the first or second node. Containing one to several yellowish-white larvae or flax seed-like puparia. S. cereale: Mayetiola destructor
14a Upper leaves disfigured; sheath sometimes slightly swollen; leaf blade ± twisted. The only partially developing spikes are variously disfigured. S. cereale: Sitobion avenae
14b Occasionally causing similar malformations. S. cereale: Rhopalosiphum padi
14c Leaves, sheaths and culms with long, 1–1.5 mm broad stripes of smut, slightly protruding, at first lead-grey, then breaking open and releasing black-brown spores. S. cereale, montanum, strictum: Urocystis occulta
15a Malformations mainly of ovaries or fruits, parasites develop inside => 16
15b Malformations of various floral parts or complete spikes caused by animal parasites living on the host. Inducer unknown
16a The soon disfigured ovaries are filled with compact masses of dark smut spores => 17
16b Spikelets not spreading; diseased grains much smaller than normal ones ± rotund- to oblong-oval, 2–5 mm long, 1–2.5 mm broad, dark coloured, thick-walled, pale coloured inside and filled with many eelworms. Galls dropping off prematurely. S. cereale: Anguina tritici
17a Diseased plants not conspicuously shortened => 18
17b Infected plants grow only to half the normal length. Infestation often of all florets, with shortened ovaries usually developing into ± oval variable smut bodies and containing many reticulate spores, often enveloped by slime. S. cereale: Tilletia controversa
18a Smut grains much smaller than normal, egg-shaped to cylindrical, foul-smelling when fresh, usually all florets of a spike infected. Containing brown-black spores that later form a dusty powder. S. cereale: Tilletia secalis
18b Spikes often only partially infected, usually the lower or middle part. Glumes not spreading. Brown-black, later on dusty smut sori in the ovaries that are destroyed early in development, also in the lower part of glumes. S. cereale: Ustilago nuda f. sp. tritici
Laatste bewerking 12.iv.2020
Dichotomous table for gallers on Scabiosa
1a On parts above ground => 2
1b Roots with small cylindrical-spindle-shaped swellings, 3–4 mm long, and considerable formation of side roots: Meloidogyne hapla
2a Malformations of inflorescences or flowers => 11
2b Malformations on vegetative parts => 3
4a Malformations on leaves, with or without inclusion of tips or axial parts of shoots => 7
4b Galls on axial parts of shoots => 5
5a Inducers inside galls => 6
5b Stem locally stunted, with irregular spindle- or bulge-shaped swellings and often strongly distorted or irregularly bent, up to a right-angle; often with several rimmed depressions which contain scale insects below scales. S. ochroleuca: Planchonia arabidis
6a Shoot axis, especially at base, with nodular, succulent, dark red-brown swelling. Containing a caterpillar. S. atropurprurea, canescens, columbaria, ochroleuca, triandra: Alucita grammodactyla
6b Axial parts of flowering shoots with oblong-oval swelling, up to 4 mm long, often ± crimson-red. Containing a pale-yellow caterpillar with yellow-brown head. S. atropurprurea, canescens, columbaria, ochroleuca, triandra: Alucita grammodactyla
7a Galls with abnormal, ± white pubescence => 10
7b Malformations lacking conspicuous pubescence => 8
8a Malformations caused by aphids => 9
8b Leaves terminally on vegetative shoots ± distinctly clustered. Leaf blades narrowed and ± with protuberances. Scabiosa spp.: Aceria squalida
9a Shoot axis variously stunted. Leaves curved and curled. S. columbaria, ochroleuca, triandra: Aphis thomasi
9b Similar malformations. S. atropurpurea, columbaria, ochroleuca, triandra: Aphis confusa
10a Leaves sometimes densely clustered on tips of non-flowering sometimes stunted main and side shoots; leaf blades narrowed, rolled upwards, ± weaved and tuberculate, especially stunted basally and over often larger expansion ± densely white felt-like pubescent. In strongly infected plants also white erinea also locally on sometimes strongly swollen leaf- or stem parts. Also inflorescences may be severely stunted and white felt-like over large expansion. Scabiosa spp.: Aceria squalida
10b Inside leaf rosette two or more leaves remain erect. Their base is stunted, and severely stunted leaf blades are swollen, mussel-like, thickened and at least the basal part on both sides densely covered with long, white hairs, resulting in a compact gall. Sometimes with similar galls on lateral buds or tips of severely stunted shoots. Containing several white, later on ± reddened larvae. S. columbaria: Jaapiella scabiosae
11a Malformations lacking conspicuous additional pubescence => 12
11b All parts of still young, ± stalked capitula severely stunted and often densely pubescent. Exceptionally also further developed inflorescences affected, of which almost only the involucral bracts are ± disfigured and densely haired. Scabiosa spp.: Aceria squalida
12a Malformations caused by animals => 14
12b Malformations caused by fungi => 13
13a Anthers, sometimes also filaments, ± shortened and swollen, soon filled with dirty straw-coloured spore masses. S. columbaria & subsp. balcanica, lucida, ochroleuca, triandra: Microbotryum intermedium
13b Flowers variously stunted or distorted; sometimes with ± petal-like transformed anthers. Diseased parts soon covered with a loose, dark down of branched conidiophores. S. columbaria, lucida, ochroleuca: Peronospora violacea
14a Malformations of almost entire flower head => 15
14b On ± fully developed capitule, single to many involucral bracts are distinctly elongated, thread-like, rolled upwards, not additionally pubescent and often bumpy and curved. Also some greened receptacular bracts and even sexual organs may be similarly galled. Scabiosa spp.: Aceria squalida
15a Malformation of complete flower head. Flowers greened, ± stalked, and developing new shoots (phyllanthy). Scabiosa spp.: Aceria squalida
15b Flowers unopened, swollen. Containing several jumping midge larvae. S. columbaria: Contarinia scabiosae
Laatste bewerking 12.iv.2020
Dichotomous table for gallers on Saxifraga
1a In inflorescences, on flowers or their parts => 10
1b On stems and leaves => 2
2a Extensive or limited malformations on leaves, or localised swellings on stems => 4
2b Malformations involve extended parts of shoots => 3
3a Shoot tip disfigured, shortened, ± abnormally haired. Inflorescences, if present, with disfigured, leafy flowers. Excessive branching and leafiness. S. aizoides, mutata: Aculus kochi
3b Internodes shortened. Leaves on shoot tips clustered. Infected inflorescences disfigured. Flowers leafy. Mites free-living on organs. S. oppositifolia: Aceria saxifragae
4a Localised wart- or bulge-shaped galls caused by fungi => 7
4b Extensive malformations on leaves, sometimes on stems => 5
5a Malformations caused by animals => 6
5b Diseased leaf blades smaller, narrower, and paler than the healthy ones, and slightly thickened; on underside large areas are covered with loosely arranged, yellow sori. Buds, stem parts or inflorescence stalks, infected during development ± stunted and slightly swollen. S. cespitosa, granulata: Melampsora vernalis
6a Petiole of several rosette leaves shortened and spongy; leaf blade stunted and especially lower half, especially the veins, wrinkled, pale green. S. umbrosa: Ditylenchus dipsaci
6b Curling of basal leaves. S. granulata: Unidentified aphid
7a Galls pad- or spindle-shaped, several mm in size => 9
7b Galls wart-shaped, less than 1 mm long; sometimes ± coalescing => 8
8a Warts very small, punctiform, 1-celled, crimson-red. The nutritive cell protrudes only a little from the leaf surface, merely extending inside the host tissue. S. granulata: Synchytrium rubrocinctum
8b Nutritive cells enlarged, including neighbouring cells. Galls ± yellowish. S. aizoides, androsacea, bryoides, moschata, stellaris: Synchytrium saxifragae
9a Sori ± whitish- to greenish-yellow, visible on both leaf surfaces. Only exceptionally slightly swollen. Chlamydospores inside leaf, conidia developing on surface. S. ? aizoides, rocheliana, rotundifolia: Entyloma schinzianum
9b Similar infestations on S. paniculata, aspera, bryoides, oppositifolia: Arcticomyces warmingii
9c Sori dark brown, powdery or nodular, mainly prominent on underside, bulge-shaped swellings on leaf blade, leaf veins, -stalks; on stems in ± bulging sori causing distortions and bends. Teliospores striate. Saxifraga spp.: Puccinia saxifragae
10a Galls on flowers or ovaries => 11
10b Inflorescence ± shortened, spirally rolled inwards. S. paniculata: Unidentified lepidopteran
11a Malformations of ovary, containing a single midge larva => 13
11b Flowers ± leafy or swollen and unopened => 12
12a Flowers leafy, transformed into small rosettes. S. biflora, oppositifolia: Aceria saxifragae
12b Flower buds ± strongly swollen; broad egg-shaped, ± reddened, unopened. Containing several sulphur-yellow larvae. S. granulata: Dasineura saxifragae
13a Ovary greatly enlarged, thick-walled. Style stunted. Containing single pale red larva. S. aizoides: Unidentified gall midge
13b Ovary weakly swollen; infected flower shorter and more compact than the normal ones. Containing yellow-red larva. S. granulata: Unidentified gall midge
Laatste bewerking 10.iv.2020
Dichotomous table for gallers on Primula
1a On parts above ground => 2
1b On roots or root collar => 3
3a On inflorescences or flowers => 9
3b On leaves => 4
3c Whole plant disfigured, covered by a down of branched conidiophores. P. acaulis, auricula, elatior, veris: Peronospora oerteliana
4a Leaf blades strongly curled, margin rolled, warts, pads, bulges or spongy, swollen galls on leaves and stems => 8
4b Malformation usually of several rosette leaves caused by the perennial mycelium of monoecious rust fungi. Leaves paler and slightly longer stalked than healthy ones, rigidly erect, soon covered with sori. Primula spp.: Uromyces primulae-integrifoliae
5a Warts, pads or bulges caused by fungi => 8
5b More or less expanded parts with spongy swellings; also curling of leaf blades or rolling of leaf margin => 6
6a Leaf blades curved, curled or margins rolled => 7
6b Whole plant ± stunted. Leaves shortened, especially swollen at base and at veins. Often with various swellings also on inflorescence. Flowers variously swollen and leafy. Primula spp.: Ditylenchus dipsaci
7a Leaf margin narrowly rolled upwards. P. auricula: Unidentified gall mite
7b Leaf blades to large extent often obliquely rolled downwards over the tip, hunched up and arched, dark green close to infestation. A single or several froth-covered nymphs on underside. Primula spp.: Philaenus spumarius
8a Basal leaf parts and venation with many solitary or variously joined, multicellular golden-yellow warts, less than 1 mm long. P. elatior, veris: Synchytrium aureum
8b Leaf underside with rotund aecia bearing pads, on veins ± elongated, yellow, sometimes weakly swollen. Aecia cup-shaped with deflected, lacerate border. P. acaulis, elatior, grandiflora, veris: Puccinia primulae
9a Ovary moderately to belly-like swollen. Seed primordia swollen => 11
9b Malformation of almost all flower parts => 10
10a Flowers variously disfigured. Corolla often greened; also anthers and pistil variously greened; leafiness. These malformations also on plants which bear spongy bulgings on other parts. P. denticulata & var. cashmeriana, florindae, rosea, veris: Ditylenchus dipsaci
10b Calyx tube-shaped elongate, sometimes inflated. Corolla calyx-like transformed, green. Ovary swollen, protruding from flower; seed primordia transformed into minute leaf-like structures. P. florindae: Subanguina klebahni
11a Seed primordia at first hypertrophied, later on filled with masses of blackish, irregular rotund to oblong spore balls. Ovary slightly swollen. Infestation of flowers inconspicuous from the outside. P. acaulis, elatior & subsp. intricata, veris & subspp. canescens + columnae + macrocalyx, vulgaris: Urocystis primulae
11b With similar biology on P. farinosa, stricta, veris & subsp. columnae: Urocystis primulicola
Laatste bewerking 10.iv.2020
Dichotomous table for gallers on Pisum
1a On root collar or on above ground organ => 4
1b On roots => 2
2a Roots with nodules => 3
2b Root system and shoot parts ± atrophied; roots unchanged on the outside, giant cells inside; later on bearing poppy-seed sized, lemon-shaped, whitish to brownish egg capsules. Pisum spp.: Heterodera goettingiana
= Also recorded on Pisum species is the clover cyst eelworm H. trifolii. More strongly infected plants often lacking nodules
3a Roots slender or nodular swellings bearing side roots. Pisum spp.: Meloidogyne hapla
3b Oval or cylindrical nodules, often terminally broadened and ± forked or lobed, hand-shaped or coralline-like subdivided, at maturity inside ± flesh-red, up to about 8 mm long, occasionally clustered; laterally inserted on main- and side roots. Pisum spp.: Rhizobium leguminosarum
4a On flowers or fruits => 11
4b On vegetative parts => 5
5a On aerial organs => 7
5b On root collar => 6
6a Proliferations conspicuous, closed, at surface not subdivided. “oot cancer”. P. sativum: Agrobacterium tumefaciens
6b Witches’ broom-like malformation. Accumulation of severely stunted or fleshly thickened, lobed, pale, aerially greening shoots. “Leafy gall”. P. sativum: Rhodococcus fascians
7a Older plants ± severely stunted, leaves and, when present, flowers variously disfigured, or malformations of shoot tips => 8
7b Stems of young plants severely stunted, often conspicuously spongy thickened and ± distorted. Lateral organs stunted, ± bent and curled at base, also swollen; growth dwarfed. Pisum spp.: Ditylenchus dipsaci
7c Shoot distorted, often with proliferation of buds and russeting of leaves. Pisum spp.: Peronospora viciae
8a Plant completely or largely disfigured => 9
8b Shoot tips stunted to variable degree, leaves including, if present, disfigured flower buds, rosette-like or bushy accumulations, containing many white jumping larvae. P. sativum: Contarinia pisi
9a Malformations caused by aphids => 10
9b Leaves on the ± atrophied shoot tip curled, rolled upwards; leaves and flowers, if present, clustered. If strongly infected, the plant remains small and bushy; larvae very slender, many, up to about 1.5 mm long. Pisum spp.: Thrips angusticeps
10a Several leaves of variously disfigured shoot tips; the leaf blades ± curled and deflected, partially discoloured; containing black aphids Pisum spp.: Aphis fabae
10b Similar malformations caused by green aphids. P. sativum: Acyrthosiphon pisum
11a On flowers => 12
11b Young pods disfigured, sometimes with nodular, discoloured swellings. Usually containing many white, jumping larvae. P. sativum: Contarinia pisi
12a Flower buds disfigured and clustered on often severely stunted stalks, especially swollen at base, corolla stunted and strongly curled, unopened; containing many white, jumping larvae. P. sativum: Contarinia pisi
12b Flowers developing into short shoots with scale-like, green leaflets. P. sativum: Unidentified gall mite or virus
Laatste bewerking 2.viii.2020
Dichotomous table for gallers on Pinus
1a On above-ground parts => 2
1b Roots of seedlings distinctly shortened, with nodular swellings or proliferations. Bark loose around central cylinder with eelworms in between. Parts above ground shrivelled. P. sylvestris: Unidentified root eelworm
2a On shoots or needles => 4
2b On cones => 3
3a Cones shrivelled, bent, stone hard, not opening, always ± acuminate. Irregular tunnels in scale bases; already dropping 8–10. Usually a single, sometimes 2 or 3 larvae. P. cembra, mugo, nigra, pinea, ponderosa, sylvestris: Pissodes validirostris
3b One-sided curved cones, with resin and frass, containing caterpillars. P. nigra, sylvestris: Cydia conicolana
3c Cone scales inside with elongated wart-like swellings. P. sylvestris, strobus: Kaltenbachiola strobi
3d Blister-like swellings on cone scales caused by spermogonia and aecia of rust. P. densiflora, sylvestris, virginiana: Cronartium quercuum
4a On shoot axial parts => 7
4b On needles => 5
5a Needles swollen at base => 6
5b Needles accumulated terminally on young shoots, development stunted, undulately curved or bent screw-like, not thickened. Pinus spp.: Pineus pini
5c Fungus. Both surfaces of needles with cylindrical projections of aecia (I), 1–5 mm long; spermogonia present. Pinus spp.: Coleosporium tussilaginis
6a Infestation of developing needles. They are severely shortened, their bases ± fused over a length of 2–3 mm, swollen, sometimes slightly twisted, erect and in autumn often golden-yellow. Larvae 2–3.5 mm long, orange-reddish to red, lacking sternal spatula; one or occasionally more larvae per gall. P. halepensis, mugo & subsp. rotundata, nigra, pinaster, pinea, sylvestris: Thecodiplosis brachyntera
= The pine needle buckling gall midge Contarinia baeri causes needles constricted at base and bend like walking sticks, dropping already in autumn
6b Needles remain linked, with yellowish, bulging thickenings, shortened, often ± twisted screw-like; a basal, expanded, bag-like widening containing a whitish to yellow beetle larva. P. sylvestris, uncinata: Brachonyx pineti
7a On stems, older branches or several year old twigs => 10
7b On young shoots => 8
8a Galls caused by animals => 9
8b Bark of young twigs usually with narrow erupting pads on one side 10–30 mm long, with dusting of reddish-yellow spores. Shoots stunted at infestation site, continuing to grow on healthy side and so deflected. Terminal parts become erect subsequently making s-shaped curves. Pinus spp.: Melampsora populnea
9a Axis gaping over a length of about 20–30 mm, ± swollen. Primary bark and resin channels enlarged; secondary bark and wood slightly thickened. Pith cavity containing a large-headed, yellow- to yellow-brown caterpillar. Open gall often covered with resin mass on one side. P. banksiana, mugo, pinaster, sylvestris: Retinia resinella
= The gall midge: Cecidomyia sarae has been recorded from resin lumps and wounds caused by R. resinella
= Two more gall midges, Cecidomyia pini and C. harrisi, occur also in resin exudates of shoots and green cones of P. pinaster, sylvestris without causing malformations. The species differ in larval characters, viz., spatula, dorsal lobes on abdomen.
9b Caterpillars at first in lower pith of young, stunted shoot tips or buds, sometimes thickened on one side, crooked, later on dehiscing. Pinus spp.: Rhyacionia buoliana
= the larvae of several leafrollers live as borers in the buds and young shoots of pine trees, causing rather similar damage symptoms. Of the more rare species the biology is not known in sufficient detail to enable discrimination, but at least the equally frequent Pseudococcyx turionella should be considered as a potential causer. The larva of Rhyacionia buoliana bores a tunnel from the base of a shoot upwards; this causes the shoot to bend (“posthorn shoot”); when this happens to the main shoot this causes a permanent bend in the trunk later. The larva of P. turionella empties a terminal bud, then burrows for a short distance downwards. Lateral buds around the dead terminal bud then get the opportunity to develop into shoots, causing a splaying or forking of the branch.
9c Young shoot curved and distorted, growth stunted. P. peuce, sibirica, strobus, sylvestris: Pineus strobi
10a Stems or branches with nodular swellings or with proliferations, excessive branching or witches’ brooms => 13
10b Bark of thinner plant parts usually swollen on all sides, several cm long, later on with many, pale yellow blister-shaped swellings, about pea-size, from which yellow fungus spores escape after eruption => 11
11a On P. mugo, sylvestris and other pines with paired needles => 12
11b On P. strobus (cult.) and other 5-needle whorled pines: Cronartium ribicola
12a Fungus host alternating. Aecia conspicuous, often many on 10–20 cm long swellings of twigs. Galls at thickest part sometimes with twice the normal diameter. Fewer on stems and young trees than on branches: Cronartium flaccidum
= Blister-like swellings on bark caused by spermogonia and aecia of rust. P. sylvestris: Cronartium quercuum
12b Fungus not host alternating; it develops haploid aecia in its sori, which are only able to infect Pinus. Galls as for pine blister rust. P. sylvestris:
Endocronartium pini
13a Malformation of complete shoots or witches’ brooms => 16
13a Nodule-, tuber- or spindle-shaped malformations => 14
15a Smaller, up to about 15 (30) mm globular, cancer-like compact nodules on the thicker twigs of P. cembra. “Twig tuberculosis”. Cause unknown – ? bacterium
15b On younger, thin twigs oblong to rotund, at first glabrous, later on rugose, up to 20 (25) mm broad and 10 mm high, yellow-brown swellings, permeated by many channels, originating from proliferation of the bark and persisting for several years. P. mugo, nigra, strobus, sylvestris: Trisetacus pini
16a Slightly extended malformation of complete shoots; proliferation and accumulation of buds. “Budding witches’ broom”. P. cembra, mugo: Trisetacus cembrae
16b Usually voluminous, loose, expanded or smaller, almost globular compact witches’ brooms, especially on P. sylvestris, as well as on some cultivated foreign pines. Inducer unknown
Laatste bewerking 9.iv.2020
Dichotomous table for gallers on Picris
1a On above-ground parts => 2
1b Roots with nodule-shaped swellings. P. hieracioides: Meloidogyne hapla
2a On vegetative parts => 3
2b On inflorescences => 15
3a On leaves => 9
3b On stems, shoot tips or buds => 4
3c All parts of shoot with white crusty blisters, very variable in size; shoot often distorted; P. echioides, hieracioides: Pustula obtusata
4a Galls on stems, on upper shoot tips or lateral buds => 5
4b Shoot formation in the leaf rosette deformed to a conical, 5 mm long, 9 mm wide gall, with several markedly shortened leaves. Containing one maggot. P. hieracioides: Napomyza lateralis
5a Malformations on stems, sometimes encroaching upon neighbouring buds or lateral shoots => 6
5b Tip of the main- or lateral shoot, also the axillary bud, deformed into rotund or oblong, galls up to 15 mm long, consisting of several strongly pubescent, short imbricated covered leaves. Containing several whitish, non-jumping larvae. Sometimes neighbouring stem parts galled. P. hieracioides: Jaapiella picridis
5c These galls may also contain jumping larvae of Contarinia picridis
6a The gall causers develop outside the galls in pit-like depressions or in erinea => 8
6b The gall causers develop inside the galls => 7
7a Galls of spongy nature; distinct from the outside. Early infected stems often mostly stunted in their longitudinal growth markedly swollen over substantial length, ± bent. Later infection results in ± curved localised swellings of different types, sometimes even including the often irregularly swollen receptacle. P. hieracioides: Ditylenchus dipsaci
7b Longitudinal growth of stem not – or rarely stunted, the outside hardly deformed. In the locally thickened pith are many separated elliptical chambers, about 1–2 mm long each with one larva. P. hieracioides: Unidentified gall wasp
7c Similar galls, but with larger chambers, 2.5–3 mm long each with a white larva, on P. echioides, hieracioides: Phanacis caulicola
8a Especially the basal stem part over various length ± bulging swollen, with one or several depressions containing the gall causer. P. hieracioides: Planchonia arabidis
8b Any part of stem with ± extended, dense, initially white or reddish, later brownish erinea. Sometimes the buds are involved, in which case they are to a large extent stunted. P. hieracioides: Aceria picridis
9a Galls predominantly on leaves, on the mid- and lateral main veins extended in various ways into the leaf blades or malformations exclusively on the petioles => 10
9b Leaves stunted in their development, in various ways curled, with loose, abnormal, pubescence. Between the narrow folds are yellowish, jumping larvae. P. hieracioides & subsp. spinulosa: Contarinia picridis
9c Basal leaves disfigured and curled. P. hieracioides: Protaphis terricola
10a Malformations without conspicuous pubescence => 11
10b Leaves with dense, initially whitish, later reddish, finally brownish erinea of multicellular, twisted hairs often on curved petioles and midribs. Pubescence of varied coverage on the under- or, more often, upperside, of the often curled, or even bulging leaf blade and even protruding onto the neighbouring mostly stunted axillary buds. P. hieracioides: Aceria picridis
11a Swellings spindle-shaped, usually less than 1 cm long, caused by fungi which fruit either inside the gall or on its surface => 13
11b Galls usually more expanded, caused by animal parasites, living inside the galls => 12
12a Galls spongy, usually pale green, sometimes reddened with ± wrinkled surface; in various ways protruding from the petiole or main vein into the ± distorted leaf blade. P. hieracioides: Ditylenchus dipsaci
12b Petiole, along with the basal parts of the main vein, distinctly swollen, predominantly on the underside. Gall glabrous, gradually narrowed towards leaf tip. One larva. P. hieracioides: Phytomyza picridocecis
13a The fruiting bodies of the fungus develop inside the galls => 14
13b Midrib on the leaf underside often with several weak swellings, about 2–5 mm long, sometimes coalescing, often yellow-bordered, occasionally resulting in a distortion of the stems, on the underside soon occupied by brown sori. Pycnidia yellowish and on the upperside. P. hieracioides: Puccinia hieracii
14a alls on the main-, and the lateral leaf veins. Veins particularly swollen on ± irregularly bordered, often yellowish, sometimes reddish discoloured, leaf blade areas on the leaf underside, appearing as a distinctly protruding relief. Spores develop within and close to the vascular bundle. P. hieracioides: Protomyces picridis
14b Small, prominent, closed swellings on the main veins, up to 3 (5) mm long, mostly yellow-bordered, whitish to brownish. P. hieracioides: Entyloma picridis
15a Receptacle transformed into an irregular, multi-chambered woody swelling, nut-size. Sometimes the peduncle of the flower head is inflated. Larval chambers spherical, scattered. Helminthotheca aculeata: Timaspis helminthiae
15b Receptacle transformed into a hard, multilocular mass, 8-‒17 x 14‒20 mm, like the rest of the plant covered with a coarse bristly hair cover. Gall chambers 3‒10. Helminthotheca comosa & subsp. lusitanica: Phanacis comosae
15c On flower heads. Helminthotheca echioides; Picris hieracioides: Tephritis divisa
Laatste bewerking 8.iv.2020
Dichotomous table for gallers on Hypericum
1a On above-ground parts => 3
1b On subterranean parts => 2
2a Subterranean buds unopened, egg-shaped, consisting of succulent, yellowish, ± lanceolate scales. Containing 2–5 larvae per gall. H. maculatum, perforatum, pulchrum: Geocrypta braueri
2b oots with nodular to spindle-shaped swellings. H. calycinum: Meloidogyne hapla
3a Terminally on vegetative shoots, on leaves, inflorescences or flowers => 4
3b Axial part of shoot with irregular swellings, bearing single or several rimmed depressions and each containing a flat froth-covered nymph. H. perforatum, pulchrum: Planchonia arabidis
4a On inflorescences or flowers => 14
4b On vegetative parts => 5
5a On leaves => 11
5b Terminally on shoots => 6
6a Galls of ± definite shape on terminal buds of side- and main shoots => 8
6b Expanded malformations of undefined shape terminally on shoots => 7
7a Complete plant ± stunted, sometimes dwarfed with excessive branching; leaves narrower, more acute and densely arranged, pale; glands ± disfigured. H. perforatum: Cause unknown – ? gall mite
7b Shoot axis variously stunted, locally ± buckled, partially intensive green. Hypericum spp.: Philaenus spumarius
8a Galls tuft-like or acuminated,-cylindrical => 9
8b Galls ± globose, usually reddish, consisting of the terminal, distinctly shortened and widened, completely galled pair of leaves. Containing several reddish-yellow to red larvae. Hypericum spp.: Zeuxidiplosis giardi
9a Caused by gall midges => 10
9b Small tufts of leaves, caused by aphids; accompanied by excessive leafiness and distortion of stem. Hypericum spp.: Aphis chloris
10a Several terminal leaves imbricated clustered, tuft- or bud-like. Gall rotund in outline, leaves erect, keel-shaped, basally ± strongly thickened, sometimes yellowish or reddish; apical part often hardly changed. Containing several, at first white, later on pale to darker red coloured larvae. Hypericum spp.: Dasineura hyperici
10b Both terminal leaf pairs remain closed together and form a pointed-cylindrical gall, ± bilaterally symmetrical in cross-section, often reddened, hollow inside. Containing several white to yellowish larvae. Hypericum spp.: Dasineura serotina
11a Malformations of complete leaf blade caused by animals => 12
11b Leaf blade with ± many, yellow translucent many-celled warts, less than 1 mm long, variously joined; also on stem parts. H. perforatum: Synchytrium aureum
12a The additionally variously disfigured leaves are rolled at margin => 13
12b Veins of the discoloured and disfigured leaf are thickened and undulating. H. perforatum: Unidentified gall mite
13a Leaves curled, upwardly rolled; containing a single white midge larva. H. maculatum, perforatum: Unidentified gall midge
13b Leaf blade strongly wrinkled and ± folded, with downward roll of leaf margin. H. hirsutum, maculatum, montanum, perforatum: Aculus hyperici
13c Tight downward roll of leaf margin; roll more pubescent than the rest of the leaf blade, containing several white larvae. H. hirsutum, perforatum: Macrolabis marteli
14a Galls on single flowers => 15
14b Flowers clustered, ±, greened; bracts irregularly curled and rolled inwards; small leafy shoots are often clustered and bushy. H. maculatum, perforatum: Unidentified gall mite
15a Flower buds unopened. Galls rotund; caused by gall midges => 16
15b Corolla leaves unopened, developing into an acuminate gall, in longitudinal direction ± flattened, later on brown striate. Containing a single caterpillar. H. hirsutum, perforatum: Lathronympha strigana
16a Buds swollen, reddened; containing several white larvae. Hypericum spp.: Dasineura serotina
16b Buds especially swollen at base; from wide base short acuminate; ± striate and reddened. Containing white, jumping larvae. H. maculatum, perforatum: Contarinia hyperici
Laatste bewerking 8.iv.2020
Dichotomous table for gallers on Corylus
2a On catkins or fruits => 13
2b On vegetative organs => 3
3a On leaves => 9
3b On buds, young shoots or older branches => 4
4a On buds and young shoots => 7
4b On woody parts => 5
5a Cancers or witches’ brooms => 6
5b Thicker branches or stems with ± distinct nodular to club-shaped swellings. Corylus cornuta: Viscum album
6a Bark of woody parts with cancer-like proliferations. C. avellana: Neonectria ditissima
6b Small witches’ broom-like malformations. C. avellana: Cause unknown – ? gall mite
7a On young shoots => 8
7b Buds swollen, rotund, up to 10 mm long. Scales enlarged, thickened like the outer leaf primordia and inside with tubercular proliferations. C. americana, avellana, colurna, maxima: Phytoptus avellanae
7c Enlarged globular bud. Contains caterpillar in a large central cavity. C. avellana: Unidentified lepidopteran
8a Young shoots stunted. Usually leaves of several buds per twig are disfigured; their leaf blades curled, folded, partially rolled and more densely pubescent. C. avellana: Cecidophyopsis vermiformis
8b Young shoot with local, pustule-shaped swellings; apical part of shoot ring-barked, withering and soon breaking off. C. avellana, colurna: Oberea linearis
9a Leaves folded or curled => 11
9b Leaf blades with flat, rotund archings => 10
10a Flat upward proliferations, surrounded by a 6 mm long, slightly discoloured and thickened area; the underside cavity contains a single vitreous to whitish larva. C. avellana, maxima: Mikomya coryli
10b Leaf blade with parenchyma galls about 3–5 mm wide, weakly protruding on both sides, initially hardly discoloured. Containing a single larva. C. avellana, colurna, maxima: ? Arnoldiola tympanifex
11a Leaf blade curled => 12
11b Leaf blade folded and crumpled; at base, with white, jumping larvae. C. avellana: Contarinia cybelae
12a Younger leaves, if heavily infected, folded and curled. With green, rarely reddish, ca. 2.5 mm long aphids on the underside. C. avellana, colurna, maxima: Corylobium avellanae
12b Younger leaves, if heavily infested, with discoloured bulges. With pale yellow to yellowish-white, ± 2 mm long aphids on underside. C. avellana, colurna, heterophylla, maxima: Myzocallis coryli
12c Leaf blades loosely contracted together, curled. C. avellana: Philaenus spumarius
13a Malformations of the catkins => 14
13b Gall-like malformations in the developing fruits, from the outside inconspicuously changed. C. avellana: Curculio nucum
14a Catkins completely or only partially swollen => 15
14b Catkins sprouting. C. avellana: Unidentified gall mite
15a Catkins locally or completely pear- or barrel-shaped, swollen. Scales enlarged, glabrous; stamens ± stunted, larvae white, glossy, jumping. C. avellana, maxima Contarinia coryli
15b In similar galls. Larvae white, dull, non-jumping. Inquilines of the previous species: Dasineura corylina
15c Catkins locally swollen, often at their base. Scales ± irregular, sometimes elongated, lacerate, ± pubescent, slightly thickened, spreading at top. Stamens enlarged. C. avellana: Phyllocoptruta coryli
15d Male catkins distorted, often twisted screw-like. Containing one to several caterpillars. C. avellana, ? colurna: Unidentified lepidopteran
Laatste bewerking 7.iv.2020
Dichotomous table for gallers on Cornus
1a On leaves => 3
1b On stems => 2
1c lowers slightly swollen and remaining closed, containing a whitish to light orange larva. On C. sanguinea: Unknown gall midge
2a Small, ± rotund-oval, rimmed depressions on bark of ± swollen twig parts. Cornus spp.: Chionaspis salicis
2b Thick branches with ± spindle-shaped, mistletoe bearing swellings. Cornus spp.: Viscum album
3a Malformations of undefined expansion, caused by aphids or free-living mites => 5
3b Galls of ± defined shape, small, wart-, or pustule-like, or conspicuous, ± blunt-conical => 4
4a Galls larger than 1 mm. Leaves on midrib, mainly on lower side veins, usually with several, 3–5 mm broad, often many-chambered, tough-walled, greenish or ± reddened galls; basally blunt-conical, top surrounded by 2–5 or more lobes; protruding on upper side as a ± hemispherical bump. Each chamber containing a single orange-yellow to -reddish larva. C. mas, sanguinea & subsp. australis: Craneiobia corni
4b Hardly 1 mm long, yellow translucent small warts, usually many on basal green organs. C. sanguinea: Synchytrium aureum
5a Malformations caused by aphids => 7
5b Malformations caused by mites => 6
7a Aphids yellowish, greenish to red-brownish => 8
7b Aphids black. Terminal leaves ± rolled inwards, slightly curled. C. sanguinea: Aphis fabae
8a Aphid powdered, long haired, on midrib of leaf underside usually arranged in rows. Terminal leaves loosely clustered, nest-like. C. alba, sanguinea, sericea:
Aphis salicariae
8b Aphid not powdered, up to 2.5 mm long. Antennae half the body length. Siphunculi pore-shaped. Leaves, if strongly infected, stunted, curled, rolled, sometimes keel-shaped, deflected. C. alba, glabrata, mas, sanguinea: Anoecia corni
8c Very similar aphid. Causing similar malformations facultatively on C. sanguinea: Anoecia vagans
Laatste bewerking 6.iv.2020
Dichotomous table for gallers on Carum
1a On parts above ground => 2
1b Roots with nodular swellings. C. carvi: Meloidogyne hapla
2a On inflorescences, flowers or fruits => 12
2b On vegetative parts => 3
3a Galls bulging, bearing aecia on surface => 11
3b Aecia absent, differently shaped => 4
4a Galls caused by animal inducers or by fungi, fruiting inside => 5
4b Basal leaves variously disfigured. Leaf blades ± arched, soon with expanded areas of grey-white asci. C. carvi: Taphridium umbelliferarum
5a Malformations extended over large parts of leaves => 9
5b Malformations of various expansions on leaf-axis or leaf veins, hardly 1 mm across, wart-shaped => 6
6a Swelling of axis, usually ± exceeding 2 mm => 8
6b Galls ± hemispherical, wart-shaped, usually on leaf underside, on midrib and stalk; sometimes coalesced into smaller ridges or crusts. Perennial spores only in a central strongly swollen nutritive cell surrounded by enlarged auxiliary cells => 7
8a Compact, glabrous, pale green, vitreous, spindle-shaped bulges, about 2–15 mm long on leaf veins and midrib, -stalk and young stem. Many spores close to vascular bundle. C. carvi: Protomyces macrosporus
8b Stalk and midrib ± severely stunted and spongy, swollen. Galls yellow-green, soft, wrinkled at surface, usually over large expansion at lower stem parts and basal leaves; sometimes also as localised bulge on leaf midrib as well as on stem. C. carvi, verticillatum: Ditylenchus dipsaci
9a Leaf blade curled, caused by aphids or cercopids => 10
9b Tip of leaf broadened, thickened, shortened and deflected or enlarged and lacerate; sometimes clustered bush-like due to stunting of midrib. C. carvi: Aceria carvi
10a Leaves converging downwards ± nest-like; curled and deep green close to the froth-covered nymph. Carum spp.: Philaenus spumarius
10b Leaves slightly curled and discoloured, often initially etiolated. Aphid pale green, with bifid cauda. C. carvi: Cavariella aegopodii
11a Leaf veins, -midrib, -stalk or also stem with bulges bearing yellowish spermogonia and aecia. Aecia pustule-shaped, with round exit hole. C. carvi: Puccinia bistortae
11b Only aecia formed, these cup-shaped, with frayed, whitish border. C. carvi: Puccinia polygoni-alpini
12a On inflorescences or flowers => 13
12b Fruit bladder-like swollen, often ± reddened, protruding above the umbel. Containing 1 (‒3) orange-red larvae. C. carvi, verticillatum: Kiefferia pericarpiicola
13a Malformations on expanded parts of umbel => 14
13b Stalks at centre or close to (partial) umbel ± swollen club-shaped or globular. Galls one-, also multi-chambered. Inner wall with mycelium. Each chamber contains a single larva. C. carvi, verticillatum: Lasioptera carophila
14a Inflorescence variously stunted and tangled, flowers stunted => 15
14b Inflorescence severely disfigured. Many parts of flowers leafy, corolla sometimes greened, also discoloured whitish-green or reddish. C. carvi: Aceria carvi
15a Stalks of young inflorescence variously stunted, also distorted. (Partial) umbels ± tangled. Flowers stunted and disfigured. Contain froth-covered nymph. Carum spp.: Philaenus spumarius
15b Similar malformations on young inflorescence caused by many aphids. C. carvi: Hyadaphis foeniculi
Laatste bewerking 5.iv.2020
Dichotomous table for gallers on Carpinus
1a On above-ground parts => 2
1b Root with nodule-shaped swellings. C. betulus: Meloidogyne hapla
2a On leaves or buds, also on fruit wings => 5
2b On stems or branches => 3
3a Conspicuously protruding from the bark => 4
3b Bark initially with closed, irregular crooked proliferations, bursting open later on, displaying the woody part surrounded by variously shaped cancers. “Nectria-cancer”. C. betulus: Neonectria ditissima
4a Localised thickenings and sometimes distortion of branches or stems. C. betulus: Viscum album
4b Heavier branches or stems with bushy, up to 1 m large witches’ brooms, with thickened and densely foliate branched axial parts. Leaf blades curled; asci on the undersides June-August. C. betulus, orientalis: Taphrina carpini
5a On leaves and occasionally on the envelope of the fruit => 7
5b On buds => 6
6a Buds swollen, not opening; spherical or egg-shaped, partially pea-size swollen. Scales grey-white pubescent. C. betulus: Unidentified gall mite
6b Buds swollen, enlarged, not developing. Contain yellow larvae. C. betulus: Contarinia trotteri
7a Galls on the leaf blades or in the vein axils of unfolded leaves => 11
7b Swelling of the veins or leaf blade heavily folded or curled => 8
7c Leaves browning. C. betulus: Aculus betuli
8a Venation involved in the malformations => 9
8b Leaf blade between two side veins with a somewhat thickened, pod-like, ± yellowish or usually red upward fold; on the underside a furrow which opens at maturity. Contains several white larvae. C. betulus, orientalis: Contarinia carpini
8c Occasionally also observed in galls of Contarinia carpini are the yellow larvae of Aschistonyx carpinicolus
9a Venation with conspicuous thickenings => 10
9b Side veins and the neighbouring, upward folded parts of the leaf blade conspicuously ± zigzag-like bent in- and outwards. Heavily infected leaf blades ± rolled upwards. C. betulus, orientalis: Aculops macrotrichus
10a Leaves folded upward over the uniform, only slightly thickened midrib. Infestation often extending into the base of the also slightly thickened side veins, sometimes only locally, the neighbouring leaf blade parts fold subsequently. Midrib of early affected leaves usually bent downwards. On the upper side, especially on the midrib, a single- or several yellowish larvae. C. betulus, orientalis: Aschistonyx carpinicolus
10b Midrib and the adjacent parts of the side veins on the leaf underside with conspicuous, interrupted or continuous, in that case bumpy swellings. Leaf blade sometimes over the midrib ± bent upwards. Galls with a double row of chambers on both sides of the midrib. In each chamber, situated between two side veins, a single yellowish-white larva. C. betulus: Zygiobia carpini
11a Malformations without particular connection with the venation => 12
11b Leaf blade in the vein axils at the upper side weakly arched, sometimes discoloured ± purple-red; with corresponding depressions, at their margin conspicuous very long twisted hairs, on the underside. C. betulus, orientalis: Aceria tenella
= Putative inquiline: Phyllocoptes compressus
12a Leaf blade with small, rotund, hardly arched, pale green or yellowish parenchyma galls, up to 4 mm wide. Containing one single yellow larva. C. betulus: Dasineura ruebsaameni
12b Underside of leaf blade with erinea. C. betulus, orientalis: Cecidophyopsis vermiformis
Laatste bewerking 5.iv.2020
Dichotomous table for gallers on Alopecurus
2a On inflorescences or fruits => 9
2b Complete host disfigured or malformations on stems or leaves => 3
3a Leaves or sheaths with localised or expanded malformations or with long stripes caused by smuts => 6
3b Main shoot of host stunted and disfigured => 4
4a Malformations caused by fly- or midge larvae => 5
4b Plant growth stunted. Inflorescence remains hidden in the swollen leaf sheaths, pale. A. pratensis: Limothrips denticornis
= Stem gall above internode on A. pratensis is caused by the eurytomid Tetramesa fumipennis
5a Stem shortened with weak swelling below the emerging inflorescence. A. myosuroides, pratensis: Oscinella frit
= On the same hosts the closely related Oscinella alopecuri and O. ventricosi have been described
5a Leaf sheaths usually inflated above the upper node. On stem above the nodes one or several saddle-shaped margined galls, which contain in each depression an intensely red larva. A. myosuroides: Haplodiplosis marginata
5c Yellow midge larvae develop under leaf sheaths at stem base. A. pratensis: Mayetiola alopecuri
6a Leaf blades and sheaths with smut patches => 8
6b Malformations caused by animal parasites => 7
7a Leaf sheaths inflated, bladder-like, sometimes discoloured violet and locally slightly thickened. A. geniculatus, pratensis: Rhopalosiphum padi
7b Leaf blade at base with narrow, elongate-cylindrical swellings. A. geniculatus: Unidentified eelworm
7c Upper leaf swollen, bladder-like, discoloured. Aphid up to 2 mm long, slim. A. geniculatus, pratensis: Laingia psammae
8a Elongate patches, at first lead grey, then dusty, on leaves, rarely on stems. Spores usually 2–3, in balls enveloped by sterile cells. A. aequalis, arundinaceus, geniculatus, myosuroides, pratensis: Urocystis alopecuri
8b Smut patches in black stripes, later on completely shredded leaves, on sheaths and stems. Spores solitary, globular, densely covered with small blunt warts. A. arundinaceus, geniculatus: Ustilago striiformis
8c From A. gerardii has been described: Tilletia sleumeri
9a Inflorescences disfigured over extensive areas => 11
9b Malformations predominantly restricted to ovaries and neighbouring glumes => 10
10a Infected ovaries transformed into a compact smut body, sometimes larger than a normal seed. A. myosuroides: Tilletia controversa
10b Ovaries swollen, tube-shaped elongated, inside with spongy tissues or with expanded cavities. Glumes ± conspicuously enlarged. A. alpinus: ? Anguina sp.
10c Seeds destroyed on account of the puncturing of the ovary by the larva. A. agrestis, pratensis: Dasineura alopecuri
10d Midge larvae live gregariously in inflorescences. A. pratensis: Contarinia merceri
10e Ditto, A. arundinaceus, geniculatus, myosuroides, pratensis: Stenodiplosis geniculati
11a Spikelets variously completely or partially disfigured by aphids. A. arundinaceus, pratensis: Sitobion avenae
11b Similar malformations. A. arundinaeus, pratensis: Sitobion fragariae
11c Spikes leafy, over expanded parts ± greened or, in case of strong infestation, bleached. A. pratensis: Aceria tenuis
Laatste bewerking 2.iv.2020
Dichotomous table for gallers on Chaerophyllum
1a On parts of inflorescence or fruits => 15
1b On stems or leaves => 2
2a Bulge-shaped, usually yellowish coloured or margined galls on leaves or stems, soon bearing fruiting bodies of rust fungi on their surface => 10
2b Malformations caused by animal parasites or by fungi, fruiting inside the gal => 3
3a Malformations on leaves caused by aphids => 7
3b Malformations caused by different parasites => 4
4a Leaves variously folded, curled or distorted => 5
4b ulge-like, depending on the infected plant part, variously large, compact, pale-green swellings on leaf veins, -midrib, or shoot axis, exceptionally even on young fruits. Containing fungus spores inside. Ch. hirsutum, villarsii: Protomyces macrosporus
5a Leaves disfigured on leaf blades and midrib => 6
5b Development of leaves completely stunted; midrib normal; only the leaf blade folded upward, ± curled and thickened close to midrib. Containing several white larvae. Ch. aromaticum, hirsutum: Macrolabis heraclei
6a Main- and side axis ± stunted, the ± developed leaves deflected, with their ± curled leaf blades loosely converging, nest-like. Leaf blades close to infestation deep-green. Chaerophyllum spp.: Philaenus spumarius
6b Mainly apical parts of leaves stunted and distorted, leaf blades locally swollen, curled. Malformation stunted, often inconspicuously converging, nest-like. Ch. temulum: Trioza apicalis
7a Aphids green => 8
7b Aphids black. Leaflets curled and converging; upper stem leaves slightly bleached. Ch. bulbosum: Aphis fabae
8a Aphids yellowish-green to green, siphunculi of same colour, long, slightly swollen => 9
8b Aphid greenish, siphunculi black, long, swollen. Ch. aromaticum, hirsutum, temulum: Hyadaphis foeniculi
9a Aphid with a “double” cauda; antennae not reaching the middle of body. Leaves curved and curled; the inflorescence is often simultaneously infected and distorted. Ch. temulum: Cavariella pastinacae
9b Cauda simple, antennae longer than half the body length; leaves curled, sometimes reddened at margin; usually only slightly curled. Ch. hirsutum: Myzus persicae
10a Bulges on leaves and stems caused by a fungus, developing aecia => 12
10b Fungus develops only telia; leaf axis and stem, also stalk of umbel, with 1–2 mm long pads, which often coalesce to ± conspicuous and curved, bulging swellings => 11
10c Leaves blistered, especially when young, with whitish down on underside. Ch. aromaticum, aureum, bulbosum, temulum: Plasmopara chaerophylli
12a Aecia on Ch. aromaticum or bulbosum, rarely aureum => 14
12b Aecia on Ch. aureum, hirsutum, temulum => 13
13a On Ch. hirsutum. Fungus develops on swollen, orange-red pads, only spermogonia and deeply countersunk, not protruding, pustule-shaped aecia: Puccinia bistortae
13b Aecia pustule-shaped, with rather weakly developed, loose peridium, with outer wall not, or weakly thickened. Chaerophyllum spp.: Puccinia chaerophylli
14a Aecia in dense groups, on leaf underside on arched spots or often in long pads on veins, midrib, stalks or on stems. Peridium weakly developed, loose, opening with an oblong slit. Ch. aromaticum: Puccinia aromatica
14b Aecia pustule-shaped, caeoma-like, opening with oblong slit, cells of peridium similar to spores. Ch. aureum, bulbosum, coloratum, hirsutum, temulum: Puccinia retifera
15a On fruits => 16
15b Centre of stalk of (partial) umbel ± swollen club-shaped or globular. Containing a red larva. Ch. aromaticum, bulbosum, temulum: Lasioptera carophila
16a Fruit bladder-like, inflated, ± globular, protruding above the umbel. Containing an orange-red larva. Ch. aromaticum: Kiefferia pericarpiicola
16b Fruit tube-like, swollen. Containing a white-yellow larva. Ch. bulbosum: Unidentified gall midge
Laatste bewerking 1.iv.2020
Dichotomous table for gallers on Mentha
1a On parts above ground => 2
1b Nodular swellings on roots bearing side roots. Mentha spp.: Meloidogyne hapla
2a On inflorescences or flowers => 12
2b On vegetative organs => 3
3a Various malformations on shoots or leaves => 7
3b Localised galls of different size on stems or leaves => 4
4a Wart- or bulge-shaped galls caused by fungi => 5
4b Egg-shaped or conical galls, 4–6 mm long, 2–3 mm thick, often reddened swellings of shoot axis, usually situated above a higher node. Containing a curved larva, yellow when mature. M. aquatica, arvensis, pulegium, suaveolens: Squamapion vicinum
5a Galls contain spores => 6
5b Strongly swollen, sometimes conspicuously curved, yellowish or brownish-green bulges on basal stem parts; pads on leaf blades protruding on underside, on upperside often ± depressed, yellow, ± red-margined. Galls soon bearing cups, with dust of reddish-yellow spores. Mentha spp.: Puccinia menthae
6a Less than 1 mm long, golden-yellow translucent, multi-cellular warts on leaf underside, on petioles and stems; often many and occasionally joined into crusts or ridges. M. aquatica, longifolia: Synchytrium aureum
= On leaves of M. aquatica small, irregular globular or oval, often reddened nodules with a central cavity may be caused by the green alga Chlorochytrium rubrum.
6b Thick, black-brown bulges on stems, rarely on leaves, containing dark brown spore masses. M. aquatica: Physoderma menthae
7a At shoot tips or on leaves => 8
7b Plants stunted. Stem at base with bases of inserted leaves strongly swollen and spongy. Gall ± pale-green, necrotic. Mentha spp.: Ditylenchus dipsaci
8a Malformations not excessively pubescent => 10
8b Malformations covered by dense, abnormal pubescence => 9
9a Leaves or, if present, also neighbouring flower buds stalked on tips of main- and side shoots; all organs with ± dense yellowish-white pubescence on all sides. Hairs multi-cellular, branched. Sometimes excessively leafy, branched. Mentha spp.: Aceria megacera
9b Leaf blades of slightly stunted leaves with dense whitish pubescence. M. aquatica, arvensis, longifolia, mollissima, spicata: Aceria mentharia
10a Malformations caused by aphids => 11
10b Clustering of several leaves on bent shoot tips, usually stunted on one side and ± rolled and curled. Mentha spp.: Philaenus spumarius
11a Leaves on shoot tip strongly curled. Aphid green. Mentha spp.: Aphis affinis
11b Leaf blades of terminal leaves strongly curved and deflected. Aphid greenish-white. Mentha spp.: Ovatus crataegarius
12a Malformations of inflorescence => 14
12b Malformations on single or several flowers => 13
13a Flower buds swollen, unopened. Inner wall with mycelium. Containing an ochre-yellow larva. Mentha spp.: Asphondylia menthae
13b Flow ers slightly disfigured, only recognisable if closely examined. Mentha spp.: Peronospora stigmaticola
14a Malformations abnormally densely pubescent => 15
14b Malformations without abnormal pubescence. Accumulations of slightly stunted bracts and severely disfigured flowers at shoot tip of Mentha spp.: Eriophyes menthae
15a Flowers, mainly of terminal inflorescences, transformed into dense, white-pubescent, greened structures. Mentha spp.: Aceria megacera
15b Similar galls on M. arvensis, longifolia: Aceria mentharia
Laatste bewerking 16.vii.2020
Dichotomous table for gallers on Lolium
1a On above-ground parts => 3
1b On roots => 2
2a Roots often with many slender galls, up to about 5 mm long and 0.5–4 mm thick, usually bent or twisted half screw-like. L. perenne: Subanguina radicicola
2b Roots from the outside hardly changed, inside with giant cells, temporarily occupied by white to brown, about poppy-seed size cysts. Lolium spp.: Heterodera avenae
3a On inflorescences, flowers or fruits => 8
3b On culms, shoot tips or leaves => 4
4a Malformations on culms, shoot tips or leaves => 5
4b Complete plant stunted, disfigured, often additionally leaf-like, shoots often reddish discoloured, especially thickened close to ground. Leaves shortened, bent and rugose. L. multiflorum, perenne: Ditylenchus dipsaci
4c Growth compact and stunted, spikes disfigured, however, many shoots remain healthy. L. perenne: Steneotarsonemus spirifex
5a Malformations on leaf blades => 7
5b Malformations on culms or shoot tips => 6
6a Saddle-shaped depressions, about 10–12 mm long, elongated, raised at the ends above the terminal node, covered by slightly swollen leaf sheaths. Each gall containing a brick-red larva. L. temulentum: Haplodiplosis marginata
6b Occasionally on L. multiflorum, perenne occurring as various malformations: Oscinella frit
6c Terminal tuft of imbricate leaves, discoloured, stem not swollen. L. perenne: Tetramesa sp.
6d Whitish, at surface yellowish or brownish patches, which envelope a large area of the upper part of stem, of which further development is stunted. Node of stem rarely swollen, encircled by fungus stroma, yellowish when mature; several nodes may be affected; flowering stunted; stroma contains narrow asci and filamentous spores. L. multiflorum, perenne: Epichloë typhina
7a Leaves rolled, plant ± severely stunted. L. multiflorum, perenne: Diuraphis frequens
7b Leaf blade, sheath and occasionally culm with long parallel stripes caused by smut. L. perenne: Urocystis bolivarii
7c Spores solitary, brown-black, globular or rotund-oval. L. perenne: Ustilago striiformis
7d Long conspicuous stripes on chlorotic leaf tissue caused by rust fungus. L. perenne: Puccinia striiformis
8a Malformations of inflorescences or their stalks => 9
8b Yellow larvae live gregariously in the inflorescences. L. perenne: Contarinia lolii
8c Ovaries distinctly swollen, transformed into a ± egg-shaped, acuminate structure, filled with a yellowish to yellowish-brown spore mass, foul-smelling when fresh. Lolium multiflorum, perenne, remotum, rigidum, temulentum: Tilletia lolii
9a Spikelets developing further, floral parts variously greened or leaf-like, in other cases bleached. L. perenne: Aceria tenuis
9b Lateral spindle-shaped swelling at base of inflorescence stalk. L. perenne: Tetramesa sp.
Laatste bewerking 2.vii.2020
Dichotomous table for gallers on Lactuca
1a On above-ground parts => 2
1b Mostly terminal parts of root with nodular swellings. L. perennis, sativa, serriola: Meloidogyne hapla
2a Malformations of inflorescences or capitula => 11
2b Galls on shoots or leaves => 3
3a Malformations almost exclusively on leaves => 6
3b Malformations on stems, with or without involvement of leaves => 4
4a Localised galls on shoots => 5
4b The overwintering mycelium causes a systemic infection, largely deforming the plant and inhibiting the formation of flowers. Internodes lanky, often excessively elongated, diseased stems ± prostrate; affected leaves pale green, shortened and on the underside, like the stems, with spermogonia and isolated aecia on expanded areas. Lactuca sibirica, Mulgedium tataricum: Puccinia minussensis
5a Shoots with spindle-shaped to oval or elongated bulges, with single to many depressions containing the gall causer. L. serriola, viminea: Planchonia arabidis
5b Conspicuous stem galls, about 30–45 mm long, 10–20 wide tuber- to spindle-shaped, tough. L. saligna, viminea: Timaspis phoenixopodos
6a Malformations mainly of the leaf blades => 8
6b Galls exclusively or preferentially on the petiole or on the midrib => 7
7a Conspicuous swelling of the midrib of basal leaves, especially protruding on the underside, glabrous on the surface, broad at the base, gradually narrowing, usually extending into the upper third of the leaf blade. Containing a single larva. L. serriola: Phytomyza penicilla
7b Spongy, ± spindle-shaped swellings of the midrib in different sites and of various expansion. Surface mostly rugose, inside massive. Occasionally extending into the leaf blade, which is often swollen and disfigured. L. serriola: Ditylenchus dipsaci
7c Midrib of leaf over a length of 8–15 mm swollen, blister-like and slightly bent; on the underside with dense rows of aecia and pycnidia, which may also appear scattered on the upper side. L. alpina, aurea, macrophylla: Puccinia mulgedii
8a Local, ± conspicuous swellings on the leaves caused by rust fungi => 10
8b Expanded malformations of the leaf blade => 9
9a Compact, narrow upward roll of the leaf margin. L. perennis: Unidentified gall mite
9b Leaf blade ± curled and discoloured. L. sativa, serriola: Nasonovia ribisnigri
= Sometimes occurring together with the aphid Aulacorthum solani
10a Leaf blade with 5–10 (15) mm long rotund, pale green to reddish spots, usually on the underside with a vivid yellowish hardly swollen pad bearing cup-shaped aecia; with a corresponding depression on the upper side. L. perennis, quercina, sativa, serriola, virosa, etc.: Puccinia opizii
10b Aecia with pore-shaped opening, unlike the cup-shaped opening of the preceding species, the peridium very loose, rudimentary. Sori on the underside of the leaves, on the leaf blades usually rather small and little swollen; on the venation, petioles and stems united in larger groups on bulge-like swellings. L. perennis, serriola, rarer on L. perennis, quercina, sativa, serriola, viminea: Puccinia lactucarum
10c On L. viminea with similar aecia to the preceding species: Puccinia maculosa
11a Stalks of young inflorescences or the basal parts of older inflorescences markedly stunted in longitudinal direction; ± thickened; budding inflorescences in various numbers at their base ± globular or mostly obtuse cone-shaped swollen; not opening. On later infected inflorescences the stalks are less stunted; finally only some to many disfigured capitula are distributed over the inflorescences. Containing many white, jumping larvae. L. serriola: Contarinia cf. salatica
11b Capitula often completely transformed into small tufts of irregular, curved leaflets. L. saligna, sativa, serriola, virosa: Aculus lactucae
11c Flower head remaining closed, swollen and longitudinal-ovoid. L. viminea: Hypenidium graecum
Laatste bewerking 29.iii.2020
Dichotomous table for gallers on Hypochaeris
1a On capitula or achenes => 14
1b On vegetative plant parts => 2
2a On leaves => 5
2b On stems => 3
2c All parts of shoot with white crusty blisters, very variable in size; shoot often distorted. H. maculata: Pustula obtusata
3a Shoot axis with tough-walled, plurilocular galls => 4
3b Shoot axis with spongy pale green galls of various shape, length and position, usually on all sides, often elongate, massive, ± twisted or curved. Close to the capitula, also extending into the receptacle. H. maculata, radicata: Ditylenchus dipsaci
4a Stem with up to 40 mm long and 7 mm thick, plurilocular, usually spindle-shaped or oblong swelling, sometimes occupying the whole shoot axis. Galls in spring; one yellow larva per chamber. H. achyrophorus, glabra, laevigata, radicata: Phanacis hypochoeridis
4b Shoot axis, often at the stem base, with one-sided callosity, up to 5 mm long with rotund larval chamber. Hypochaeris spp.: Napomyza lateralis
5a Galls on the leaf blade, not involving veins => 11
5b Galls on main- or secondary veins, partially extending to the leaf blade; massive => 6
6a The gall development expands from the midrib to the leaf blade, or affects mainly the secondary venation => 7
6b The gall formation is restricted to the vein => 7
7a Spongy, short spindle-shaped galls, but variously elongated, protruding on both sides of the vein, pale green with ± rugose surface, often extending over a wide area of the leaf blade, occasionally also running only from the major lateral veins and causing bends. Many eelworms inside the loose gall parenchyma. H. glabra, maculata, radicata, uniflora: Ditylenchus dipsaci
7b Venation of irregularly margined and pale- or yellow green upward arched areas swollen, often ± reddened, the underside protruding in relief. Many spores in the vascular tissue. H. radicata: Protomyces cf. kriegerianus
8a Elongated soft swelling, emerging at the leaf base and narrowed towards the top, is caused by fly maggots => 10
8b Up to 6 mm long swelling, especially prominent on one side of the leaf => 9
9a Closed, egg-shaped, thin- but tough-walled, unilocular swelling. H. glabra, maculata, radicata: Aulacidea andrei
9b Inconspicuous swellings, up to 2 mm long, ± egg-shaped, yellow margined with covering of cinnamon brown spores, usually on the underside of the youngest, ± curved leaves. H. glabra, radicata, maculata: Puccinia hieracii
9c Similarly has been recorded on H. uniflora the close relative: Puccinia montivaga
9d Similarly on H. achyrophorus the close relative: Puccinia marquesii
10a About 3 (5) cm long occasionally slightly reddened galls on smaller leaves which are sometimes extending to the upper side of the terminal third part of the leaf blade. H. radicata: Phytomyza cecidonomia
10b Corresponding galls in the larger leaves, hardly conspicuous, on H. maculata: Phytomyza sp.
11a Galls lacking additional pubescence => 12
11b Leaf blade folded and reddened; in the folds on the upperside white, felt-like, pubescence, might be accompanied by rolling of the leaf margin. H. glabra, radicata: Aceria hypochoerina
12a Galls on expanded leaf blade => 13
12b Leaf blade upward folded, containing apterous green aphids about 1 mm long. H. maculata, radicata: Aphis hypochoeridis
13a Leaf blade slightly deformed, with irregular, weak, one-sided open bulges. H. radicata: Craspedolepta flavipennis
13b Leaf blade with several distinctly protruding pustules on the upperside, which are surrounded by a broad yellow-green to reddish margin. On the leaf underside clearly recognizable red-yellow larva is situated in spongy parenchyma under the epidermis. H. glabra, radicata: Cystiphora sp.
14a Malformations of the capitula => 16
14b Malformations of the achenes => 15
15a Capitula disfigured, with patch of stunted florets and their achenes at side of receptacle; containing yellow, jumping larvae. H. glabra, maculata, radicata: Contarinia hypochoeridis
15b Achene deformed to a 3 mm long, rotund-oval longitudinally grooved gall. One white larva. H. radicata: Unidentified tephritid fly
16a Capitula small and not opening, swollen. H. uniflora: ? Stylia sp.
16b In ungalled capitula of Hieracium spp.: Campiglossa achyrophori
Laatste bewerking 26.v.2020
Dichotomous table for gallers on Chenopodium
1a On parts above ground => 3
1b On roots => 2
2a Roots with small, nodular or spindle-shaped, compact swellings, up to about 4 mm long. Chenopodium album; Dysphania ambrosioides; Lipandra polysperma: Meloidogyne hapla
2b Outside of root unchanged, inside with giant cells. C. album: Heterodera schachtii
= On Oxybasis glauca the clover cyst eelworm Heterodera trifolii has been recorded
2c Main root close to ground surface with conspicuous, easily rupturing, 30 to 80 mm long, 5–6 mm thick, beet-like thickening, with a broad, elongate cavity usually containing several larvae. Chenopodium spp. s.l.: Bothynoderes affinis
3a Leaves with abnormal pubescence or with down-like sori of fungi => 12
3b Malformations not conspicuously pubescent or without down-like sori => 4
4a Extensive malformations caused by aphids, spittlebugs or psyllids => 9
4b Causers belong to other groups => 5
5a Single galls pearl-like, on leaves, often also on stems; sometimes, on greatly disfigured organs, coalescing into ± expanded ridge- or crust-like groups => 8
5b Malformations extensive, of indefinite shape => 6
6 Galls predominantly on stem parts => 7
6b Infected shoots or complete plants growing abnormally, ± crippled, almost witches’ broom-like. Leaves ± erect and distorted, narrower than those on healthy plants. Flower buds slightly inflated, at first unopened, often densely aggregated, their ovaries soon filled with a grey-brown, later on dusty spore mass. Chenopodium album, strictum; Dysphania ambrosioides: Thecaphora leptideum
7a Shoot axis, depending on grade of infestation, ± bulge-like swollen over various lengths; with rotund-oval, rimmed depressions containing causer. Chenopodiastrum hybridum: Planchonia arabidis
7b Galls broad spindle-shaped or narrowing barrel-shaped; up to hazelnut-size. Inside are several oblong larval chambers. Each chamber contains a single yolk-yellow or red larva. C. album: Aplonyx chenopodii
7c Stem parts of young plants distinctly shortened, spongy, swollen. Inserted leaves with shortened, thickened stalks and veins, leaf blades variously disfigured. Chenopodium album, foliosum, Lipandra polysperma: Ditylenchus dipsaci
= Terminally bushy, compact plants of Chenopodiastrum murale with oblong, slightly spindle-shaped stem galls with an expanded frass-containing pith channel. Cf. Scrobipalpa obsoletella
8a Leaves and stems, rarely also perigone, with 1–2 mm long or more expanded, multicellular, wart-like, ± hemispherical, watery- or yellow-green, curly galls which in the case of more dense infestation, join into larger bulges on the often conspicuously distorted axial leaf parts or margins, as well as on stem parts. Chenopodium spp. s.l.: Physoderma pulposum
8b Single galls hardly 1 mm across, golden-yellow translucent, on underside of basal leaves, their stalks and stems. Chenopodium album, Lipandra glauca, Oxybasis rubra: Synchytrium aureum
9a Malformations contain aphids => 11
9b Malformations caused by psyllids or spittlebugs => 10
10a Leaf blades with irregular leaf folds, caused by froth-covered nymphs of psyllids. Chenopodium spp. s.l.: Heterotrioza chenopodii/p>
10b Leaf blades variously ± nest-like deflected, hunch-backed curled, dark green close to the froth-covered nymph. C. bonus-henricus, etc.: Philaenus spumarius
11a eaves on the ± shortened shoot tips converging, their leaf blades stunted, variously also deflected over their tip; infected inflorescences clustered, globular. Aphid black. Chenopodium spp. s.l.: Aphis fabae
11b Leaves upwardly folded along midrib or rolled, often distinctly thickened and severely discoloured. Aphid about 1.5 mm long, green, conspicuously frosted with white powdery wax. Chenopodium spp. s.l.: Hayhurstia atriplicis
12a Leaves lacking bladder-like swellings, abnormally pubescent. Hairs simple, not branched fork-like. C. album: Unidentified gall mite
12b Leaf blade with ± expanded, sometimes considerably, pale green, occasionally violet discoloured, bladder-like, partially distinctly thickened swellings, on underside a dense dirty-violet down of multiple fork-like branched conidiophores. Fungi belong to the species complex of Peronospora farinosa
Laatste bewerking 27.iii.2020
Dichotomous table for gallers on Matricaria
1a On above-ground parts => 2
1b Roots with spindle- to nodule- shaped swellings, bearing several lateral roots. Matricaria chamomilla, Tripleurospermum inodorum: Meloidogyne hapla
2a On inflorescences or their organs => 9
2b On vegetative parts => 3
3a Localised galls on leaflets => 8
3b Malformations of leaves, single shoots or the complete plant => 4
4a Various malformations of leaves and shoots => 7
4b Development of entire plant or large parts of it stunted and variously disfigured; caused by aphids => 5
5a Aphids black => 6
5b Aphid yellow to yellow-green, 1.5–2 mm long. Matricaria chamomilla, Tripleurospermum inodorum: Brachycaudus helichrysi
6a More frequent inhabitant of disfigured plants. Matricaria chamomilla, Tripleurospermum inodorum: Aphis fabae
6b Similar development and only distinguished by microscopical characters. Matricaria chamomilla, Tripleurospermum inodorum: Aphis fabae subsp. solanella
6c Dense bushy growth. Matricaria chamomilla: Didymaria matricariae
7a Stems variously spongy, swollen, pale green, with ± rugose surface. Tripleurospermum inodorum: Ditylenchus dipsaci
7b Galls in apical meristems of rosettes and bolting plants, axillary leaf buds. Tripleurospermum inodorum: Rhopalomyia tripleurospermi
7c Downward bend, ± disfigured, locally dark green coloured leaves clustered in sometimes unilaterally curved terminal shoots. Matricaria chamomilla, Tripleurospermum inodorum: Philaenus spumarius
8a Hyaline, pale green, clearly protruding bulges on the leaflets. Tripleurospermum inodorum: Protomyces matricariae
8b Small rotund to oblong, diffuse or coalescing sometimes slightly thickened spots on leaves, conspicuous by their initially white, later on yellow to brown colour. Matricaria chamomilla; Tripleurospermum inodorum, maritimum: Entyloma matricariae
9a Galls in single florets or achenes => 14
9b Malformations on more substantial parts of the capitula => 10
10a Malformations predominantly of the receptacle => 12
10b Malformations predominantly of the florets => 11
10c Galls in different meristematic tissues of flower heads. Tripleurospermum inodorum: Rhopalomyia tripleurospermi
11a Ligules not developed. Flower head transformed into a semi-globular or elongated, 5–50 mm long greened and leafy tuft. Matricaria chamomilla; Tripleurospermum inodorum: cf. Aceria matricariae
11b Ligules elongated and variously curved; tubular florets ± withered. Organs soon covered with a loose grey cover of conidiophores. Matricaria chamomilla, discoidea; Tripleurospermum inodorum, maritimum: Peronospora radii
12a Considerable swelling of the receptacle => 13
12b Receptacle only slightly swollen, ± disfigured, hardened by a beetle larva. Matricaria chamomilla: Microplontus rugulosus
= Larvae of the leafminer Napomyza lateralis are rather frequent in receptacles of Tripleurospermum inodorum
13a Receptacle enlarged, thickened and arched. A yellowish-white maggot. Matricaria chamomilla, discoidea; Tripleurospermum inodorum, maritimum: Trupanea stellata
13b Similar, globular to egg-shaped receptacle gall inhabited by a beetle larva. Matricaria chamomilla; Tripleurospermum inodorum: Omphalapion laevigatum
= Also in capitula of chamomiles the larvae of other snout beetles develop, e.g., Omphalapion hookerorum
14a Single florets transformed into a hard barrel-shaped, glabrous gall, firmly attached to, or embedded in the receptacle, apically opening by a lid. Often several in a flower head. Containing a single larva. Tripleurospermum inodorum: Rhopalomyia syngenesiae
14b Achene swollen and base of corolla enlarged, often several affected in one flower head; each containing a yellow larva. Tripleurospermum inodorum: Ozirhincus longicollis
14c Similar malformations and biology similar to that of O. longicollis. Tripleurospermum inodorum: Ozirhincus hungaricus
Laatste bewerking 30.iv.2020
Dichotomous table for gallers on Genista
1a On parts above ground => 2
1b Rotund-oval to cylindrical, about 8 (10) mm long, apically ± forked or fan-shaped broadened, laterally attached nodules on main- and adventitious roots. Genista spp.: Rhizobium leguminosarum
2a On inflorescences, flowers or fruits => 15
2b On vegetative parts => 3
3a On shoot tip or -axis => 9
3b On lateral buds or leaves => 4
4a On buds => 7
4b On leaf blades => 5
5a Wart- or pustule-shaped galls on leaf blade => 6
5b Leaflet rolled over its length, slightly thickened and enlarged, ± yellowish or reddish, strongly pubescent. Galls usually with several terminally on non-flowering shoots. Containing a single white larva. G. pilosa: Dasineura genistarum
6a Compact, ± yellowish translucent warts on basal leaves; infestation encroaching onto young axial parts. G. tinctoria: Synchytrium aureum
6b Soft egg-shaped pustules, up to 2 mm long, ± yellowish-green. The emerged larva leaves the ‘procecidium’ (oviposition scar, not a true gall, which collapses soon afterwards) and feeds freely on the leaf blade. G. pilosa, tinctoria, etc.: Unidentified sawfly
7a Relatively small midge galls, up to 7 mm long, rather constant in shape, glabrous or sometimes in young stage ± strongly white pubescent => 8
7b The buds develop into small, ± witches’ broom-like structures bearing clustered, almost scale-shaped, strongly pubescent leaves. Genista spp.: Aceria genistae
8a Axillary leaf bud transformed into a glabrous gall, about 7 mm long, 4 mm thick, with large central chamber. Inner wall covered with mycelium. Containing a single larva. Genista spp.: Asphondylia genistae
8b Buds enlarged, transformed into an egg-shaped to oblong-oval tuft; with external white pubescence, at first bud-like, then apically spreading; containing one to several, at first white, later on pale pink-coloured larvae. Genista spp.: Jaapiella genisticola
8c Globular galls covered with long snow-white hairs at shoot tip or in leaf axil. G. scorpius: Dasineura scorpii
9a Galls exclusively or mainly on the buds or leaves of apical shoots => 10
9b The terminal axial parts are transformed over several, ± strongly shortened internodes into a broad, long-, rarely rotund-oval, irregular bulging, spongy, sparsely haired swelling; usually multiple-, rarely single-chambered. Tips of terminal and, if present, lateral shoots often with tuft-like clustered, ± reduced, basally thickened leaves. Larvae flesh-coloured, jumping. G. corsica, depressa, germanica, tinctoria: Contarinia melanocera
9c Terminal internodes shortened, excessively branched, bearing clustered tufts of small leaves, up to 3 mm long, underside pubescent, leaf blade wrinkled at top or curved, spoon-like. Malformation up to 20 mm across. Genista spp.: Aceria genistae
9d One-sided swelling of twig (10 x 3 mm), crazed at surface, with oblong larval chamber inside. G. aetnensis, tinctoria: Hexomyza cf. sarothamni
9e Internodes shortened, bearing enlarged, densely white pubescent leaves which are clustered in a rosette. G. scorpius: Dasineura scorpii
9f Subterranean part of stem with one-sided, discoloured malformations of variable length and shape, single or clustered in irregular complexes due to expansion of parenchyma; compact. Caused by large numbers of black aphids. Genista spp.: Aphis cytisorum
10a Tufts of leaves on G. sagittalis => 14
10b Tufts of leaves on other Genista species => 11
11a Tufts abnormally haired => 12
11b Leaves of tufts glabrous, basally thickened and broadened. Many larvae. G. germanica, tinctoria: Dasineura sp.
12a Malformations caused by gall midges => 13
12b Axis of shoot tip distinctly shortened. Apical- and usually some lateral buds developing into stub-shaped, partially branched shoots bearing markedly reduced, almost scale-shaped and densely haired clustered leaves. Genista spp.: Aceria genistae
13a Oblong, abnormally haired tuft of leaves on G. januensis, pilosa, tintoria. Leaves ± keel-shaped rolled inwards. Containing orange-coloured larvae: Jaapiella genistamtorquens
13b Acuminate rotund to oblong-oval, about 10 (15) mm long tufts of leaves with ± thickened, partially almost mussel-like broadened leaves and sometimes densely, short, white pubescent. Larvae at first white, then pale pink. Genista spp.: Jaapiella genisticola
14a Dense white or grey pubescent tufts of leaves. The upper leaves ± keel-shaped. Winged ridges of stem undulately bent: Aculus acraspis
14b Upper leaf enlarged and curved, enveloping a cluster of disfigured leaves, less strongly pubescent and mainly enveloped by a larger leaf: Dasineura cytisi
15a Fruit galls => 18
15b Galls on single flower buds or on ± expanded parts of inflorescence => 16
16a Several up to all flowers disfigured => 17
16b Flower buds swollen, unopened, calyx swollen. Corolla and anthers aborted. 4–5 yellowish-white larvae. G. sagittalis: Dasineura sp.
16c Similar galls, contain jumping midge larvae. G. hirsuta, sagittalis: Contarinia sp.
17a Caused by gall midges. Usually only a part of the flower bud is galled. This is swollen, unopened; strongly pubescent, like the enlarged bracts. Larvae at first white, then pink-coloured. Genista spp.: Jaapiella genisticola
17b Caused by gall mites. Inflorescence distinctly shortened. Flowers largely leafy, with abnormal white pubescence. G. sagittalis: Aculus acraspis
17c Caused by gall mites. Flowers greened. G. tinctoria: Phyllocoptes genistae
18a No layer of mycelium inside fruit galls => 19
18b Fruit galls caused by midges, with layer of mycelium inside. Pod swollen, egg-shaped to cylindrical. Seeds aborted. Containing 1 (‒3) orange-red larvae. Genista spp.: Asphondylia genistae
= Similar gall on G. sagittalis is caused by Asphondylia bitensis. One to three red larvae, or pupae, in the galled pods. Inner wall of gall chamber lined with mycelium
19a On G. pilosa. The pods are of almost normal size but infestation is indicated by weak, discoloured tubercles. Larvae bone-coloured: Contarinia pulchripes
19b On G. tinctoria, sagittalis. The young pod is distinctly swollen and often remains hidden in the hypertrophied, unopened flower. Containing a single larva: Tychius parallelus
= Swollen pods may be caused by weevil larvae of Exapion difficile and E. genistae; it is not known whether these are true galls
Laatste bewerking 25.iii.2020
Dichotomous table for gallers on Erigeron
1a Malformations locally => 2
1b Whole plant stunted in development, bushy, terminal part of stems stunted; leaves clustered, white-spotted, sometimes ± curved. Erigeron spp.:
Brachycaudus helichrysi
2a In capitula and fruits => 12
2b On vegetative parts => 3
3a Swellings of the stem, not in the terminal parts => 11
3b Galls in basal rosettes, in buds, growing points or leaves => 4
4a On shoot tips or leaves => 6
4b Galls of various kinds in stunted or on stunted rosettes or lateral buds; tuft of leaves variously developed or even missing => 5
5a Galls ± onion-like, swellings succulent, predominantly, at least in the rosettes, with tuft of leaves and sometimes lateral shoot. E. acris, uniflorus: Rhopalomyia ruebsaameni
5b Inner rosette leaves converted into a rotund or long-oval, up to 10 mm long, spongy gall. E. acris, uniflorus: Rhopalomyia ruebsaameni
6a Leaves with localised galls or occurring over larger areas with several galls, malformed predominantly in the terminal part of the shoot => 7
6b Leaves accumulated on the shoot tips tuft-like, at the base ± shell-like broadened, pale, the outer ones often reddened, their terminal parts ± stunted, but not conspicuously deformed or discoloured. E. acris: Dasineura erigerontis
7a Leaf blade over large parts rolled, curved or curled => 9
7b Leaves with restricted, wart- or bulge-shaped swellings => 8
8a Galls often many, less than 1 mm long, yellowish, sometimes coalescing. E. canadensis: Synchytrium aureum
8b Leaf veins and stems with black-brown dusty sori on weakly swollen bulges. Erigeron spp.: Puccinia dovrensis
9a Leaf blade loosely rolled inwards and curled; by aphids => 10
9b Top and margin of the leaf blades of the larger basal leaves bent together; stem leaves with several correspondingly deformed and often nest-like clusters on the locally stunted and ± curved stem. Close to the froth-covered nymph curled and dark green. Erigeron spp.: Philaenus spumarius
11a Development of young stems severely stunted; basal internodes on all sides with perforating shoots ± one-sided spongy, swollen and bent. Inserted leaves at the sites of infestation deformed to various extents. E. canadensis: Ditylenchus dipsaci
11b Basal shoot stem with rugose embossments; one larva inside. E. acris: Cause unknown – ? beetle
12a Malformations of single or several capitula => 13
12b Fruit aborted, larva bright yellow. E. acris: Cause unknown – ? gall midge
13a Malformation of single capitula by gall midge larvae => 15
13b Malformation of inflorescence extended over several capitula => 14
14a Capitula deformed, ± sprouting and abnormally pubescent. E. annuus: Cause unknown – ? gall mite
14b Capitula stunted, small, only opening a little. Flowers ± withered, ovaries malformed, styles often elongated and discoloured violet. E. acris, uniflorus: Aceria puculosa
15a Galls caused by gall midges => 16
15b Receptacles swollen, tephritid inducers. Chiliadenus glutinosus: Myopites jasoniae
16a Terminal capitula basally slightly swollen, often remaining closed. Larvae red, non-jumping. E. acris: Dasineura socialis
16b Similar malformations. Heads on shortened stalks, shrivelled, hardened and dying off prematurely. Larvae yellow, jumping. E. acris: Contarinia erigeronis
Laatste bewerking 24.iii.2020
Dichotomous table for gallers on Galeopsis
1a On plant parts above ground => 3
1b On roots => 2
2a Roots with nodular swellings. G. tetrahit: Meloidogyne hapla
2b Roots unaltered externally; inside with giant cells. The bodies of developing female eelworms break through the host tissue and are attached to the root as at first white, then yellowish, eventually partially brown, about poppy-seed sized cysts. G. tetrahit: Heterodera schachtii
3a Galls at tip of vegetative or generative shoots => 11
3b Galls on shoot axis, leaves or flowers => 4
4a Malformations of vegetative organs => 5
4b Flower buds globular, swollen and discoloured, unopened. Containing a white or pale reddish-yellow larva. G. bifida, ladanum, tetrahit: Dasineura tetrahit
5a Galls on leaves distant from shoot tip => 7
5b Galls on axial parts of stem => 6
6a Oblong swelling of upper parts of shoot axis. Shoot tip above swelling usually soon withered. Pith containing many larvae. G. ladanum: Thamnurgus kaltenbachii
6b Conspicuous, usually pale green swelling of basal axial parts; tissue spongy; plant severely stunted. On stems, infected after ± completed longitudinal growth and also on higher situated parts, develop variously shaped galls, on one or all sides, often associated with distortions, ± reddened, spongy. Such galls develop ± locally also on petioles and leaf blades. Galeopsis spp.: Ditylenchus dipsaci
7a Downward roll and distortion of leaves caused by aphids => 8
7b Basal leaf blades with many small, multicellular, wart-shaped, yellowish translucent warts; infestation also encroaching into petioles and stems. G. tetrahit: Synchytrium aureum
8a Aphids up to 2 mm long, dark green, with black siphunculi => 10
8b Aphids yellowish-white or yellow to pale green, or yellow-green with same-coloured siphunculi => 9
10a Cauda and siphunculi of the 1.5–2 mm long aphid black, antennae slightly longer than half the body length. Siphunculi and cauda almost of same length. Galeopsis spp.: Aphis frangulae subsp. beccabungae
10b Cauda of the up to 2 mm long aphid green, lighter than siphunculi. Antennae half the body length. Siphunculi twice as long as cauda. Galeopsis spp.: Aphis gossypii
11a Malformations caused by aphids or spittlebugs => 14
11b Galls caused by gall midges, eelworms or gall mites => 12
12a Galls lacking abnormal pubescence => 13
12b Leaves, also flower buds, stunted, clustered on shoot tips; densely pubescent. G. ladanum: Unidentified gall mite
13a Upper leaf pair of shoot tip substantially undeveloped, erect, ± rolled together with the margins, curled. Petiole and leaf blade base markedly stunted, thickened and discoloured with several midge larvae in between. Soon shrivelling after departure of larva, e.g. G. segetum, tetrahit: Macrolabis sp.
13b Stem below inflorescence, also midrib, shortened, spongy, swollen, sometimes severely distorted, ± reddened. Galeopsis spp.: Ditylenchus dipsaci
Laatste bewerking 11.iv.2020
Dichotomous table for gallers on Pinus
1a On above-ground parts => 2
1b Roots of seedlings distinctly shortened, with nodular swellings or proliferations. Bark loose around central cylinder with eelworms in between. Parts above ground shrivelled. P. sylvestris: Unidentified root eelworm
2a On shoots or needles => 4
2b On cones => 3
3a Cones shrivelled, bent, stone hard, not opening, always ± acuminate. Irregular tunnels in scale bases; already dropping 8–10. Usually a single, sometimes 2 or 3 larvae. P. cembra, mugo, nigra, pinea, ponderosa, sylvestris: Pissodes validirostris
3b One-sided curved cones, with resin and frass, containing caterpillars. P. nigra, sylvestris: Cydia conicolana
3c Cone scales inside with elongated wart-like swellings. P. sylvestris, strobus: Kaltenbachiola strobi
3d Blister-like swellings on cone scales caused by spermogonia and aecia of rust. P. densiflora, sylvestris, virginiana: Cronartium quercuum
4a On shoot axial parts => 7
4b On needles => 5
5a Needles swollen at base => 6
5b Needles accumulated terminally on young shoots, development stunted, undulately curved or bent screw-like, not thickened. Pinus spp.: Pineus pini
5c Fungus. Both surfaces of needles with cylindrical projections of aecia, 1–5 mm long; spermogonia present. Pinus spp.: Coleosporium tussilaginis
6a Infestation of developing needles. They are severely shortened, their bases ± fused over a length of 2–3 mm, swollen, sometimes slightly twisted, erect and in autumn often golden-yellow. Larvae 2–3.5 mm long, orange-reddish to red, lacking sternal spatula; one or occasionally more larvae per gall. P. halepensis, mugo & subsp. rotundata, nigra, pinaster, pinea, sylvestris: Thecodiplosis brachyntera
= The pine needle buckling gall midge Contarinia baeri causes needles constricted at base and bend like walking sticks, dropping already in autumn
6b Needles remain linked, with yellowish, bulging thickenings, shortened, often ± twisted screw-like; a basal, expanded, bag-like widening containing a whitish to yellow beetle larva. P. sylvestris, uncinata: Brachonyx pineti
7a On stems, older branches or several year old twig => 10
7b On young shoots => 8
8a Galls caused by animals => 9
8b Bark of young twigs usually with narrow erupting pads on one side 10–30 mm long, with dusting of reddish-yellow spores. Shoots stunted at infestation site, continuing to grow on healthy side and so deflected. Terminal parts become erect subsequently making s-shaped curves. Pinus spp.: Melampsora populnea
9a Axis gaping over a length of about 20–30 mm, ± swollen. Primary bark and resin channels enlarged; secondary bark and wood slightly thickened. Pith cavity containing a large-headed, yellow- to yellow-brown caterpillar. Open gall often covered with resin mass on one side. P. banksiana, mugo, pinaster, sylvestris: Retinia resinella
= The gall midge Cecidomyia sarae has been recorded from resin lumps and wounds caused by R. resinella
= Two more gall midges, Cecidomyia pini and C. harrisi, occur also in resin exudates of shoots and green cones of P. pinaster, sylvestris without causing malformations. The species differ in larval characters, viz., spatula, dorsal lobes on abdomen
9b Caterpillars at first in lower pith of young, stunted shoot tips or buds, sometimes thickened on one side, crooked, later on dehiscing. Pinus spp.: Rhyacionia buoliana
= the larvae of several leafrollers live as borers in the buds and young shoots of pine trees, causing rather similar damage symptoms. Of the more rare species the biology is not known in sufficient detail to enable discrimination, but at least the equally frequent Pseudococcyx turionella should be considered as a potential causer. The larva of Rh. buoliana bores a tunnel from the base of a shoot upwards; this causes the shoot to bend (“posthorn shoot”); when this happens to the main shoot this causes a permanent bend in the trunk later. The larva of P. turionella empties a terminal bud, then burrows for a short distance downwards. Lateral buds around the dead terminal bud then get the opportunity to develop into shoots, causing a splaying or forking of the branch
9c Young shoot curved and distorted, growth stunted. P. peuce, sibirica, strobus, sylvestris: Pineus strobi
10a Stems or branches with nodular swellings or with proliferations, excessive branching or witches’ brooms => 13
10b Bark of thinner plant parts usually swollen on all sides, several cm long, later on with many, pale yellow blister-shaped swellings, about pea-size, from which yellow fungus spores escape after eruption => 11
11a On P. mugo, sylvestris and other pines with paired needles => 12
11b On P. strobus and other 5-needle whorled pines: Cronartium ribicola
12a Fungus host alternating. Aecia conspicuous, often many on 10–20 cm long swellings of twigs. Galls at thickest part sometimes with twice the normal diameter. Fewer on stems and young trees than on branches. Cronartium flaccidum
= Blister-like swellings on bark caused by spermogonia and aecia of rust. P. sylvestris: Cronartium quercuum
12b Fungus not host alternating; it develops haploid aecia in its sori, which are only able to infect Pinus. Galls as for pine blister rust. P.sylvestris: Endocronartium pini
13a Malformation of complete shoots or witches’ brooms => 16
13b Nodule-, tuber- or spindle-shaped malformations => 14
15a Smaller, up to about 15 (30) mm globular, cancer-like compact nodules on the thicker twigs of P. cembra. “Twig tuberculosis”. Cause unknown – ? bacterium
15b On younger, thin twigs oblong to rotund, at first glabrous, later on rugose, up to 20 (25) mm broad and 10 mm high, yellow-brown swellings, permeated by many channels, originating from proliferation of the bark and persisting for several years. P. mugo, nigra, strobus, sylvestris: Trisetacus pini
16a Slightly extended malformation of complete shoots; proliferation and accumulation of buds. “Budding witches’ broom”. P. cembra, mugo: Trisetacus cembrae
16b Usually voluminous, loose, expanded or smaller, almost globular compact witches’ brooms, especially on P. sylvestris, as well as on some cultivated foreign pines: Inducer unknown
Laatste bewerking 22.iii.2020
Dichotomous table for gallers on Pastinaca
1a On parts above ground => 3
1b On root or root collar => 2
3a On all parts of flowering or fruiting inflorescence => 14
3b On vegetative parts => 4
4a Malformations mainly on the leaf blades of leaflets or leaf sheaths => 8
4b Galls on stems, petioles and midrib or mainly on venation of leaflets => 5
5a Causers live inside galls => 7
5b Causers on galls or fruiting on surface => 6
6a Midrib of rosette leaves of young plants with smaller, or more expanded, sometimes arched, bulging, sometimes reddened swellings, which contain one or several scale insects in depressions on surface. P. sativa: Planchonia arabidis
6b Conspicuous yellow swellings, soon bearing spermogonia and aecia. P. sativa: Uromyces lineolatus
7a pindle-shaped, compact, glabrous, bulging swellings on axial parts. P. sativa: Protomyces macrosporus
7b Petiole often severely stunted, especially spongy at base. Surface wrinkled, sometimes with longitudinal fissures. Infected venation of leaflets ± swollen especially at base of leaf blade, leaf blade curled. P. sativa: Ditylenchus dipsaci
8a Malformation of leaflet leaf blade caused by midge larvae, aphids or cercopids => 9
8b Sheaths of younger leaves ± strongly swollen, slightly thickened. Buds ± stunted. Larvae red. P. sativa: Unidentified gall midge
9a The disfigured leaf blades show slight folds open on upper side or are mainly deflected downwards, caused by aphids or cercopids => 10
9b Depending on stage of development during infestation, the halves of leaflets remain partially or completely folded upwards; main venation ± swollen. Containing several white larvae. P. sativa: Macrolabis heraclei
10a Malformations caused by aphids => 11
10b Leaf midrib shortened and curved, the accumulated leaflets deflected, curled, locally deep green. P. sativa: Philaenus spumarius
10c Leaf, or several leaves, folded, curled or crumpled, often yellowish, with leaf blade and veins ± thickened; containing flattened froth-covered nymphs. P. sativa: Trioza apicalis
11a Aphids ± green => 12
11b Aphids black; leaflets deflected. Leaf blade weakly swollen. P. sativa: Aphis fabae
12a Leaflets rolled inwards and downwards => 13
12b Tips of leaflets strongly curled, at first with small folds, open on upperside; aphids inhabiting the weakly swollen leaf sheaths later on and disfiguring young side shoots as well as umbels. P. sativa: Hyadaphis foeniculi
13a Leaflets deflected downwards, partially curled. Aphid 1.8–2.8 mm long, yellowish-green. Siphunculi slightly club-shaped and pale, almost three times as long as the same coloured cauda, which has at its base a finger-like appendage. P. sativa: Cavariella pastinacae
13b Similar minor malformations. P. sativa: Cavariella theobaldi
13c Leaflets rolled downwards. Aphid lacking tail-like appendage at base of cauda. P. sativa: Semiaphis pastinacae
14a On fruits => 19
14b On inflorescences or flowers => 15
15a Malformation mainly of complete inflorescence or inflorescence stalk => 16
15b Flowers swollen, unopened; inflorescence often ball-like. White larvae inside flower. P. sativa: Contarinia sp.
16a Galls locally on stalks of inflorescence => 18
16b Variable malformations of complete inflorescence => 17
17a Caused by aphids. P. sativa: Hyadaphis foeniculi
17b Ball-like malformations of inflorescence associated with greening on P. sativa, further growth of flowers and stronger pubescence caused by an unidentified gall mite
17c Strong clustering of inflorescence caused by maggots. P. sativa: Cause unknown – ? dipteran
18a Centre of umbel or stalk of umbel ± swollen, club-shaped. Inner wall covered with mycelium. Containing a red larva. P. sativa: Lasioptera carophila
18b Stalk of partial umbel with club-like swelling at base. P. sativa: Unidentified gall midge
19a Fruit slightly swollen; seed aborted; containing a yellow, jumping larva. P. sativa: Contarinia pastinacae
19b Fruit strongly inflated, bladder-like; galls ± reddened, protruding above the umbel; 1 (3) orange-red larvae. P. sativa: Kiefferia pericarpiicola
Laatste bewerking 21.iii.2020
Dichotomous table for gallers on Daucus
1a On above-ground parts => 3
1b On root or root collar => 2
2a Side roots with nodular swellings, a few mm long, partially bearing adventitious roots. D. carota, sativus: Meloidogyne hapla
= A host-specific cyst eelworm, Heterodera carotae with lemon-shaped white or brown cysts on Daucus has been recorded
= Small solid swellings, often curved or twisted, at the tips of side roots, either the needle eelworm Longidorus sp. or dagger eelworm Xiphinema sp. Both are important vectors of viruses
2b The ± green root head thickened, torn open, later on dark-brown. Stalks of leaf tuft spongy, swollen at base, pale. Stem sometimes twisted and undulate with ± equally distributed, rugose pale-green, bulges on surface. D. carota: Ditylenchus dipsaci
3a On inflorescences, flowers and fruits => 13
3b On leaves and stems => 4
4a Large parts of leaves and often several whole leaves curled => 7
4b Leaves or stems with locally wart- or bulge-shaped swellings. Fungus galls => 5
5a Galls remain closed, compact => 6
5b Bulges on petioles, -midrib or on the tips of leaf blades, elongate spindle- to irregular cushion-shaped, ± yellowish to reddish, bearing aecia and spermogonia. D. carota & subsp. maximus, muricatus: Uromyces lineolatus
6a Galls smaller than 1 mm, wart-shaped, inside a ± golden-yellow translucent fungus containing nutritive cells. D. carota: Synchytrium aureum
6b Bulges compact, vitreous, pale green, glabrous, spindle-shaped, only a few mm or up to 15 mm long, depending on infected organ. Many spores close to vascular bundle. D. carota: Protomyces macrosporus
7a Various malformations caused by aphids; usually not species-specific => 9
7b Malformations caused by psyllids or cercopids => 8
8a Leaf midrib and side stems curved, deflected, forming a loose nest of ± curled leaflets. Usually only a few leaves disfigured. D. carota & subsp. sativus: Philaenus spumarius
8b Leaf tip downwardly deflected, upwardly ± swollen, tuberculate, not discoloured. Froth-covered nymphs usually on many strongly curled and stunted leaves. D. carota & subsp. sativus: Trioza apicalis
9a phids green in various gradations => 10
9b Aphids black. Leaf blades weakly curled and deflected. D. carota & subsp. sativus: Aphis fabae
10a Siphunculi distinctly longer than cauda => 11
10b Siphunculi very short on pale green, slightly powdered aphid. Rosette leaves usually strongly curled and densely converging, nest-like, sometimes partially reddened. D. carota & subsp. maximus + sativus: Semiaphis dauci
11a Siphunculi and cauda dark. Antennae as long as half the body length or longer => 12
11b Siphunculi and cauda in wingless aphids pale green translucent. Antennae shorter than half the body length. Aphid pale green, wax absent, distinguished by a finger-shaped tubercle above the cauda. Malformation of leaf much looser than in previous species; slightly discoloured. D. carota & subspp. maximus + sativus: Cavariella aegopodii
12a Aphid up to 2 mm long, yellowish- or greenish-white, posterior with black transverse ligatures. Plant severely stunted, partially with basally inserted severely disfigured inflorescences over all parts. Leaves strongly curled. D. carota & subsp. sativus: Dysaphis crataegi
12b Aphid about 2 mm long, greenish, often blackish-brown. Antennae exceeding the middle of body, but sometimes only a third of body length. Siphunculi distinctly club-shaped, black, about as long as the dark cauda. Usually on ± curled to the stem attached leaves as well as on inflorescence. D. carota & subsp. sativus: Hyadaphis passerinii
13a Complete or partial malformation of inflorescence => 14
13b Fruits swollen, bladder-like, protruding above the umbel. Wall thickened, usually glabrous, the outside often violet-coloured. Containing 1 (‒ 3) orange-red larvae. D. carota & subsp sativus: Kiefferia pericarpiicola
= From similar fruit galls on several umbellifers has been reared Amerapha gracilis, an inquiline of Kiefferia. Another, very rare, inquiline is Trotteria umbelliferarum.
14a Malformations involving many parts of inflorescence => 15
14b Centre of stalk of (partial) umbel swollen, club-shaped to globular. Galls single or multi-chambered; wall tough, covered with whitish-grey mycelium inside. Each chamber contains a red larva. D. carota & subsp. sativus: Lasioptera carophila
15a Inflorescence disfigured by aphids in a very irregular manner. Stalks of partial umbels ± stunted; flowers stunted; developed petals sometimes ± greened or reddened D. carota & subspp. maximus + sativus: Semiaphis dauci
15b Inflorescence usually less stunted; flowers leafy, partially developing new umbels. D. carota & subsp. sativus: Aceria carvi
Laatste bewerking 20.iii.2020
Dichotomous table for gallers on Beta
1a On parts above ground of young plants or on leaves => 8
1b On roots or on beet => 2
= The occurrence of Rhodococcus fascians has been recorded on sugar beet. This bacterium causes the formation of “leafy galls”.
2a On beet => 4
2b On side roots => 3
3a Roots often with many nodular, barrel- or spindle-shaped swellings, usually not exceeding 3–4 mm long, sometimes joining and usually developing side roots. Causer inside gall. B. vulgaris: Meloidogyne hapla
3b All parts of plant severely disfigured. Development of roots stunted, their tips pale yellowish-white, thickened and ± crooked. B. vulgaris: Paralongidorus maximus
3c Similar swellings on root tips. B. vulgaris: Pratylenchus pratensis
3d Roots from the outside not or only slightly swollen; inside with giant cells. Females rupturing from rind, temporarily attached to the root with whitish, later on brown, about poppy seed-size, lemon-shaped egg capsules. Beet corpus usually remaining thin, often densely covered with side roots, so called “hunger roots”. Plant disfigured. B. vulgaris: Heterodera schachtii
4a Root body with ± conspicuous proliferations => 5
4b Young beet gall-like thickened, usually densely provided with adventitious roots. Contains a single larva. B. vulgaris: Bothynoderes affinis
5a Proliferations only rarely exceeding 10 mm => 7
5b Swellings in full-grown condition at least partially much larger than 10 mm => 6
6a Proliferations succulent, with uniform tissue, laterally attached to the upper part of the beet, of variable size ranging from hazelnut to child head; surface glabrous, rarely partitioned into smaller, 4–10 mm thick, usually rotund, deep compartmented single protuberances. Older galls ± browned. B. vulgaris: Agrobacterium tumefaciens
6b Smaller or more expanded, bean-, rarely also fist-sized proliferations, sometimes basally ± constricted, cancer-like, with cavities inside. At first ± orange-coloured, later on browned and with cracked surface. Usually on upper part of beet, sometimes apically elongated. “Beet cancer”. On B. vulgaris: Physoderma leproides
7a Upper part of sometimes many-headed beet body with scab- to cancer-like, cracked parts, which show ± concentric rings in cross-section; skin often detached; underlying tissue spongy, swollen, contains eelworms. B. vulgaris: Ditylenchus dipsaci
= In many aspects a similar, very variable infestation pattern is caused by the proteobacterium Actinomyces scabies; the proliferations usually develop in girdle-shaped arrangements of parasite-free, soon browned, dead, uniform cell complexes which are not true galls. The apically neighbouring area is often depressed and locally replenished with scabby remains of tissue.
7b Up to 10 mm high and about 10–30 mm broad, cracked surface, single or sometimes joined into groups mainly on upper beet part. B. vulgaris: Xanthomonas beticola
8a On larger leaves without distinct involvement of venation => 9
8b Axial parts of shoot, as well as stalks, midrib and lower parts of ± stunted juvenile- or rosette leaves stunted and spongy, swollen. Galls very variable in position and size, pale green, ± wrinkled on surface. B. vulgaris: Ditylenchus dipsaci
9a Malformations caused by fungi which fruit at surface => 14
9b Malformations caused by animals or fungi which fruit inside the gall => 10
10a Leaf blade curled or rolled by animal causers => 11
10b Leaves of young plants, especially basal part of leaf blade, often with many rotund or oblong glabrous galls, pad- or bulge-like, at surface. Leaf blades often stunted, narrowed, pale green, also the margins ± curled. Galls soon decaying. B. vulgaris: Physoderma leproides
11a Leaf blade curls caused by aphids, plant bugs or thrips => 12
11b Leaf blade usually obliquely folded downwards, also over the tip, ± nest-like or with strong, loose rolling. Strongly curled and deep green close to the froth-covered nymph on the underside. B. vulgaris: Philaenus spumarius
12a Malformations caused by aphids => 13
12b Petiole and leaf venation curved upwards, thickened and brittle; leaf blades strongly curled; inner rosette leaves if strongly infected often ± clustered-like head of lettuce. Caused by the virus Savoia betae and transmitted by the bug Parapiesma quadratum
13a Aphids black; often in large colonies on leaf underside. Leaf blades of basal- or stem leaves bent downwards and curled to a great extent. B. vulgaris: Aphis fabae
13b Aphid green. Leaf blade primarily slightly curled. B. vulgaris: Myzus persicae
14a Young leaves stunted, often shorter stalked; several in centre of rosette diseased, ± fleshy thickened, brittle; leaf margin rolled downwards and strongly curled, on underside soon covered with a woolly, dirty violet down of forked conidiophores. B. vulgaris: Peronospora farinosa
14b Leaf blades with rotund, slightly depressed yellowish pads on upper side, bulging on underside, bearing pale yellow aecia on underside, and honey-yellow spermogonia on upper side. Sori on veins or stalks often oblong spindle-shaped. B. vulgaris: Uromyces beticola
14c On various above ground, ± swollen parts of Beta species may occur the often densely grouped, whitish spermogonia and aecia of Puccinia isiacae
Laatste bewerking 7.vii.2020
Dichotomous table for gallers on Inula
1a On above-ground or subterranean shoot parts => 2
1b Roots with many small tuberous swellings. I. brittannica: Meloidogyne hapla
1c Unilocular, round, lignified gall, up to 3 mm in diameter. The young gall is green, later it turns yellow to brown. Pupation, after hibernation, in the gall. I. hirta: Isocolus brunneus
2a On capitula => 15
2b On vegetative plant parts => 3
3a On single, or several, usually disfigured terminal leaves => 12
3b On stems, shoot tips; malformations sometimes extending into isolated leaves => 4
4a On shoot tips or lateral buds => 5
4b Smooth soft-walled globular gall, about 5 mm across, yellow-green to red, on various places on stem, leaf buds and flower heads; sometimes several clustered together or connate. One chamber with one larva. Dittrichia viscosa; Inula britannica, conyzae, ensifolia, oculus-christi, salicina: Acodiplosis inulae
4c Spindle-shaped green gall (20 x 10 mm), sometimes spherical; large cavity containing a milk-white larva. Adults emerge in end May. Limbarda crithmoides: Euarestella megacephala
4d Spindle-shaped galls on stem base and in stems, contain frass: Unidentified lepidopteran
4e Unilocular, round, lignified gall, up to 3 mm in diameter. The young gall is green, later it turns yellow to brown. Pupation, after hibernation, in the gall. I. hirta: Isocolus brunneus
5a Malformations of above-ground buds or shoot tips => 6
5b The subterranean buds, and, sometimes also basal above-ground buds on root collar transformed to one-chambered solitary or clustered galls, up to 5 mm long, tough-walled, fleshy; the outside with dense, long, initially white, later grey-brown felt-like hairs. One reddish larva. I. britannica, ensifolia, germanica, hirta, hybrida, salicina: Inulomyia subterranea
6a Terminal- or lateral artichoke-like buds, malformations remaining closed => 7
6b Terminal buds or buds on stems, sometimes involving the neighbouring leaves, transformed into a one-chambered dry-fleshy closed gall about 5 mm across. Containing a single larva. Dittrichia viscosa; Inula britannica, conyzae, ensifolia, oculus-christi, salicina: Acodiplosis inulae
7a Rosette-like malformations => 11
7b More or less bud-like malformations => 8
8a Galls not exceeding 10 mm => 9
8b Partly open bud or young leaves, usually of basal rosette, are largely stunted and densely haired over an extensive area; containing yellow-orange larvae. I. conyzae: Neomikiella beckiana
9a Glabrous or pubescent galls caused by midge larvae => 10
9b Leaves at the shoot tip stunted, curled. In the middle bud-like converging; the following leaves slightly increasing in size and ± rosette-like spreading. I. salicina: Unidentified gall mite
10a Galls conspicuously pubescent => 11
10b Galls inconspicuously pubescent. Young leaves terminally ± severely stunted, at least the basal parts pale and rolled together composing a slender, erect artichoke, enclosing the youngest parts. Containing whitish to yellow larvae. I. britannica, hirta, salicina: Contarinia inulicola
= In galls on terminal shoots, or lateral buds, of various Inula species from dry habitats live gall midges belonging to a second species group, which may differ from the species on I. britannica.
11a Gall about 4–10 mm long, sometimes enclosed by a few shortened leaves, basally thickened and widened, with their leaf blade ± spreading => 13
11b Gall ± distinctly bud-like, about 8–18 (20) mm long; the exterior leaves decreasingly stunted, the base conspicuously enlarged and variously disfigured, strongly white pubescent over large areas. Larva yellowish-red. I. conyzae: Neomikiella beckiana
12a Malformations caused by aphids or cercopids, always lacking dense pubescence => 13
12b Leaves on the shoot tip ± tightly rolled or folded together, densely pubescent and partially stunted. I. salicina, Dittrichia viscosa: Eriophyes cupulariae
13a Aphid galls => 14
13b Leaf blades downward arched and strongly curled, dark green close to the froth-covered nymph. I. britannica, helenium: Philaenus spumarius
14a Leaf blade disfigured, deflected, yellow-spotted, with disfigured venation. Dittrichia viscosa, I. conyzae, helenium: Brachycaudus helichrysi
14b Leaf blade with loose upward marginal roll, sometimes narrowly pod-like malformation on young leaf blades. I. ensifolia, hirta, salicina: Brachycaudus salicinae
15a Larvae rotund-cylindrical usually living, in the soon ± hardened, upwardly arched receptacle. Tephritid gall causers => 16
15b More or less expanded parts of the receptacle of younger, strongly transformed capitula almost semiglobular. Galls about 4–5 mm long with soft fleshy wall containing an elongate midge larva. Dittrichia viscosa; Inula britannica, conyzae, ensifolia, oculus-christi, salicina: Acodiplosis inulae
15c Midge larvae develop in flower heads. I. salicina: Jaapiella inulicola
15d Unilocular, round, lignified gall, up to 3 mm in diameter. The young gall is green, later it turns yellow to brown. Pupation, after hibernation, in the gall. I. hirta: Isocolus brunneus
16a Separate galls with tough, later woody wall; mostly with several in a flower head and bulging out from the receptacle => 17
16b Receptacle sometimes thickened on one side. Galls tough-walled when mature, but not woody. I. britannica, ensifolia, hirta, oculus-christi: Inuromaesa maura
16c Inducer of hardened receptacle galls on I. britannica, conyzae: Trupanea stellata
17a Receptacle inside the flower head strongly swollen, bulge-like to conical disfiguration, apically eventually having an emergence hole. One larva per chamber. I. ensifolia hirta, hybrida, salicina, Limbarda crithmoides: Myopites eximia and/or M. longirostris
17b Similar galls on I. britannica: Myopites tenellus and/or Inuromaesa maura
17c On Dittrichia viscosa. Receptacle swollen, transformed into a woody multilocular gall, red-brown, rotund or elongated, glabrous, measuring 4–8 mm with apically 2–4 (5–6) paler coloured appendages representing the achenes. Each larval chamber containing a white-yellowish larva: Myopites limbardae and/or M. olivieri
17d On Dittrichia viscosa. The receptaculum is transformed into a smooth sphere; a few galled achenes, crowned by pappus hairs emerge as narrow cones from the gall; the other achenes are aborted and are arranged around the gall: Myopites stylatus
= Myopites inulaedysentericae, occasionally recorded from Inula species
= Furthermore from flower heads have been recorded the tephritid flies Ictericodes zelleri from I. conyzae, and Acinia biflexa from I. brittanica
Laatste bewerking 18.iii.2020
Dichotomous table for gallers on Capsella
1a On parts above ground => 5
1b On root collar or on roots => 2
2a On roots => 3
2b Root collar with rotund, 5–7 mm long, succulent, one-chambered gall. Containing a single larva. C. bursa-pastoris: Ceutorhynchus assimilis
3a Outside of roots hardly changed or with small, ± nodular swellings => 4
3b Conspicuous, succulent, spindle-shaped to expanded barrel-shaped, compact swellings of variable size on main- and side roots. C. bursa-pastoris: Plasmodiophora brassicae
4a Side roots with small, nodule- or spindle-shaped swellings. C. bursa-pastoris: Meloidogyne hapla
4b Outside of roots not noticeably changed; giant cells inside; temporarily with at first white, later on partially browned lemon-shaped cysts, about poppy seed size. C. bursa-pastoris: Heterodera cruciferae and/or H. schachtii
5a Galls on various parts caused by fungi sporulating at surface => 18
5b Malformations caused by animals => 6
6a Malformation of ± extensive parts caused by aphids or spittlebugs => 10
6b Galls caused by other parasites => 7
7a On stems or leaf midrib => 8
7b Phyllanthy, flowers greened or leafy; infestation encroaching also on vegetative parts. Stalk of inflorescence stunted; leaves stunted, ± rolled inwards and twisted. All diseased parts densely pubescent, hairs branched and 3–4 times longer than the normal ones. C. bursa-pastoris: Aceria drabae
7c Swollen flower bud, preventing development of fruits; each attacked flower bud with 1‒3 larvae; pupation in soil, more generations. Capsella bursa-pastoris: Gephyraulus capsellae
7d Young siliques slightly disfigured. Contain several (1) 3 (6) white larvae. C. bursa-pastoris: Dasineura napi
= The gall midge Contarinia nasturtii has been reported from on C. bursa-pastoris.
8a Inducers inside the galls => 9
8b Stem spindle-shaped to irregularly bulging; rind with rotund-oval, sometimes rimmed depressions containing a froth-covered nymph of the polyphagous inducer. C. bursa-pastoris: Planchonia arabidis
9a Spindle-shaped glabrous galls, 10–40 mm long swellings or oblong-oval, flattened, compact, at first succulent, also deep green inside, on petioles and leaf veins. Containing a single, curved larva. C. bursa-pastoris: Ceutorhynchus chalybaeus
9b Stems of young plants severely stunted and spongy thickened; leaves stunted; especially basal parts swollen; infestation of older plants results in ± expanded, local, sometimes strongly curved swellings on stems and leaves. Gall always pale green, brittle, ± wrinkled at surface. C. bursa-pastoris: Ditylenchus dipsaci
10a Malformations caused by aphids => 11
10b Inflorescence stunted, flowers of sometimes one-sided curved midrib clustered, ± stunted. With a froth-covered nymph. C. bursa-pastoris: Philaenus spumarius
11a Malformations of various shape and expansion; atypical for this causer. Aphid green => 12
11b Shoot tips ± stunted; leaves, and flowers clustered; leaf blades deflected, slightly curled. Flowers disfigured, ± greened. Aphids black. C. bursa-pastoris: Aphis fabae and/or Aphis fabae subsp. evonymi
12a Malformations usually restricted to some parts terminally on shoots or on leaves => 13
12b Infected young plants with severely stunted shoots, leaves rolled inwards and curled; plant often completely disfigured. Axis of inflorescence and flower peduncles shortened, ± curved. Flower parts stunted and disfigured, ± discoloured, also greened or violet; siliques disfigured, bent. Aphid 1.5–2 mm, grey-green to grey-yellowish, antennae half the body length, siphunculi yellow, cauda oblong, pale greenish. C. bursa-pastoris: Lipaphis erysimi
13a Aphid not covered with wax powder => 14
13b Aphid 2–2.5 mm long, yellowish–green, with two longitudinal rows of small cross stripes, densely white powdered C. bursa-pastoris: Brevicoryne brassicae
14a Aphid yellow to green => 15
14b Aphid dark green, up to 2 mm long, antennae half the body length. Siphunculi black, cauda oblong, pale green to yellowish-white. C. bursa-pastoris: Aphis gossypii
15a Aphid yellow to greenish-yellow or pale green => 16
15b Aphid green; siphunculi black, cauda oblong, brown. C. bursa-pastoris: Aphis gossypii subsp. capsellae
16a Cauda of aphid oblong => 17
16b Cauda short, broad and rounded. Aphid hardly 2 mm long, greenish to yellowish; mainly on basal leaves on slightly rolled leaves. C. bursa-pastoris: Brachycaudus cardui subsp. lateralis
17a Antennae of the about 2–3 mm long aphid longer than the mainly yellowish-green to straw-coloured body, darker green at the insertion of siphunculi; these yellow to orange-coloured, with blackish tip. Leaves weakly rolled downwards or curved and slightly arched. C. bursa-pastoris: Aulacorthum solani
17b Antennae of the about 1–1.5 mm long, yellowish to pale green aphid surpassing the anterior half of the body, siphunculi and cauda same colour as body. Inflorescence stunted, bearing more densely clustered flowers. Leaves ± downwards deflected, sometimes bulging. C. bursa-pastoris: Aphis nasturtii
18a Bulge-like, at first closed, glossy, porcelain-like, after rupturing mealy dusting sori of variable size on all green parts. Often causing diverse swellings and distortions. Infestation of flowers results in often conspicuous malformations of ovaries. C. bursa-pastoris: Albugo candida
18b Stem and also axis of inflorescence usually with expanded, conspicuous, often distorted swellings, soon covered with a down of branched conidiophores. Flowers of diseased inflorescences severely stunted. Leaves of axillary shoots if infected early, ± spoon-like arched, thickened, brittle, pale green; with a dense down of conidiophores on underside. C. bursa-pastoris: Hyaloperonospora parasitica
18c Leaf with hard gregarious pustules, less than 0.5 mm across; contain fungi. C. bursa-pastoris: Synchytrium aureum
Laatste bewerking 18.iii.2020
Dichotomous table for gallers on Poa
1a On above-ground parts => 3
1b On roots => 2
2a Roots with several curved swellings, about 0.5-6 mm long, crooked or half screw-shaped. Ochlopoa annua, P. pratensis, trivialis: Subanguina radicicola
2b Poppy seed size, white to brown cysts, on outside of roots. Poa spp.: Heterodera avenae
3a Galls on inflorescences or their parts => 19
3b Malformations on vegetative parts => 4
3c Whitish, at surface yellowish or brownish patches, which envelope a large area of the upper part of stem, of which further development is stunted. Node of stem rarely swollen, encircled by fungus stroma, yellowish when mature; several nodes may be affected; flowering stunted; stroma contains narrow asci and filamentous spores. P. nemoralis, pratensis, stiriaca, trivialis: Epichloë typhina
4a Malformations on leaves or localised galls on culms => 6
4b Whole plant disfigured => 5
5a Plant withered all parts especially at base ± spongy, thickened. Ochlopoa annua, Poa trivialis: Ditylenchus dipsaci
5b Plant, especially culm, severely stunted; panicle bleached. Ochlopoa annua: Unidentified dipteran
6a Galls on culm => 10
6b Malformations on leaf blades and sheath => 7
7a Expanded malformations => 8
7b Leaf blade at base with oval or elongated bulge-shaped, usually dark violet swellings several mm long; occasionally occurring on leaf sheaths. P. nemoralis, palustris, pratensis: Anguina sp.
8a Leaf blades, partially also sheaths, with several long, parallel bleached stripes of smut, later on with dusting of spores. Fungus exceptionally also on panicle => 9
8b Leaf blade spirally rolled or twisted. P. nemoralis: Inducer unknown
10a Galls bulge-like or spindle- to club-shaped, glabrous or grooved => 12
10b Galls occupied with many rootlets, up to 10 mm long => 11
11a Stem in the middle or upper part of the culm above a node locally weakly swollen, with many, at first whitish, then pale brown rootlets, in longitudinal direction at either side of furrow, ± appressed to culm, protruding from leaf sheath. Larvae white, between the flattened shoot axis and leaf sheath. P. alpina, cenisia, nemoralis, pratensis, trivialis: Mayetiola graminis
11b Similar galls with development of closely crowded adventitious rootlets mostly on above-ground or subterranean nodes on culm; rootlets however not separated by longitudinal furrow, but irregularly growing in a tangled mass. P. nemoralis: Mayetiola radicifica
12a Less or more distinct spindle-shaped swellings on culm; containing larvae => 16
12b Larvae on culm underneath the often somewhat inflated leaf sheath => 13
13a Larvae in distinct depressions of culm, usually situated above the upper node => 15
13b Shoot axis weakly swollen above the second or third node => 14
14a The basal part of the stem, above the 2nd or 3rd node, is more or less swollen. Between the leaf sheath and the stem live here a variable number of white larvae, each in an oval shallow depression of the stem. Pupation within the gall, in a puparium. Larval spatula present, hastiformous. P. nemoralis, occasionally P. pratensis: Mayetiola joannisi
14b The basal part of the stem is more or less swollen. Larval spatula absent. Furthermore, see Mayetiola joannisi. P. pratensis: Mayetiola schoberi
15a Culm usually above the last node with elongated, one-sided, black-walled depression; containing a single larva. P. pratensis: Hybolasioptera fasciata
15b Culm above the last node with one or several slender, saddle-shaped rimmed depressions. Each containing a brick red larva. P. palustris, pratensis: Haplodiplosis marginata
16a Galls on P. palustris, bulbosa => 18
16b On P. nemoralis => 17
17a Grain-like swellings protruding from the sheaths, spindle-shaped, up to 5 mm long; at first pale green, then brownish, longitudinally grooved. Containing a single white larva: Tetramesa poae
17b Culm distinctly shortened; slightly spindle-shaped thickened above a node below the not spreading sheath; panicle remains covered by sheath. Containing a single larva: Tetramesa sp.
18a On P. palustris; weak, discoloured swelling on the shoot axis above the 3rd, 4th or 5th node: Tetramesa sp.
18b On P. alpina, bulbosa. Swelling up to 18 mm long, 2 mm broad above the first node below the panicle, protruding from the leaf sheath on one side. Tetramesa sp.
20a Ovaries slender, bottle-shaped, enlarged, usually discoloured violet. Ochlopoa annua, Poa alpina, nemoralis, palustris, pratensis: Anguina agrostis
20b Similar galls; glumes sometimes conspicuously elongated. P. alpina, pratensis: Unknown eelworm
20c Infected ears and panicles appear normal. Since the larvae inside the flowers feed on the flowering parts they prevent seed formation. The result is wrinkled seed or sterile ears. P. pratensis: Dasineura poae
21a Spikelets leaf-like, not transformed into bulbils. Flowers thickened at base and ± reddened. P. bulbosa: ? Anguina sp.
21b Spikelets variously disfigured, often withering prematurely, with symptoms of bleaching. Poa spp.: Aceria tenuis and/or Aceria cornuta
Laatste bewerking 16.iii.2020
Dichotomous table for gallers on Dianthus
2a On flower buds and flower