1a pinnately branched corridor on top of the midrib and strong lateral veins: Liriomyza strigata

1b elongated blotch on top of the midrib: Liriomyza xanthocera

1c corridor not associated with the leaf venation => 2

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

2a frass in isolated grains; puparium in the mine, in a, usually lower-surface, pupal chamber; mine shallow: Chromatomyia horticola

2b frass in strings; pupation outside the mine => 3

3a larva: rear spiraculum with 7-12 papillen: Liriomyza bryoniae

3b rear spiraculum with 3 papillen => 4

4a gallery usually forming a secondary blotch; frass in long strings: Liriomyza valerianae

4b rarely a secondary blotch; frass in short strings: Liriomyza trifolii