This species is readily recognised by the characteristic shape of the first antenna. Body elongate, cylindrical; urosome small and dorsoventrally flattened , usually reflexed beneath pereion. Coxal plates 1 to 4 very short, discontiguous; plate 5 with moderately large anterior lobe. Head broad, rostrum elongate and spine-like, lateral lobes narrowly produced, rounded; eyes small and rounded. Antennae robust and densely setose; antenna 1 peduncle article 1 extremely large and as long as articles 2 and 3 combined, distal angle prolonged into large rounded lobe, flagellum very short, 2-articulate. Antenna 2 about as long as 1, flagellum short, 2-articulate. Gnathopod 1 carpus with setose posterior lobe, propodus oval, palm oblique, setose, dactylus inner margin with tooth. Female gnathopod 2 simple, basis broad, carpus elongate, propodus about equal to length of carpus, narrowly oval. Male gnathopod 2 extremely large and carpochelate, basis oval, very broadly expanded, carpus very robust with posterior margin produced into 3 large teeth, propodus slender, elongate, posterior margin crenulate, dactylus large and closing against mid-posterior margin of carpus, inner margin weakly setose. Pereiopods 3 and 4 basis oval; pereiopod 5 short, merus very broad and overlapping small carpus; pereiopods 6 and 7 slender and more elongate. Uropod 1 biramous, peduncle outer margin spinulose, distal margin and outer margin of outer ramus minutely serrate: uropod 2 uniramous: uropod 3 peduncle robust, ramus very small with minute apical hook. Telson short, bilobed, dorsal surface minutely spinulose.
Length up to 5 mm.
Depth range from 50 to 100 metres; this species inhabits a cylindrical membraneous tube, open at each end. The enlarged first peduncular article of antenna 1 is thought to act as an operculum to close off the tube.
North Sea; English Channel.