Posterodistal angle of epimeral plate 3 quadrate, narrowly rounded, posterior margin straight. Head with the lateral lobes weakly produced, truncated; eyes small, rounded, red in colour. Antenna 1 reaching well beyond peduncle of antenna 2, flagellum up to about 12-articulate in male, to about 9-articulate in female, flagellar articles with few long setae. Antenna 2 in male robust, more than three times length of head, flagellum up to about 15-articulate, flagellar and peduncular articles with dense tufts of long setae; antenna 2 in female less robust than in male and little shorter, flagellum up to about 13-articulate with many long setae. Gnathopod 1 basis in male robust, tapering proximally, carpus with broadly rounded posterior lobe with prominent group of long spines, propodus rectangular, palm convex and weakly oblique delimited by small spine, posterior margin with prominent group of long spines. Gnathopod 2 basis in male with broadly rounded anterior lobe, posterior margin with several short spines, propodus very large and robust, oval, palm irregularly convex, oblique, delimited by small obtuse process, dactylus robust. Gnathopod 1 in female generally similar to male except basis less robust and propodus more narrowly rectangular. Gnathopod 2 in female similar to 1, basis with more pronounced anterior lobe. Pereiopods 3 and 4 only sparsely setose, propodus usually with small group of setae on posterior mid-margin. Pereiopods 5 to 7 robust and strongly spinose, basis broadly rounded with posterior margin weakly crenulate, propodus with distinct group of long setae on posterior mid-margin. Uropods short and spinose; uropod 3 rami shorter than peduncle.
Up to 5 mm.
Variable greenish to violet, with violet markings on the coxal plates and epimeral plates.
Mediterranean; Atlantic coast of France and North Africa; Canary Islands; Azores; British Isles, north to Shetlands.