Coxal plates elongate. Epimeral plate 3 distal angle with a minute tooth and small setule, posterior margin convex. Head with angular lateral lobes, apex subacute; eyes small to moderately large, oval. Antenna 1 up to half the body length, peduncle article 2 longer than article 1, flagellum up to about 12-articulate; accessory flagellum up to 6-articulate. Antenna 2 little shorter than antenna 1, flagellum up to about 10-articulate. Gnathopod 1 small, setose, propodus broad, oval, as long as the carpus, palm convex delimited by one or two small spines. Gnathopod 2 much larger than gnathopod 1, basis robust, carpus triangular, propodus large and robust, broad, suboval, palm strongly oblique delimited by an obtuse angle and one or two small spines, palmar margin with two small triangular processes and a small median spine. Pereiopods 3 and 4 propodus elongate oval, posterior margin with groups of stout spines. Pereiopods 5 to 7 robust, basis expanded, propodus elongate and broad distally, weakly subchelate, margin strongly spinose. Rami of uropod 3 slender, subequal in length, longer than the peduncle. Telson rounded.
Up to about 6 mm.
Yellowish brown with darker patches.
Found on the sternum, appendages and mouthparts of the lobster Homarus gammarus .
Only recorded from the British Isles and the Bay of Biscay.