Thursday, 10 November 2016

Late mines - Oak and Birch

As the year draws to a close there is still time to add species to your home patch list; indeed it is almost the only time of year when Oak Stigmella are vaguely possible.  I collected several Oak leaves with 'green islands' in the SAC Parc Lodge Wood on the south-east side of the Sugarloaf today, and found that most of them held Stigmella mines complete with larvae.  Eggs on the underside and narrow black frass ruled out most species, leaving just the similar-looking Stigmella atricapitella and S. roborella.  Most larvae had dark heads, indicating the former, but a few shorter mines were occupied by larvae with pale heads, and belonged to the latter species (which has only one previous record from VC35).  It is interesting that the larvae and mines of Stigmella atricapitella were consistently larger than those of S. roborella today.

Stigmella atricapitella (left) has a black head and dark sclerite plates;
S. roborella (right) has a pale head and no dark sclerite plates

On my way from school drop-off to Abergavenny I paused briefly to record mines near Llanfihangel Crucorney.  As well as more Stigmella atricapitella and some Ectoedemia subbimaculella (see last week's post) I was pleased to spot mines of E. occultella with their distinctive central spots on Birch.  This is only the 6th county record.

2 comments:

  1. Useful as always Sam. I think that I`ll `cut and paste` your rust blogs into one document - useful for a beginner like me.

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  2. I meant -of course - to say leaf miners! I`d just been reading the rust comments on the S Wales Bryos blog (re Kenfig).

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