I think it is Macropis europaea, a solitary bee.
For good photo, see http://molbiol.ru/forums/lofiversion/index.php/t133599-450.html
(search for 'Macropis' on that page).
For general info on this species, especially re Britain, see
But there are quite a few similar species.
If you could tell us where you found it, the date (month would help), and its size, that would help.
Many thanks for your reply.The photos were taken in my garden in Cornwall on 29th. Sept. 2012.The size, from memory,would be about 18mm long.I have looked at the photos of Macropis and it appears very similar but there are no 'wetlands' in the area,although there is a river,and some of the 'flowers visited' are local.It is interesting that the BWARS map does not record any sitings in Cornwall.I have another photo, which is attached,showing the stripes on the right hand side of the abdomen diverging.The stripes appear to form a narrow V with the base on the left of the abdomen and the top of the V on the right.This is not seen in the BWARS photos but might help identification.Looking forward to your futher comments.
Thanks for the further photo.
The V-shapes are due to distention of the abdomen, which is accomplished by a degree of articulation between the segments; not of help in identification but thanks for the thought.
Based on the key in Chinery, M. (Collins Field Guide: Insects of Britain and Northern Europe, 3rd edition, 1993, pp.278-281):
1. Two submarginal cells (not three) --> 19 (not Apis / Anthophora / Psithyrus / Bombus / Xylocarpa / Melecta / Tetralonia / Ceratina / Sphecodes / Nomada / Colletes / Crocisa / Epeolus / Melitta / Andrena / Halictus / Lasioglossum)
19. radial cell of forewing long and narrow, coming to a point on the wing margin quite close to the wing tip -- > 20 (not Panurgus / Dasypoda / Eucera / Hylaeus / Anthidium / Stelis / Coelioxys / Heriades / Chelostoma / Megachile / Osmea / Hoplitis)
20. 1st discoidal cell extends beyond junction of 1st and 2nd sub-marginals --> 22 (not Dasypoda / Dufourea)
22. abdomen rather rounded: smooth and shiny at front --> Macropis
abdomen mainly dull black with clear bands of pale hair --> Rhophites (not recorded in the UK)
So that gets me to Macropis, and specifically M. europaea.
- I am not confident of my interpretation of the venation from your photos
- The size may be wrong (M. europaea is about 12mm long)
So there is still scope for it being, one of the others, eg. Colletes sp.
You could work through the BWARS list of Colletes species (follow link on http://www.bwars.com/index.php?q=species_gallery/Bee) to check for appearance and distribution, etc.
If you can help on the venation that would be useful, but I suspect you have no more photos and can see no more detail on the existing ones than I can.
Other opinions welcome...