Urosome segments fused; without a lateral ridge. uropods inserted laterally. Head with an acute triangular rostrum, lateral lobes prominent. Antenna 1 sparsely setose, peduncle article 1 ventral margin with 4 to 6 spines, in female spines long, in male spines may be short, proximal 2 or 3 spines curved, inner margin with 1 or 2 curved proximal spines. Female antenna 2 peduncle article 4 distal ventrolateral angle with broad obtuse process, inner ventral margin with 4 or 5 long spines, article 5 inner distal margin not produced, inner ventral margin with 1 median spine. Male antenna 2 peduncle article 4 distal ventrolateral angle with one large acute process and 1 or 2 smaller processes, inner ventral margin with 2 or 3 small spines, article 5 inner distal margin produced, inner ventral margin without spines. Gnathopod 1 palm oblique, convex. Uropod 1 peduncle outer margin with 10 or 11 spines in female, 6 or 7 in male, inner margin with 4 or 5 spines; uropod 2 peduncle inner margin with single small spine.
Up to 5 mm.
Constructs tubes of mud on algae, especially the holdfasts of Laminaria , hydroids and sponges, from the lower intertidal to depths of about 50 metres.
North Sea; English Channel; Atlantic coast of Europe from southern Norway to Mediterranean.