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

1b blotch or gallery, larva mines from within => 2

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

2a mine upper- or lower-surface; larva a maggot => 3

2b mine full depth; larva with chitinised head => 7

3a mine centered over the midrib, corridor or elongated blotch => 4

3b mine not associated with the midrib => 5

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

4b elongated blotch, sometimes with short lateral extensions: Liriomyza xanthocera

5a puparium in their mine in a, usually lower-surface, pupal chamber; frass in isolated grains: Chromatomyia horticola

5b pupation outside the mine; frass in strings => 6

6a larva: anterior half of yellow; rear spiraculum with 7-12 papillae: Liriomyza bryoniae

6b entire larval yellow; rear spiraculum with 3 papillae: Liriomyza trifolii

7a larva yellow, without prolegs or pinacula; the larva mines all its life=: Apteropeda orbiculata, splendida

7b larva grey or green, with prolegs and pinacula; older larvae live free => 8

8a larva green; mine flat: Antigastra catalaunalis

8b larva grey; mine more or less contracted because the inside has been lined with silk => 9

9a mine large; east mediterranean species: Cnephasia lineata

9b mines tiny; species of all Europe => 10

10a larva: pinacula colourless (the bases of the setae themselves are black) : Cnephasia incertana

10b pinacula black => 11

11a larva: behind/below the anus a chitinous comb: Cnephasia asseclana

11b anal comb absent: Cnephasia stephensiana