Antenna 1 and antenna 2 flagellum with 4 articles. Lacinia of right mandible with the apex trifid; molar process absent. Pleon segment 5 with a mid-dorsal, longitudinal carina. Pleotelson with an anteriorly situated mid-dorsal longitudinal carina, which bifurcates posteriorly and lacks tubercles; lateral crests of pleotelson slightly tuberculate, dorsal surface of posterior margin not so, but with a fringe of small, dorsally directed spines. Uropod exopod much shorter than the endopod and with an apical claw; endopod elongate, apex blunt, lacking claw. Pleopod 5 lacks marginal setae. Up to 3.5 mm body length.
A boreal wood-boring species, common in the North Sea.
Recorded on the east and west coasts of North America and in Europe from Norway southwards to a latitude probably little beyond southern Britain.