1a mine upper- or lower-surface; frass in two lines; larva a maggot => 2

1b mine full depth; frass in a single line; larva with chitinised head => 9

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

2a corridor from start to end => 3

2b narrow, hardly widening corridor, suddenly widened into (and often overrun by) a large blotch => 6

3a first part of the corridor in a tight spiral; leaf tissue there often discoloured: Liriomyza eupatorii

3b no spiral => 4

4a corridor pinnately branched, its main branch overlying the midrib: Liriomyza strigata

4b corridor not pinnate, independent from the midrib => 5

5a frass in widely spaced grains; puparium in the mine, in a, usually lower-surface, pupal chamber: Chromatomyia horticola

5b frass in strings; pupation outside the mine: Liriomyza bryoniae

6a gallery gradually widening into a blotch; blotch usually on top of the midrib: Liriomyza xanthocera

6b gallery changes abruptly in a blotch, that may be situated anywhere on the leaf => 7

7a frass in the corridor part of the mine in a broad, green central band, with minute black granules at either side: Amauromyza labiatarum

7b frass in black grains and thread fragments => 8

8a frass in the entire corridor in neat thread fragments, alternating along the sides: Amauromyza lamii

8b frass in the corridor in shorter, untidy fragments; towards the end mainly in grains: Amauromyza morionella

9a mines small, variable, of indefinite shape; the older larvae live free among spun leaves => 10

9b mine not remarkably small, gallery or blotch; larvae mine all their life => 11

10a larva: pinacula colourless (the bases of the setae themselves are black) : Cnephasia incertana

10b pinacula black: Cnephasia stephensiana

11a corridor: Apteropeda orbiculata

11b blotch (may have extensions): Dibolia cynoglossi and D. depressiuscula