1a fleck mine => 2

1b corridor or blotch; the larve mines from the inside => 5

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

2a the larva mines from a silken web between some leaves: Sophronia humerella

2b the larve mines from a transportable case => 3

3a case irregular, covered with frass grains: Vulcaniella grabowiella

3b case covered with sand grains or leaf fragments => 4

4a opening in the mine precisely circular, surrounded by a narrow fringe of stubbles (bitten off silk threads); larva in a lobe case: Coleophora struella

4b opening not neatly round, not surrounded by stubbles; larva in a helicoidal case: Apterona helicoidella

5a larva a maggot; pupation within the mine in a, usually lower-surface, pupal chamber: Chromatomyia horticola

5b larva with sclerotised head; pupation outside the mine => 6

6a corridor, ending in a clear blotch; larva with thoracic legs: Stephensia cedronellae

6b corridor, hardly widened in the end; larva without thoracic feet => 7

7a species of the European mainland => 8

7b on L. canariensis, Canary Islands: Glaucolepis sanctaecrucis

8a on L. stoechas: Glaucolepis stoechadella

8b on L. angustifolia and latifolia: Glaucolepis lavandulae