Apium marshwort, celery, fool’s watercress
Dichotomous table for leafminers
Incl. Helosciadium
1a corridor < 1 cm long, full depth; larvae with feet and chitinised head, the rear part of their often protrudes from the mine: Epermenia chaerophyllella
1b mine larger, upper-surface; larva a maggot, always fully inserted => 2
1c galls, etc => Tables for all parasites per species
2a primary blotch mine; primary and secondary feeding lines conspicuous; larva: rear spiracula with 3 papillae => 3
2b corridor or secondary blotch without secondary feeding lines; rear spiracula with > 3 papillae => 4
3a species of continental Europe: Euleia heraclei
3b species of the Canary Islands: Euleia separata
4a puparium in the mine, mostly in an lower-surface pupal chamber; frass in widely separated grains: Chromatomyia horticola
4b puparium formed after the mine has been left; frass in strings => 5
5a mine pinnately branched, main branch overlying the midrib: Liriomyza strigata
5b mine less strongly and never pinnately branched, sometimes a secondary blotch; no association with the midrib: Liriomyza bryoniae
Not included in the key: Liriomyza trifolii.