Dichotomous table for leafminers
1a pupation within the mine, in a, generally lower-surface, pupal chamber: Chromatomyia cf syngenesiae
1b pupation external => 2
1c galls, etc => Tables for all parasites per species
2a corridor pinnately branched: main and side branches on top of the midrib and side veins: Liriomyza strigata
2b corridor little, irregularly branched, not determined by the leaf venation: Liriomyza bryoniae
In greenhouses other, sometimes seriously damaging, miners may occur. They are outside the scope of this site. A non-committed attempt towards a key can be found under Chrysanthemum.