Based on adult male: Antenna 1 shorter that antenna 2, antenna 2 between 40 to 60% of body length, calceoli present. Eyes large, reniform. Lateral cephalic lobes subacute. 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; ischium short; carpus short, of subequal length to propodus; propodus margins tapering, palm transverse; dactylus well developed. Gnathopod 2 chelate; carpus longer than propodus; dactylus minute. Pereopods 3 and 4 propodus with blunt, locking robust setae at posterodistal corner. Pereopod 5 coxa equilobate; basis about as long as broad. Coxa 6 produced into a posterior lobe.
Epimeron 1 anterodistal corner producing small, up-turned spine; epimeron 3 posterodistal corner produced, forming a large upturned spine. Urosomite 1 with dorsal depression, carinate dorsally. Uropods 1 and 2 rami subequal; uropod 2 inner ramus with marginal constriction(s); uropod 3 outer ramus 2-articulate, article 2 short, rami subequal. Telson distinctly longer than broad, moderately to deeply cleft.
Female (sexually dimorphic characters): Antenna 1 subequal to antenna 2, calceoli absent.
9–11 mm. This is one of the smallest known species of Anonyx.
Mainly a North Pacific Species which seems to have spread eastwards into the North Atlantic. Found in the North and Norwegian Seas within the Northeast Atlantic.
Steele (1989) remarks that the type collection in the ZIL contains 2 small immature specimens, one of which agrees generally with the descriptions given by Gurjanova (1962) and Steele & Brunel (1968). The other specimen is quite different, however, and probably represents a different species. The former specimen should probably be designated as a lectotype.