Shell small, glossy, semitransparent when fresh, conical; whorls tumid and sutures deep; apart from growth lines ornament variable, but if present always in the form of spiral cords. Aperture small and oval, outer lip angulated if a spiral ornament is present and a little everted basally; umbilicus obvious. Ten to eleven whorls, about four of which belong to the protoconch and are always smooth; the others may be smooth but more commonly bear some spiral ridges of varying degrees of clarity: they may be evenly spaced or concentrated on the basal half of each whorl and may be either sharp or rounded in section. There may be 3-5 on the last whorl, 2-4 on those of the spire. There is always a smooth area between suture and the first spiral ridge. Last whorl occupies 40-45 % of shell height, aperture about a quarter.
Up to 6 x 2.5 mm.
The animal is without a snout, the head forming a ledge with tentacles at its anterior margin and the opening of an introvert below it. The tentacle bases are close together and an eye lies behind and lateral to each. The foot has a mentum (an enlarged lobe of the propodium, dorsal to the anterior end) and is broad in front, tapering behind. The right opercular lobe is larger than the left. The body is white. The way of life of this and other aclidids is unknown, but the presence of an acrembolic proboscis strongly suggests that the animals are carnivores.
Sandy bottoms from 15-150 m. Either not common or hard to find because of their size.
From the Mediterranean to southern Scandinavia (Distr. A. minor). Several records from the British Isles.