1a Full depth blotch; larva with thoracic feet: Pseudodineura enslini

1b Mine not full depth, greenish in transparancy; larv a maggot, without feet => 2

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

2a Primary blotch; pupation outside the mine: Phytomyza trolliivora

2b Gangmijn of secondaire blaasmijn; verpopping binnen of buiten de mijn => 3

3a Corridor, may be strongly widened in the end; pupation outside the mine: Phytomyza trollii

3b Secondary blotch; pupation within the mine: Phytomyza trolliophila