Raphanus, radish

fam. Brassicaceae

1a corridor, never widening into a blotch => 2

1b blotch, may be preceded by a corridor => 9

1c galls, etc. => 100

2a corridor ends upon a thick vein; from there the larva continues as a borer => 3

2b corridor not ending upon a vein => 4

3a larva a maggot: Phytomyza rufipes

3b larva with chitinised head: Ceutorhynchus pallidactylus

4a corridor pinnately branched, mian branch overlying the midrib: Liriomyza strigata

4b corridor not pinnately branched, noit associated with the midrib => 5

5a mine full depth; larva with chitinised head => 6

5b mine upper- of lower-surface; larva a maggot => 7

6a mine < 1 cm, larva, with feet, later lives free : Plutella xylostella

6b mine > 1 cm, larva, without feet, remains in the mine until short before pupation: Ceutorhynchus minutus

7a frass in discrete grains; puparium in the mine in a, usually lower-surface, pupal chamber: Chromatomyia horticola

7b frass at least partly in strings; pupation outside the mine => 8

8a larva: rear spiraculum with 3 papillae: Liriomyza brassicae

8b rear spiraculum with 7-12 papillae: Liriomyza bryoniae

9a mine at the leaf basis, associated with the galled petiole: Ceutorhynchus napi

9b petiole not galled => 10

10a mine a blotch over, partly also in, the midrib; initially elliptic, later widening => 11

10b mine not associated with the midrib => 12

11a frass powdery, in blackish-green clouds: Scaptomyza flava

11b frass partly in strings: Liriomyza xanthocera

12a mine < 1 cm; larva, with feet, later lives free: Plutella xylostella

12b mine > 1 cm; larva, without feet, in the mine till shortly before pupation: Phyllotreta nemorum

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

101a Heeroderidae: Heterodera cruciferae

101c Meloidogynidae: Meloidogyne hapla

104 – Diptera

104a Cecidomyiidae: Contarinia nasturtii; Dasineura napi; Gephyraulus raphanistri

105 – Hemiptera

105a Aphididae: Brevicoryne brassicae; Lipaphis erysimi, pseudobrassicae

107 – rust fungi

107a Pucciniaceae: Puccinia isiacae

109 – powdery and downy mildews

109a Erysiphaceae: Erysiphe cruciferarum; Golovinomyces orontii

109b Peronosporaceae: Hyaloperonospora brassicae

110 – other causers

110a Fungi, Albuginaceae: Albugo candida

110b Fungi, Plasmodiophoraceae: Plasmodiophora brassicae

110c Fungi, Synchytriaceae: Synchytrium aureum

Not included in the key: Cnephasia lineata; Liriomyza trifolii.

20/02/2017