Carapace nearly circular, about as broad as long, dorsal surface with short transverse carinae; median lobe of frontal region advanced, submedian lobes acute to subacute. Antero-lateral margins of carapace with nine to eleven acute teeth often alternating in size and with tuberculate margins; antero-lateral and postero-lateral margins densely setose. Chelipeds equal, somewhat compressed, dorsal margins setose; pereiopods slightly compressed with setose margins.
Carapace length up to 28 (39) mm.
Depth range from 12 to 91 metres, on sand and gravel; frequently taken in stomachs of Gadus and Raja. Ovigerous from February-September, larvae from February-November.
Carapace reddish-brown, chelipeds and pereiopods lighter brown.
Shetland, Orkney, Viking, Moray Firth, Aberdeen, Firth of Forth, North Sea, Yorkshire, East Channel, Wight, Portland, Channel Isles, Plymouth, Scilly Isles, Bristol Channel, Liverpool Bay, Isle of Man, Dublin, Belfast, Clyde & Argyll, Minch, Galway Bay, Fastnet.