1a mine full depth; larva with chitinised head => 2

1b mine upper- or lower-surface; larva a maggot => 5

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

2a mine small; larva grey, with thoracic feet; older larvae live free among spun leaves => 3

2b mine not remarkable small; larva, light brown, without feet, mines lifelong: Orthochaetes setiger

3a larva: pinacula colourless (the bases of the setae themselves are black): Cnephasia incertana

3b pinacula black => 4

4a larva: behind/below the anus a chitinous comb: Cnephasia asseclana

4b anal comb absent: Cnephasia stephensiana

5a upper-surface blotch with conspicuous secondary feeding lines => 6

5b no secondary feeding lines visible => 7

6a mine not associated with the midrib: Liriomyza pusilla

6b mine centered over the midrib: Trypeta immaculata

7a mine not associated with the midrib => 8

7b mine centered over the midrib => 9

8a frass in isolated grains; pupation in the mine in a, usually lower-surface, pupal chamber; mine not unusually long: Chromatomyia cf. syngenesiae

8b frass in strings; pupation after the mine has been vacated; mine starts with an unusually long lower-surface corridor: Phytomyza marginella

9a larva in the midrib that is swollen like galled (not a true mine, in fact): Phytomyza cecidonomia

9b midrib not galled => 10

10a broad irregular blotch, usually on top of the midrib; frass powdery, dark green, in “cloud” in remote corners of the mine (open the mine!): Scaptomyza flava

10b a gallery; frass, if present, as black grains or strings => 11

11a mine pinnately branched; pupation after the mine has been vacated; frass in strings in the corridor and its side branches; larva: cephalic skeleton with two rearwards pointing arms: Liriomyza strigata

11b larva lives in the midrib, from where it makes short excursions into the lamina; these corridors almost free of frass, which is accumulated in the base of the hollow midrib; there also the puparium; larva: cephalic skeleton with three rearwards pointing arms => 12

12a larva: front spiraculum points right up, spinelike: Ophiomyia pulicaria

12b larva: front spiraculum bent, broad: Ophiomyia beckeri & cunctata