Saw this in a nettlebed where I was searching for banded snails.
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In the same group as the Eristalis spp. you've been seeing, this is a species in genus Helophilus, probably H. pendulus (but ideally need to see hind tibia clearly). Breeds in damp organic matter, including farmyard drains, manure and edges of wetlands.
Entomologist and biological recorder
Lat/Lng: 52.0, -0.8
OS grid ref: SP8837