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Sarcophaga is much bristlier, with redder eyes, shorter wings relative to abdomen, and you'd expect to see a strongly kinked central vein on the wing - not a series of more parallel veins as here. Flies are tough... so many subtly different families, but this looks more like a female Anthomyiidae to me, but I find them hard to separate from Fanniidae or some Muscidae and there may be other possibles... It would take a dipteran expert and maybe more angles of view to be sure. eg clear top view of wing veins.
Nick Upton, naturalist and photographer.
When time allows I will use the above info to do some research. I say when time allows as this retirement game consumes so much time its difficult to fit everything in (or is it slowing down with age ??????)
Lat/Lng: 51.90605, 0.9057
OS grid ref: TL999270