Carapace appreciably narrowed anteriorly, frontal region produced as a tapering rostrum, thin, long and deflected slightly upward and extending well beyond distal end of fifth peduncular segment of antennal peduncle, carapace surface with numerous hook-setae prominent on rostrum, regions swollen and with tubercles; a spine between subhepatic swelling and basal segments of antennal peduncle; second and third peduncular segments of antenna slender and with ventral spines; eyestalks totally visible from dorsal aspect. Second to fifth pereiopods very thin, merus of second much longer than length of carapace and rostrum, and dactylus as long as dactylus of fourth and fifth pairs of moderate length and curved, spines on inner margin of dactylus small, well spaced, alternating in size and extending whole length of margin. Female chelipeds slender. Male chelipeds large, propodus inflated, no appreciable 'gape' between inner margin of propodal prolongation and dactylus.
Carapace length up to 16 (32) mm.
Depth range from 10 to 100 metres, on mud to hard ground and on Sertularella colonies, also in estuaries; ovigerous crabs and larvae throughout year.
Shetland, Moray Firth, Aberdeen, Northumberland, York-shire, Wash, Thames, East Channel, Wight, Portland, Channel Isles, Plymouth, Scilly Isles, Isle of Man, Dublin, Belfast, Clyde & Argyll, Fastnet.