Dryas mountain avens
Dichotomous table for leafminers
1a fleck mine, larve mines from a portable case => 2
1b no fleck mine; larva mines from the inside => 4
1c galls, etc => Tables for all parasites per species
2a spatulate leaf case: Coleophora unigenella
2b tubular silken case => 3
3a full grown case before the end with a constriction: Coleophora nubivagella
3b full grown case not constricted: Coleophora derasofasciella
4a corridor along the leaf margin, then widening into a blotch; larve mines all its life: Stigmella dryadella
4b blotch; if an initial corridor is at all visible, it does not run along the leaf margin; the older larve lives free in a leaf that is spun into a pod: Parornix alpicola *
* see also Parornix scoticella.
Not included in the key: Stigmella tatrica (biology unknown, host plant not quite certain).