Thread subject: Diptera.info :: Anthomyia sp.
Posted by davenicholls on 07-06-2011 21:57
#1
Is it possible to say which species of Anthomyia this is? Found in England in early June.
Many thanks.
Posted by Stephen R on 08-06-2011 10:36
#2
If the black area above the wing base is divided into two distinct spots it could be
A. pluvialis. If, as it appears from this view, the spots are united, but with a notch in the rear margin of the black patch,
A. imbrida is more likely.
A. procellaris is similar but usually has a straight rear margin to the united spot. But other features are needed too, and you would need a male specimen and a microscope to be sure. This info is from Michael Ackland's key.
Posted by davenicholls on 08-06-2011 11:58
#3
Many thanks Stephen, it is really helpful to get some guidance on separating the species in this genus. I've tried looking for an example of the two spots in pluvialis but can't see this feature clearly - even the image in the gallery appears to show a combined black spot - or am I mistaken?
http://www.diptera.info/photogallery.php?photo_id=841
Posted by Stephen R on 08-06-2011 13:27
#4
If you look at the comment attached to that image you will see that Jorge has questioned the ID on exactly that point. I'm not sure I've seen an image with two clear spots either; I think
A. pluvialis may be quite scarce! I wonder if in a truly lateral view you might be able to see a division on your fly. I don't know how marked the separation needs to be. Perhaps Michael will comment.
Edited by Stephen R on 08-06-2011 13:38
Posted by nielsyese on 08-06-2011 20:23
#5
Look at this picture: http://www.diptera.info/photogallery.php?photo_id=2799 The separation of the spots is very clear, but maybe there are cases in which it is not. To my experience, in the Netherlands A. pluvialis is much more rare than A. procellaris, the last one is very numerous here.