Based on adult male. Antenna 1 shorter than antenna 2; flagellum article 1 distinctly elongate. Antenna 2 less than 40% of body length; calceoli present. Eyes large, reniform. Lateral cephalic lobes broadly rounded. Maxilliped palp 4-articulate; inner plate poorly developed, not reaching half length of outer plate.
Gnathopod 1 subchelate; coxa large, about as long as coxa 2, subrectangular with concave anterior margin or broadly expanded anterodistally; ischium short; carpus short, of subequal length to propodus; propodus margins tapering slightly, palm transverse. Gnathopod 2 subchelate; carpus longer than propodus. Pereopods 3 and 4 propodus with blunt, locking robust setae at posterodistal corner. Pereopod 5 coxa equilobate; basis distinctly longer than broad.
Epimeron 1 anterodistal corner acute, or producing small, up-turned spine; epimeron 3 posterodistal corner produced, forming a large upturned spine. Urosomite 1 with dorsal depression, not dorsally carinate. Uropods 1 and 2 rami subequal; uropod 2 inner ramus with marginal constriction; uropod 3 outer ramus 2-articulate, article 2 short, rami subequal. Telson distinctly longer than broad, deeply cleft.
Female (sexually dimorphic characters): Calceoli absent. Lateral cephalic lobes subacute or narrowly rounded.
North Atlantic, North Pacific and Arctic Oceans.
Usually found on sandy sediments in shallow water.
Infralittoral to circalittoral.