Eyes very large in male and almost joining on top of head, in female moderately large and kidney-shaped; black in colour. Antenna 1 flagellum 7 or 8-articulate; accessory flagellum well developed and about 7-articulate, only little shorter than primary flagellum. Antenna 2, peduncle in male with few plumose setae, flagellum in female 4-articulate and shorter than peduncle article 5, in male filiform and about three-quarters body length. Gnathopods 1 and 2, carpus elongate and strongly expanded, setose, propodus very much smaller than carpus and very narrow proximally. Pereiopod 5 basis very broadly expanded, carpus only slightly broader than merus and little broader than long, propodus moderately robust, dactylus broad with anterior margin curved and distally weakly crenulate. Pereiopods 5 and 6 with numerous plumose setae. Pereiopods 6 and 7 propodus shorter than carpus. Uropod 1 peduncle slender, rami slender, about equal, straight proximally and slightly curved towards apex, outer ramus with 3 spinules, inner ramus with 1 to 3 short setae; uropod 2 peduncle short, rami about equal, about equal to length of peduncle, outer ramus with 1 to 3 spinules; uropod 3 rami about equal length, densely setose. Telson little longer than wide, apex of each lobe with 1 spine and 2 setae.
Up to 7 mm.
Depth range from the intertidal, about mid-tide level, to about 40 metres; locally common.
North Sea; English Channel; Atlantic coast of France and British Isles.