Fly on bare ground on a scrubby heath
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Worth bearing in mind that male Haematopota pluvialis are also quite dark. The point about the eyes, I have not heard before...I don't think it is any different between the two? I think the ID is right, but not for the reasons given, maybe.
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Lat/Lng: 52.6905, -1.9675
OS grid ref: SK022103