Melissa lemon balm
Dichotomous table for leafminers
1a fleck mine; larva mines from a tubular case: Coleophora albitarsella
1b orridor or blotch mine => 2
1c galls, etc => Tables for all parasites per species
2a mine small, irregular in shape, full depth; older larvae live free among spun leaves: Cnephasia incertana
2b mine large, upper-surface; larva mines all its life => 3
3a mine a slender gallery that abruptly widens into a large blotch: Amauromyza labiatarum
3b mine an irregular, sometimes branching, gallery up to the end: Phytomyza petoei