1a mine small, of indefinite shape, not starting at an egg shell; the older larva lives free, among spun leaves => 2

1b mine not particularly small, a corridor, blotch, or a combination, always starting at an egg shell (not always easily visible); the larva either mines all its life, or ends living in a folded leaf margin => 4

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

2a larva: behind/below the anus a chitinous comb => 3

2b anal comb absent: Cnephasia incertana

3a larva: pinacula lighter than the integument: Cnephasia longana

3b pinacula black: Cnephasia asseclana

4a tentiform mine; the older larva lives in a folded leaf margin => 5

4b no tentiform mine; life long miners => 6

5a species of Madera and the Canary Islands: Caloptilia aurantiaca

5b species of continental Europe: Euspilapteryx auroguttella

6a blotch, without a trace of an initial corridor: Leucoptera lustratella

6b initial corridor always present, albeit sometimes overrun by the later blotch => 7

7a initial corridor epidermal, with little frass => 5

7b initial corridor deep, almost stuffed with frass => 8

8a pupation external; species of the Canary Islands: Fomoria variicapitella

8b pupation in a cocoon within the mine; species of continental Europe => 9

9a egg at the upper side of the leaf: Fomoria luisae

9b egg at the lower side => 10

10a species of Greece: Fomoria deschkai

10b species of entire Europe (Greece included!): Fomoria septembrella