Urosome segment 1 with a prominent dorsal tooth. Coxal plates 3 and 4 with the distal angles acutely produced, margins weakly setose, plates 5 to 7 rounded. Epimeral plate 3 distal angle with a small tooth. Head with broadly rounded lateral lobes, outer margin with a small tubercle; eyes moderately large in female, very large in male, rounded oval, visual elements distinct. Antennae of about equal length in female, antenna 1 shorter than antenna 2 in male, sparsely setose; antenna 1 peduncle articles 1 and 2 about equal in length, article 2 tapering distally, article 3 very small, flagellum up to 25-articulate. Antenna 2 peduncle article 4 longer than article 5; in male article 4 with many short fine setules on the anterior margin. Female gnathopod 1 basis robust, propodus broadly oval, much longer than the carpus, palm oblique, convex, delimited by a slender spine, inner surface very densely setose, dactylus with a long outer-marginal seta. Male gnathopod 1 similar to the female except propodus with a deep cleft in the anterior margin. Gnathopod 2 a little longer and more slender than gnathopod 1, propodus broad distally, a little shorter than the carpus, palm oblique, convex, delimited by a pair of slender spines, dactylus with a long outer-marginal seta; merus, carpus and propodus only moderately setose. Pereiopods 3 to 7 spinose, merus much longer than the carpus and propodus together, carpus with three or four strong distal spines; pereiopod 5 basis not expanded; pereiopod 6 basis with a small proximal expansion; pereiopod 7 basis weakly expanded proximally. Coxal gills weakly pleated. Uropods 1 and 2 spinose; uropod 2 much shorter than uropod 1; uropod 3 rami longer than the peduncle, spinose with long marginal setae. Telson elongate, almost as long as uropod 3, cleft to the base, each lobe with a few outer-marginal spinules.
Up to about 6 mm.
Whitish, with brown patches.
Depth range from the intertidal to about 150 metres; locally common especially with sponges and ascidians. Not found intertidally in the northern part of range.
North-East Atlantic; North Sea; European coasts from Norway to the Mediterranean; also Black Sea, North Africa to Senegal; Azores.