---

Muscina prolapsa was my first thought too, although vein M1 is rather strange, almost straight. Compare it, for instance, with this fly of mine: http://www.dipter...post_22087, also (presumed) M. prolapsa.
I still wonder about M. pascuorum, a species of which I can find little information, and how to seperate it from prolapsa.
But look at this thread: http://www.dipter...post_18551, with a fly of which Tony suggests it might be pascuorum, it also has quite a straight M1.