Chamerion rosebay willow-herb
The genus Chamerion (= Chamaenerion) is alternatively split off from, and merged with Epilobium in the botanical literature. Although presently it is included in Epilobbium by the Euro+Med PlantBase, for practical reasons Chamerion is upheld here.
Dichotomous table for leafminers
1a corridor, may be followed by a blotch; corridor begins at an iridescent egg shell => 2
1b blotch, without initial corridor; mine begins at a small opening => 3
1c galls, etc => Tables for all parasites per species
2a corridor narrow, almost completely filled withh frass, not very contorted, often running along the midrib (common species): Mompha raschkiella, initial corridor
2b corridor irregular in width, contorted, frass line narrower (rare species): Mompha langiella, initial corridor
3a larvae in end May-end July or end August-September (common species): Mompha raschkiella, later mine
3b larvae in June-July (rare species): Mompha langiella, later mine
Not included in the key: Cnephasia stephensiana; Mompha epilobiella, Mompha ochraceella, Mompha sexstrigella.