Petunia
Dichotomous table for leafminers
1a pupation within the mine, in a, usually lower-surface, pupal chamber; frass in isolated grains: Chromatomyia horticola
1b pupation outside the mine; frass in strings => 2
1c galls, etc => Tables for all parasites per species
2a corridor pinnately branched; main and side branches on top of midrib and side veins: Liriomyza strigata
2b corridor less, and not pinnately, branched, not associated with the leaf venation: Liriomyza bryoniae
Not included in the key: Liriomyza trifolii; Tuta absoluta.