I caught 3 melanic specimens of
Lyonetia clerkella in my garden trap last night which, as always, caught me out at first and made me think they were something more interesting.
Looking at my records of the melanic form, it seems obvious that this occurs mainly in the hibernating generation, presumably because they are more camouflaged than the usual white form over the winter months. My other records are from 28/9/12, 08/10/13, 29/3/11 and 06/3/13 - the former two presumably being pre-hibernation and the latter two post-hibernation.
Looking at the VC41 database, the only other records of
L. clerkella where the melanic form has been noted in the comments box are 4 records made by Dave, which don't entirely back up my theory! These are from 08/9/02, 03/05/06, 03/05/13 and 19/6/13. The first 3 could conceivably be the hibernating generation but the latter record is presumably one of the summer generation (although spring was very late last year).
There seems to be no mention in the books of the melanic form being associated with hibernation. MBGBI Vol 2 says only that it occurs as about 10% of the population.
Any thoughts? Does anyone else have any records of the melanic form which have not been recorded in MapMate?
George