Carapace regions clearly delineated, dorsal surface with transverse rows of tuberculate carinae, submedian lobes broad. Antero-lateral margins of carapace with five acute or subacute tuberculate teeth. Chelipeds moderately stout, unequal in size and tuberculate, propodus with longitudinal tuberculate carinae; second to fifth pereiopods moderately stout and moderately compressed, dorsal margin of merus spinulate and dorsal surface of carpus-dactylus with dense setae. Female chelipeds less unequal in size than in male.
Carapace length up to 13 (18) mm.
Depth range from 7 to beyond 180 metres, on sand, sandy mud and gravel and on Modiolus beds. Ovigerous April-July.
Carapace reddish-brown, distal propodus and dactylus of chelipeds black or brown.
Yorkshire (Adema & Creutzberg, personal communication), Plymouth, Anglesey, Liverpool Bay, Isle of Man, Belfast, Clyde & Argyll, Fastnet.