1a mine small, of indefinite shape; larva with recognisable head and thoracic feet; older larva lives free, among spun leaves: Cnephasia incertana

1b mine not unusually small, a definite corridor or blotch; larva, a maggot, mines all its life => 2

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

2a blotch: Calycomyza humeralis

2b corridor => 3

3a pupation in the mine, in a, usually lower-surface, pupal chamber: Chromatomyia cf syngenesiae

3b pupation external => 4

4a corridor pinnately branched, main and side branches on top of midrib and side veins: Liriomyza strigata

4b corridor winds through the leaf without regard to the venation: Liriomyza bryoniae