Hygrotus impressopunctatus

This individual came to light. At the time I got a bit confused with Duff's couplet 1 in the Coelambus subgenus key as the angle I thought was being referred to was clearly obtuse, so neither c. 45° as it should have been nor "very acute" as the other option would have been. As I don't appear to have photographed the relevant bit and didn't retain the specimen I can't be sure but I think I must have misread it and been looking at the wrong angle. Anyway, the other characters were in this couplet were clear enough so I don't think this affects the ID.

Hygrotus impressopunctatus showing mostly coarse elytral punctures and striae, Wendling Beck Environment Project (Norfolk, UK), 9th August 2023

My next one came to light and I didn't have any problem with my angles this time. I did however struggle with the key to subgenera as I felt the underside was brownish not black (with or without a yellow abdomen). I couldn't see any bead on the fore margin of the clypeus and I thought the body shape fitted subgenus Coelambus better but keyed it both ways just in case. Keying it as subgenus Hygrotus ended up at a species that was too small and didn't look like my specimen so I figured I was correct in thinking it was subgenus Coelambus. The beetle was 4.8mm long.

Hygrotus impressopunctatus showing base of elytral epipleura, hind tarsal claws, clypeus and elytra (showing punctures and striae), Wendling Beck Environment Project (Norfolk, UK), 18th August 2024