Succisa, devils’-bit scabious

fam. Caprifoliaceae

1a mine transparant, full depth, usually a blotch; larva with chitinised head => 2

1b mine upper- or lower-surface, greenish in transparancy, more or less a corridor; larva a maggot => 3

1c galls, etc => 100

2a at the point of oviposition a shining black drop of dried secretion; pupation witihn the mine: Trachys subglaber , possibly also T. troglodytes

2b no such black drop; larva mines from a silken tube: Scythris picaepennis

3a mine not associated with the midrib => 4

3b mine radiation from, or positioned over, the midrib => 6

4a frass allmost absent, or a few big lumps at the end of the mine; puparium formed after the mine has been vacated; often a secondary blotch: Aulagromyza similis

4b frass present, grains, strings etc; puparium formed within the mine => 5

5a corridor long, in the distal half of the leaf; turning the surrounding leaf tissue violet: Chromatomyia succisae

5b corridor shorter; no preferred position; no discolouring of the leaf: Chromatomyia horticola

6a corridors in the leaf blade radiate from the basal half of the midrib: Chromatomyia ramosa

6b corridor pinnately branched, its main axis overlying the midrib: Liriomyza strigata

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 Meloidogynidae: Meloidogyne hapla

102 – Acari

102a Eriophyidae: Leipothix succisae

104 – Diptera

104a Cecidomyiidae: Contarinia dipsacearum

105 – Hemiptera

105a Aphididae: Aphis confusa

105b Triozidae: Trioza munda

107 – rust fungi

107a Pucciniacee: Aecidium succisae

108 – smut fungi

108a Microbotryaceae: Microbotryum flosculorum, succisae

109 – powdery and downy mildews

109a Erysiphaceae: Erysiphe knautiae

109b Peronosporaceae: Peronospora violacea

110 – other causers

110a Fungi, Synchytriaceae: Synchytrium succisae

Not included in the key: Rhopobota stagnana; Trachys troglodytes subglaber.

14/02/2017