1a mine full depth, may be very small; larva with feet and a sclerotised head => 2

1b mine shallow, a sizable corridor; larva a maggot => 3

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

2a mine tiny; older larvae live free among spun leaves: Cnephasia stephensiana

2b mine large, considerably deforming the leaf; larve mines till just before pupation: Cnephasia lineata

3a pupation within the mine in a, usually lower-surface, pupal chamber; corridor little branched; frass in discrete grains: Chromatomyia horticola

3b pupation external; corridor strongly, pinnately branched; frass in pearl strings: Liriomyza strigata