1a mine upper- or lower-surface; feeding lines sometimes visible; larva a maggot => 2

1b mine full depth; never feeding lines; larva with chitinised head => 10

1c fleck mine (lobe case) => 15

1d small mine, not much larger than the puparium that it contains: Hydrellia griseola

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

2a a gallery form begin to end => 3

2b blotch, may be preceded by a gallery => 6

3a gallery pinnately branched, main branch overlying the midrib: Liriomyza strigata

3b gallery not associated with the midrib => 4

4a frass in strings along the gallery sides; pupation outside the mine => 5

4b frass in discrete grains; pupation in the mine in a, usually lower-surface, pupal chamber: Chromatomyia horticola

5a the gallery usually starts lower-surface, later becoming upper-surface (and then often forming a secondary blotch); larva: rear spiraculum with 7-12 papillae: Liriomyza bryoniae

5b gallery upper-surface, only rarely forming a secondary blotch; rear spiraculum with 3 papillae: Liriomyza trifolii

6a blotch without, or with only a short, broad, preceding gallery => 7

6b blotch preceded by a long, narrow gallery (sometimes overrun by the later blotch, but then still recognisable in the frass pattern) => 8

7a “blotch”, no more details given; southern Europe: Amauromyza balcanica

7b large transparant blotch without, or with only a short, broad, preceding gallery; feeding lines conspicuous; NW Europe: Agromyza flavipennis

8a frass in the gallery part in a broad green central band, with tiny black granules at either side: Amauromyza labiatarum

8b frass in the gallery in black grains or thread fragments => 9

9a frass in the entire gallery as neat thread fragments, alternating along the sides: Amauromyza lamii

9b frass in the gallery in shorter, untidily arranged thread fragments; towards the end more in grains: Amauromyza morionella

10a mine small, of indefinite shape, often several together => 11

10b mine a definite gallery => 14

11a larvae whitish-hyaline, apodous; mine not associated with spinning => 12

11b larve grey, with feet and prolegs; spinning often visible => 13

12a older larvae live free under the leaf: Phytosciara halterata

12b the larvae mine all their life: Phytosciara macrotricha

13a larva: head pale brownish; prothoracic plate not differentiated: Prochoreutis myllerana (occurrence on Lamium uncertain)

13b head chestnut, prothoracic plate shining blackish brown with a broad wide anterior margin: Cnephasia incertana

14a larva without feet; mine begins in the leaf base, initially some gallerys, later more blotchy: Orthochaetes insignis

14b larva with thoracic feet; mine not bound the the leaf base, more densely wound, often a secondary blotch: Apteropeda globosa & orbiculata

15a anal end of the case clearly curved downwards: Coleophora ballotella

15b anal end, seen from the side, straight => 16

16a case flattened, especially near the tip: Coleophora lineolea

16b case hardly flattened: Coleophora ochripennella