Hibernating larva, showing clearly the silken pad spun to keep the leaf attached. Photo: Dennis Dell


Pupation sequence from Dennis Dell, captured in one of his breeding nets. The whole process took just over an hour. Note in particular:

1. On underside before process commenced; larva is typically pallid/light green.

2. Swings clear of leaf.

4. Hump where skin is gathering up.

6. Skin split at head end..both larval and pupal horns visible.

8 Skin gathering near attached end.

10. Skin bunched up near attachment point.

Heslop describes the process in Notes and Views, page 57

Following is a photo essay by two of our more determined correspondents, whom we could never accuse of being just fine-weather lepidopterists.

An Extraordinary General Meeting of Extreme Butterflying took place on Sunday January 10th 2010 in a Wiltshire wood, with 5” of lying snow, a maximum temperature of 0C, frequent snow flurries, and depressingly bad light. 

The sole agenda item was to find and photograph hibernating larvae of Apatura iris, especially those capable of producing specimens of ab. iole.  

Doings had to be restricted to the part of the wood adjacent to the main road, the side roads and lanes being utterly impassable.  An attempt to drive to the prime iris area was thwarted by glacial conditions, the car spun into something nasty that had escaped from Antarctica and Mr Oates was forced to dig his vehicle out of a snow drift, obtaining some fine pupae of Smerinthus ocellata in the process.  

Twelve iris larvae were observed, one of which was new to science.  This was accidentally found by Mr Oates, whilst teasing down a branch already known to hold a larva.  He had nearly squashed it.  Had he done so, his life would have been forfeit. 

Mr Hulme obtained some fine photographs, primarily of the uncommon grey colour form adopted by larvae hibernating on scars or lesions in bark, or in forks.  Only two specimens were photographed of the commonest colour form, the yellow-green form that predominates when larvae position themselves by sallow buds, the most frequent location chosen for hibernation.