Epimeral plate 3 posterodistal angle quadrate. Eyes rounded, black in colour. Antenna 1 scarcely reaching end of peduncle article 4 of antenna 2, flagellum about 6-articulate. Antenna 2 up to one-third body length, peduncle robust in male, flagellum little shorter than peduncle, up to about 20-articulate. Antenna 2 less robust in female than male. Male gnathopod 1 carpus and propodus with prominent posterior lobe, propodus little shorter than carpus, palm transverse, dactylus shorter than palm. Female nathopod 1 carpus and propodus without posterior lobe, dactylus little longer than palm. Male gnathopod 2 propodus very large and robust, broadly oval, palm less than half posterior margin, oblique, convex, delimited by rounded process, dactylus curved. Female gnathopod 2 basis broad proximally, anterior margin slightly sinuous, carpus with asymmetrical posterior lobe, propodus of mitten-type. Pereopod 7 basis broad; in male merus and carpus more or less expanded and may be especially broad in large specimens; in female and small males merus and carpus basic; propodus slender and straight. Pleopods with rami less than two-thirds length of peduncle. Telson fleshy, with several small marginal spines, apex with small notch.
Up to 18 mm.
Brown or greenish brown.
Has a wide habitat range from shallow water and intertidal marine and estuarine areas, to damp semiterrestrial habitats well away from water. Most frequently found beneath decaying debris around the high water mark on shingle shores. Locally very abundant.
North East Atlantic; North Sea; Mediterranean. Widespread and frequently recorded on European coasts from western Norway and Iceland to Mediterranean and Black Sea; also South-West Africa.
Source: Lincoln, 1979.