See also the closely related genus Leontodon.
Dichotomous table for leafminers
1a long slender gallery, larva a maggot => 2
1a galls, etc => Tables for all parasites per species
2a gallery ± pinnately branched; larva pupates after having left the mine: Liriomyza strigata
2b gallery irregularly branched, larva pupates in the mine, in a, normally lower surface, pupal chamber: Chromatomyia cf syngenesiae