Carapace appreciably narrowed anteriorly, relatively smooth and with numerous hook-setae, frontal region produced as a small short rostrum with a U-shaped incision and with distally converging margins; margins of supraorbital eaves spinose or tuberculate, eyestalks always totally visible from dorsal aspect and with a prominent tubercle; peduncular segments 2 and 3 of antenna slender, postorbital spines absent; second to fifth pereiopods slender and with numerous long hook-setae, dactylus of fourth and fifth strongly curved with inner margins spinose. Female chelipeds slender. Male chelipeds robust, propodus swollen, distally compressed and subacute, in large specimens obliquely truncate distally, dactylus with subacute process on inner margin.
Carapace length up to 8 (12) mm.
Depth range from 5 to 70 metres, on hydroids, bryozoans, ascidians and on undersides of raised boulders. Ovigerous March-September.
Carapace pale reddish-yellow; chelipeds and pereiopods lighter.
?Yorkshire, East Channel, Wight, Portland, Channel Isles, Plymouth, Scilly Isles, Isle of Man, Clyde & Argyll, Mayo, Galway Bay, Cork.