Eyes very large in male, kidney-shaped, red-brown in colour; in female small, oval, black in colour. Antenna 1 flagellum 5 or 6-articulate; accessory flagellum small, 3 or 4-articulate. Antenna 2 flagellum 2-articulate in female with article 2 minute; in male flagellum filiform and longer than body. Gnathopod 1 carpus strongly expanded, setose, propodus very much smaller than carpus, oval; gnathopod 2 carpus less strongly expanded, setose, propodus more slender with palm transverse. Pereiopod 5 basis short and very broadly expanded, carpus broader than long, but width not exceeding twice length and often much less, carpus much broader than merus, propodus broad and robust, dactylus moderately broad and about straight; merus, carpus and propodus with many long strong spines. Pereiopods 5 and 6 with numerous plumose setae. Pereiopods 6 and 7 carpus and propodus about equal length. Uropod 1 peduncle robust and strongly spinose, rami about equal length, straight proximally and weakly curved towards apex, outer ramus with 2 small spinules, inner ramus occasionally with small seta; uropod 2 peduncle short and stout, rami longer than peduncle, straight, smooth, outer ramus occasionally with small spinule; uropod 3 moderately setose, inner ramus equal to length of article 1 of outer ramus. Telson broader than long, apex of each lobe with single seta and small spinule.
Up to 5 mm.
Female yellowish tinged with violet, male yellow with dorsal pereion and margins of epimeral plates bright red.
Depth range from 0 to 10 metres.
North East Atlantic; North Sea; English Channel; from east Scotland to the Mediterranean; North Africa to Senegal; Canary Islands.