This small black fly on hogweed has an upturned 'collar' behind the thorax.
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What you are seeing is the scutellum, but it is not actually upturned. I think it appears so as the alula of the wing has turned up at the side of the scutellum, making the whole thing seem upturned.
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The alula of a hoverfly wing is new to me. I found the abstract of an article explaining it is an indicator of 'gear change' in hoverfly flight.
Lat/Lng: 50.6679, -1.1752
OS grid ref: SZ583856