Body exceedingly clumsy and thickset, with the lateral processes nearly contiguous; the two median segments of the body with a longitudinal series of prominent spiniform projections on the dorsal side. Cephalon hardly as long as the three succeeding ones together, neck extremely short, almost absent. Abdomen produced, conic, partly spinous.
Ocular tubercle obtusely rounded, with well-developed eyes. Proboscis directed obliquely downwards, conic, point mamilliform exerted, oral orifice surrounded by a dense wreath of delicate bristles. Chelifores comparatively short; scape cylindrical with strong spiniform projections at the tip; chela hardly longer than the scape, triangular; immobile finger with a single rounded protuberance at the middle of the inner edge; mobile finger smooth. Palps absent.
Ovigerous legs present in both sexes; with ten segments, comparatively short, outer segments with plain, irregularly disposed spines on the inner margin.
Ambulatory legs short and robust, scarcely more than twice as long as the body; and furnished, especially along the outer side, with strong spiniform projections, delicately ciliated at the edges and bearing a stiff bristle at the point; propodus strongly curved and armed on the inner edge with 8-10 strong spines; terminal claw shorter than the propodus.
Body a yellowish brown. Length of the body up to 3.5 mm; the extent between the points of the ambulatory legs reaching 19 mm.
A shallow-water species.
A northern species, Norway, Scotland, Greenland, east coast of North America, the Murman coast and Novaja Zemlja.