Ranunculus buttercup
Incl. Batrachium, Beckwithia, Ficaria.
Dichotomous table for leafminers
1a mine full depth; larva with feet and chitinised head => 2
1b mine upper or lower-surface; larva a maggot => 3
1c galls, etc => Tables for all parasites per species
2a blotch mine; larva with abdominal and thoracic feet: Pseudodineura fuscula
2b corridor mine; larva without abdominal feet: Orthochaetes insignis
3a mine a very short and narrow corridor that ends upon a thick vein: Phytomyza clematidis
3b mine different => 4
4a mine consists of some corridors that radiate from the leaf base: Phytomyza stolonigena
4b mine entirely within the leaf blade, corridor or blotch => 5
5a puparium in the mine; primary or secondary blotch => 6
5b pupation outside the mine; corridor, sometimes secondary blotch => 8
6a primary blotch, no secondary feeding lines: Phytomyza rydeni
6b secondary blotch, in fresh mines secondary feeding lines visible => 7
7a mine quickly turning dark brown; puparium blackish-brown: Phytomyza fallaciosa
7b mine not quickly browning; puparium yellow: Phytomyza ranunculicola
8a clear corridor => 9
8b corridor so densely wound that a secondary blotch is formed, here and there enclosing small islands of uneaten tissue: Phytomyza buhriana
9a corridor short and broad, starting at a brown spot: Phytomyza notata
9b corridor longer and narrower, never beginning at a brown spot => 10
10a frass grains fine, separated by less than their diameter, often also fusing into pearl strings: Phytomyza ranunculi
10b frass grains coarser, their distance almost everywhere greater than their diameter => 11
11a on Ranunculus lingua; exit slit in upper epidermis: Phytomyza linguae
11b on other Ranunculus-species; exit slit in lower epidermis: Phytomyza ranunculivora
Not included in the key: Cnephasia asseclana, incertana, lineata; Coleophora fretella, rectilineella; Ctenosciara hyalipennis; Liriomyza trifolii, xanthocera; Phytomyza aquilonia, cortusifolii, palionisi; Phytosciara halterata, macrotricha.