Thlaspi, penny-cress

Incl. Microthlaspi, Noccaea.

1a fleck mine; larva mines from a helicoidal case: Apterona helicoidella

1b no fleck mine; larva mines from the inside => 2

1c galls, etc => 100

2a larva with well recognisable head; mine full depth => 3

2b larva a maggot; mine largely or entirely upper- or lower-surface => 8

3a larva with thoracic feet => 4

3b larva without feet => 7

4a larva with prolegs; older larvae live free => 5

4b larva, with prolegs, mines all its life: Phyllotreta nemorum

5a free living larvae among spun leaves => 6

5b free living larvae at the underside of the leaf, where they cause window feeding: Plutella xylostella

6a larva: pinacula colourless (the bases of the setae themselves are black): Cnephasia incertana

6b pinacula black: Cnephasia stephensiana

7a mine begins at a gall in the petiole: Ceutorhynchus chalibaeus

7b no gall in the petiole: Ceutorhynchus minutus

8a frass powdery, in green clouds in remote corners of the mine: Scaptomyza flava

8b frass in black grains or strings => 9

9a pupation in the mine, in a, generally lower-surface, pupal chamber: Chromatomyia horticola

9b pupation external => 10

10a pinnately branched corridor, main and side branches on top of midrib and major side veins; corridor nowhere strongly widened: Liriomyza strigata

10b corridor not pinnate, widened in the end to form an elongate blotch on top of the midrib: Liriomyza xanthocera

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 Heeroderidae: Heterodera cruciferae

101c Meloidogynidae: Meloidogyne hapla

103 – Coleoptera

103a Curculionidae: Ceutorhynchus assimilis, carinatus

104 – Diptera

104a Cecidomyiidae: Contarinia nasturtii, thlaspeos

105 – Hemiptera

105a Aphididae: Brevicoryne brassicae; Lipaphis erysimi

107 – rust fungi

107a Pucciniaceae: Puccinia thlaspeos, isiacae

108 – smut fungi

108a Fungi, Glomosporiaceae: Thecaphora thlaspeos

109 – powdery and downy mildews

109a Erysiphaceae: Erysiphe cruciferarum; Leveillula taurica

109b Peronosporaceae: Hyaloperonospora thlaspeos-arvensis, thlaspeos-perfoliati; Peronospora thlaspeos-alpestris

110 – other causers

110a Fungi, Albuginaceae: Albugo candida

110b Fungi, Plasmodiophoraceae: Plasmodiophora brassicae

110c Fungi, Synchytriaceae: Synchytrium infestans

Not included in the key: Liriomyza trifolii.

20/02/2017