Cluster Fly (Pollenia sp. and possibly P.rudis)
Turned up on the window of my office just begging to have its portrait taken. Clearly a large Dipteran and, I think, Genus Pollenia … though it could be just an old-fashioned Bluebottle (Caliphora sp.). I will amend this post once I have it nailed down better.
Cluster flies move into shelter in winter and find their way into attics and cracks in buildings. They often emerge on warm days, and cluster at windows attempting to exit(hence the name). That’s what this specimen was certainly doing. About half a centimetre long, so quite large.
P. rudis is the commonest. They came to North America long, long ago sop are “alien invaders” rather than natives. They are parasitic on earthworms and perhaps arrived in the hold of a ship with soil and plants aboard.
** … and this is the end of the first month of the 1000 Species Project. I am having a lot of fun and learning new stuff every day.