Female easily confused with Dyopedos porrectus . Coxal plates very small; plate 1 in male prolonged into a spiniform process, which curves inwards ventrally. Head prolonged slightly forwards; eyes large, rounded, protruding. Antenna 1 equal or little less than the body length, setose, flagellum equal to the length of the peduncle article 3, 5-articulate; accessory flagellum very small, 3-articulate. Antenna 2 about three-quarters of the length of antenna 1, densely setose, slender. Gnathopod 1 small, simple, carpus much longer than the propodus. Female gnathopod 2 small, carpus triangular, propodus oval and much longer than the carpus, palmar margin with a single slender median spine, dactylus more than half the length of the propodus. Male gnathopod 2 extremely large and robust, basis with a large anterodistal lobe, carpus well developed, propodus massive and very densely setose on inner surface, palmar margin with a spiniform proximal process and a triangular distal tooth, dactylus robust, setose, inner margin strongly sinuous with a large proximal tubercle. Pereiopods 3 and 4 small, basis expanded, oval. Pereiopods 5 and 6 moderately elongate, carpus spinose, dactylus very small; pereiopod 7 occasionally very long and robust in large specimens. Uropods 1 and 2 peduncle outer margin and rami with the margins minutely toothed, spinose; uropod 2 peduncle inner margin with a few short setae; uropods 1 and 2 outer ramus only little shorter than inner; uropod 1 rami with a long apical spine. Telson rounded.
Up to about 7.5 mm.
Pale yellow, mottled with brown.
Depth range from 15 to 325 metres.
North Atlantic, American and European coasts; Arctic Ocean. European coasts from northern Norway and Iceland to the English Channel.