Viola, violet

1a mine exclusively in the leaf blade => 2

1b next to the blade also the petiole is mined out => 5

1c galls, etc => 100

2a fleck mine: Apterona elicoidella

2b corridor or blotch => 3

3a frass in strings; branched corridor: Liriomyza strigata

3b frass in fine grains; whitish blotch => 4

4a on Viola palustris: Galiomyza beckeri

4b on V. reichebachiana, riviniana, tricolor: Galiomyza violiphaga

5a larva a maggot: Liriomyza violicaulis

5b larva with feet and chitinised head: Pancalia nodosella

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 Aphelenchoididae: Aphelenchoides fragariae

101c Meloidogynidae: Meloidogyne hapla

105 – Hemiptera

105a Aphididae: Aphis violae

107 – rust fungi

107a Melampsoraceae: Melampsora lapponum

107b Pucciniaceae: Puccinia alpina, cynodontis, fergussonii, ruebelii, violae; Uredo alpestris

108 – smut fungi

108a Urocystidaceae: Urocystis kmetiana, violae

109 – powdery and downy mildews

109a Erysiphaceae: Golovinomyces orontii

109b Peronosporaceae: Peronospora violae

110 – other causers

110a Bacteria, Actinomycetales: Rhodococcus fascians

110b Fungi, Synchytriaceae: Synchytrium alpinum, aureum, globosum, saxifragae

Not included in the key: Orthochaetes setiger.

05/01/2017