Black-bellied Diving Beetle Dytiscus semisulcatus

This beast came to light during a moth survey event. Before my interest in beetles had taken off, this was pointed out to me and identified by someone else (I don't recall who). If I remember rightly the black underparts were pointed out, but in any case I think the lack of pale rear border to the pronotum points to this being the correct ID.

male Black-bellied Diving Beetle Dytiscus semisulcatus (with caddisfly, Leptocerus I think), Strumpshaw Fen (Norfolk, UK), 21st July 2012