Tuesday, 10 August 2010

Larva palaver

Identifying caterpillars shouldn't be too difficult should it -especially the big flashy ones.

When my daughter found this one strolling across a grassy footpath on the Bamburgh cliff top I took a quick photo with the plan to sort it out definitively back home.

The first two field guides I tried were inconclusive, with none of the illustrations matching this one exactly or with illustrations so small that the detail could not be made out.  This included, disappointingly,  the Collins Field Guide to Caterpillars of Butterflies and Moths in Britain and Europe.  The most helpful has been my old favourite, Margaret Brooks and Charles Knight's 'Complete Guide to British Butterflies' from 1982.

The trouble is that caterpillars can be a bit of a bother. They have to moult to grow, averaging four or sometimes five changes before full size. In some species not only does the look of the caterpillar change significantly at each moult but even the same instars of different individual caterpillars show variations in colour and pattern.

The easy bit is that spiny larvae are most likely to be members of the Nymphalidae family.
Given that this is Northumberland and we have a smaller range of species compared to the warmer southern climes, the realistic options are limited.  Although this one does not exactly fit any of the descriptions or photos I have found, on balance it's the red admiral that gets my vote but I wish I could say that with 100% conviction.    Any offers?


  1. Would Heath Fritillary (Melitaea athalia) or the European Peacock (Inachis io) be options, too? But it is really hard to tell. Good luck, anyways!

  2. Hi Dreamfalcon. I think we can rule out Heath Fritillary as this is a relatively rare british butterfly that only occurs in limited areas in the south and south west of England to the best of my knowledge.
    I did look at peacock but in all the photos and references I have found, it is primarily black and white rather than showing the colours on the spines of this one.
    I don't know how you came upon my blog but thanks for visiting and for your comment.
    Best wishes