1a larva with well recognisable head; mine full depth, transparant => 2

1b larva a maggot; mine upper- or lower-surface, greenish when lighted from behind => 4

1c galls, etc => Tables for all parasites per species

2a larva with prolegs; older larvae live free under the leaf; mine small, roundish: Plutella xylostella

2b no prolegs;larve mines livelong; mine not that small, a corridor => 3

3a larva without feet: Ceutorhynchus minutus

3b larva with thoracic feet: Phyllotreta nemorum

4a frass powdery, in green clouds in remote corners of the mine; mine in the end widened into an irregular blotch: Scaptomyza flava

4b frass black, in grains or strings; mine a corridor till the end => 5

5a corridor closely following the leaf venation => 6

5b corridor independent of the leaf veins => 7

6a larva: cephalic skeleton with three backwards pointing arms: Ophiomyia beckeri

6b cephalic skeleton with two backwards pointing arms: Liriomyza strigata

7a pupaption within the mine, in a, generally lower-surface, pupal chamber: Chromatomyia horticola

7b pupation external => 8

8a larva: rear spiraculum with 7-12 papillae: Liriomyza bryoniae

8b rear spiraculum with 3 papillae: Liriomyza brassicae