Wednesday, 2 April 2014

Apple Leaf-miner - melanic form

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?



  1. I wonder whether the melanic forms sometimes end up in the 'too difficult' pile for the less experienced recorders (and I include myself in that category!) which may be why not many folk have noted them. My first records of the species were from 2013 (none melanic), which might also be something to do with the Field Guide to micros coming out in 2012!

  2. I had three melanic clerkella a few days ago too, and I've not seen the nominate form as yet. Given that the weather didn't warm up until the begining of June last year I don't think you can rule out any of them having been the hibernation brood.

    I do wonder whether I over look them when there are more moths to look at in the trap, but it did strike me as odd that my first for the year again were melanic, as I distinctly recall it from last year. You could be on to something!

  3. Of course it could also be that being dark they warm up quicker!

  4. Thanks for the comments chaps. Other photos on the web also seem to back up the theory.

    I might try and get hold of data form other counties and think about writing a note for one of the journals, but that would probably be a job for next winter.