Monday, 13 June 2016

Bagworms and Clearwings

Two of Britain's oddest moth families brightened up my day.  I was working in the kitchen at 10:30 and noticed a dark-looking Micro fluttering near the doorway.  I potted it, expecting a Psychoides, but the moth was unfamiliar.  After a red herring check of the Tineidae I realised it was a member of the Psychidae (Bagworm): the almost unpronounceable Diplodoma laichartingella.  The only modern VC35 record of this reclusive moth was one I netted by day in 1999 at Cwm Coed-y-cerrig, although Horton points out that it is mapped for the county in MBGBI 2.

With Psychids on my mind, I decided it would be worth photographing the peculiar Luffia ferchaultella for the Blog.  A quick walk after work to the nearest big oaks produced good numbers of Luffia cases on the lichen-covered trunks.  Like all British Bagworms, the larvae of this species construct portable cases, which they carry around as they munch algae, lichens or plant detritus (in contrast to those other case-bearers, the Coleophorids, which mine living leaves).  Luffia ferchaultella goes one step weirder, as it is only ever female and produces its young by self-fertilizing (ie it is parthenogenetic).  The wingless adult female lays its eggs in/on the case, which provides initial food for the next generation of larvae.

While I was photographing the Luffia cases I was amazed to spot a pale brown exuvia (empty pupal case) protruding from the bark.  Further searching revealed 4 more of these tantalising signs of the presence of Yellow-legged Clearwing.  Now that I know there's a colony of this species within sight of my home, I'll make morning searches for adults and will try the pheromone lure.  Clearwings are ridiculously elusive, and I have only ever stumbled across one imago of a wood-feeding species (the herb-feeding Six-belted and Thrift Clearwings are much easier).

The only adult moth I got a good look at on the oak trunks was a Brown House-moth, which I photographed, but a one second glimpse of a pale-looking, tineid-shaped Micro with some black markings reminded me that Dystebenna stephensi really ought to be here.  Another thing to keep searching for!


1 comment:

  1. Fascinating stuff, Sam. Your posts are always interesting and informative. I have n`t seen a yellow-legged clearwing since I found them 20+ years ago on an old sweet chestnut (since felled) on the Stradey Estate, Llanelli (Carms).