1a full-depth corridor or blotch; the larva spends most of its time as a stem borer: Delia echinata

1b gallery; the larve keeps within the leaf => 2

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

2a pupation within the mine, in a, generally lower-surface, pupl chamber; frass in isolated grains: Chromatomyia horticola

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

3a gallery pinnately branched; main and side branches on top of midrib and side veins: Liriomyza strigata

3b corridor less, and never pinnately, branched: Liriomyza bryoniae