Dorsal carapace surface with dense short, pile-like setae with clusters of larger hook-setae, carapace often invested with massive growths of epizooites and epiphytes, frontal region produced as a bifid rostrum each half distally diverging outward, preorbital spine stout, intercalary conspicuous, antorbital absent; second and third peduncular segments of antenna moderately broad, eyestalks stout, partly concealed when retracted. Antero-lateral margins of carapace with three spines, intestinal region with elevated tubercle. Chelipeds equal in size; second to fifth pereiopods with subtriangular segments (in cross-section) and moderately stout, dactylus curved. Male chelipeds larger than in female, propodus swollen, dactylus and distal part of propodal prolongation elongate or subtruncate.
Carapace length up to 33 (55) mm.
Depth range from 1 to 90 metres, chiefly on hard ground. Ovigerous crabs April-August, larvae July-September.
Carapace and pereiopods (naked) reddish brown.
East Channel, Wight, Portland, Channel Isles, Plymouth, Scilly Isles, Isle of Man, Fastnet.