Beta, beet

See also Patellifolia.

Beet miners are described in more detail by Skuhravy ao (1967a).

1amine full depth; larva with chitinised head => 2

1b mine upper- or lower-surface; larva a maggot => 7

1c fleck mine =16

1d galls, etc. => 100

2a mine small, very irregular in shape => 3

2b minw not that small, with a more constant shape => 5

3a larva: pinacula colourless (the bases of the setae themselves are black) : Cnephasia incertana

3b pinacula black => 4

4a larva: behind/below the anus a chitinous comb: Cnephasia asseclana

4b anal comb absent: Cnephasia stephensiana

5a larva without feet: Pseudophytobius acalloides

5b larva with thoracic fewet and prolegs => 6

6a mine in stem or midrib, with offshoots into the leaf: Scrobipalpa ocellatalla

6bmine completely within a leaf : Scrobipalpa nitentella

7alarge whitish blotch without an initial corridor; much blackish-green frass; at the beginning of the first mine (the larvae may leave a mine and start again elsewhere) a group of oval egg shells => 8

7bcorridor, ending or not in a blotch; at most one egg shell at mine begin => 10

8a larva: lowest of the mandibular teeth exceptionally large: Pegomya cunicularia

8blowest tooth not that large (nb: the larva of Pegomya interruptella is not described) => 9

9aangle between terminal and subterminal mandibular teeth almost 90°: Pegomya betae

9bthis angle very sharp: Pegomya hyoscyami

10amine ends in a blotch; frass in grains => 11

10bmine a corridor untill the end; frass in strings => 14

11aat mine begin, at the lower-surface of the leaf an egg shell (may fall off!!) => 12

11bno egg shell => 13

12ainitial corridor with irregular margins and side branches, rather abruptly terminating in a blotch; egg shell tender, not ribbed, easily falling off; anterior spiracle of larva with 5-7 papillae: Psilopa leucostigma

12binitial corridor with smooth margins, gradually widening into a blotch; egg shell fiirm, ribbed, persistent; anterior spiracle of larva with 2 papillae: Clanoneurum cimiciforme

13ablotch with wide offshoots where frass is located in green bands: Scaptomyza graminum

13bfrass scattered regularly, very sparingly, in fine greyish black grains: Amauromyza flavifrons

14acorridor pinnately branched, main branch positioned over the midrib: Liriomyza strigata

14bcorridor not pinnately branched or unbranched, not associated with the midrib => 15

15a corridor usually starts lower-surface, turning upper-surface later; regularly forming a secondary blotch: Liriomyza bryoniae

15b corridor usually starts upper-surface, turning lower-surface later; rarely forming a secondary blotch: Liriomyza huidobrensis

16a case unusually slender; Canary Islands: Coleophora pseudopoecilella

16b case rather squat; Mediterranean Region: Coleophora crepidinella

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 Heteroderidae: Heterodera schachtii, trifolii

101b Meloiogynidae: Meloidogyne artiellia, hapla, naasi

103 – Coleoptera

103a Curculionidae: Bothynoderes affinis

105 – Hemiptera

105a Aphididae: Aphis fabae fabae; Hayhurstia atriplicis

105b Triozidae: ? Trioza chenopodii

107 – rust fungi

107a Pucciniaceae: Puccinia isiacae; Uromyces beticola

109 – powdery and downy mildews

109a Erysiphaceae: Erysiphe betae; Leveillula cylindrospora

109b Peronosporaceae: Peronospora schachtii

110 – other causers

110a Bacteria, Actinomycetales: Rhodococcus fascians

110b Bacteria, Rhizobiales: Agrobacterium tumefaciens

110c Fungi, Mycosphaerellaceae: Ramularia beticola

110d Fungi, Physodermataceae: Physoderma leproides

Not included in the key: Liriomyza trifolii; Scrobipalpa atriplicella.