Marrubium white horehound
Dichotomous table for leafminers
1a fleck mine; larva mines from a trnasportable case => 2
1b blotch, may be preceded by a corridor => 4
1c galls, etc => Tables for all parasites per species
2a lobe case: Coleophora lineolea
2b composite leaf case => 3
3a case composed of a series of many (c. 15) leaf fragments: Coleophora onopordiella
3b … less then 10 leaf fragments: Coleophora ballotella
3c (the case of Coleophora hiberica is unknown)
4a large blotch, no trace of an initial corridor => 5
4b blotch, preceded by a long, hardly widening, corridor (may be overrun by the later blotch, but recognisable from the frass pattern when lighted from behind) => 6
5a at the start of the mine the oviposition site is covered by a shining black drop of dried secretion: Trachys goberti
5b no such drop: Dibolia depressiuscula, cynoglossi
6a frass in the corridor part in a broad green central band, with tiny black granules at either side: Amauromyza labiatarum
6b frass in the corridor in black grains or thread fragments => 7
7a frass in the entire corridor as neat thread fragments, alternating along the sides: Amauromyza lamii
7b frass in the corridor in shorter, untidily arranged thread fragments; towards the end more in grains: Amauromyza morionella