Chrysanthemum, corn marigold, ox-eye daisy, marguerite

Incl. Dendranthema, Glebionis, Leucanthemum.

1a fleck mine => 2

1b corridor or blotch mine => 6

1c mine small, of indefinite shape; older larvae live free among spun leaves => 23

1d galls, etc => 100

2a hole in the mine untidy, not neatly circular; case helicoidal: Apterona helicoidella

2b hole precisely circular; case more or less tubular => 3

3a tubular silken case; case yellowish or greyish => 4

3b sheath case; case black => 5

4a mouth angle c. 30°: C. folllicularis

4b mouth angle 45-60°: Coleophora trochilella

5a case with some diagonal ribs: Coleophora caelebipennella

5b case with some transverse ribs, behind the mouth: Coleophora rectilineella

6a mine full depth, transparant; larva with chitinised head => 7

6b mine upper- or lower-surface, opaque; larva a maggot => 11

7a mine begins as a corridor in the leaf base or midrib (after having moved to another location the mine is more blotch-like and not bound to a fixed position); larva without feet: Orthochaetes insignis and setiger

7b initial mine not associated with leaf basis or midrib; larva with thoracic feet => 8

8a inflated blotch with folds, not starting with a gallery: Scrobipalpa chrysanthemella

8b mine, at least in its beginning, a gallery => 9

9a on Leucanthemum pallens, alpine species: Bucculatrix alpina

9b on Leucanthemum vulgare, lowland species => 10

9b the mine of Bucculatrix latviaella is unknown, and its hostplant can only be guessed

10a corridor hair thin form start to end; older larvae live free and cause window feeding: Bucculatrix nigricomella

10b corridor widens considerably; lave mines all its life: Bucculatrix argentisignella

11a secondary feeding lines conspicuous; mine a blotch or a wide corridor => 12

11b no secondary feeding lines apparent => 14

12a elliptic lobed blotch on top of the midrib, with a central black spot (accumulation of frass): Trypeta artemisiae

12b broad gallery, centered over the midrib and lateral veins; frass dispersed, therefore no central black spot => 13

13a side branches of the mine widened towards the leaf margin: Cornutrypeta spinifrons

13b lateral branches distally not widened: Trypeta zoe

14a primary blotch, usually with several larvae; in greenhouses: Amauromyza maculosa

14b corridor, rarely a secondary blotch, with one larva; in greenhouses and outside => 15

15a pinnately branched corridor, positioned over the midrib and secondary veins: Liriomyza strigata

15b mine not pinnate, not associated with the leaf venation => 16

16a pupation in the mine; puparium in a usually lower-surface pupal chamber: Chromatomyia cf. syngenesiae (but see also Ch ciliata and paraciliata)

16b pupation only after the mine has been vacated => 17

17a frass in isolated grains => 18

17b frass in strings => 19

18a frass grains relatively large, widely separated: Phytomyza leucanthemi

18b frass grains small, close together: Phytomyza tanaceti

19a essentially on Achillea ansd Anthemis, but reported from Chrysanthemum coronarium: Liriomyza ptarmicae

19b mainly on greenhouse chrysanthemums* => 20

20a larva: rear spiraculum with 3 papillen => 21

20b larva: rear spiraculum with ≥ 6 papillae => 22

21a corridor densely coiled, almost a secondary blotch: Liriomyza trifolii

21b corridor runs loosely through the lamina: Liriomyza sativae

22a mine usually in the basal half of the leaf, often in contact with the midrib, often between two lateral veins: Liriomyza huidobrensis

22b mine without a preferred position, tresspassing over lateral veins; older parts of the mine often upper-surface: Liriomyza bryoniae

23a larva: pinacula colourless (the bases of the setae themselves are black) : Cnephasia incertana

23b pinacula black => 24

24a larva: behind/below the anus a chitinous comb: Cnephasia asseclana

24b anal comb absent: Cnephasia stephensiana

100a Nematoda => 101

100b Acari => 102

100c Coleoptera => 103

100e Diptera => 104

100f Hemiptera => 105

100d Hymenoptera => 106

100g rust fungi => 107

100h smut fungi => 108

100i powdery and downy mildews => 109

100j other causers => 110

101 – Nematoda

101a Anguinidae: Ditylenchus dipsaci

101b Aphelenchoidae: Aphelenchoides fragariae, ritzemabosi

102 – Acari

102a Eriophyidae: Epitrimerus alinae; Paraphytoptus chrysanthemi

105 – Hemiptera

105a Aphididae: Coloradoa tanacetina; Trama troglodytes

105b Asterolecaniidae: Planchonia arabidis

105c Triozidae: ? Craspedolepta flavipennis; Trioza chrysanthemi

108 – smut fungi

108a Entylomataceae: Entyloma scalianum

109 – powdery and downy mildews

109a Erysiphaceae: Euoidium chrysanthemi; Golovinomyces macrocarpus, orontii; Leveillula taurica

109b Peronosporaceae: Bremia lactucae; Peronospora radii

110 – other causers

110a Bacteria, Actinomycetales: Rhodococcus fascians

110b Bacteria, Rhizobiales: Agrobacterium tumefaciens

110c Fungi, Synchytriaceae: Synchytrium aureum, vulgatum

110d Fungi, Taphrinaceae: Protomycopsis leucanthemi

110e Lepidoptera, Tortricidae: Dichrorampha consortana

* For a definite identification of these four, often very noxious, species a study of the male genitalia, or biochemical techniques are necessary.

Not included in the key: Liriomyza dendranthemae.

pub 29.i.2017 · mod 11.ix.2017