Shell glossy, slightly transparent, with a pearly lustre; a moderately tall cone of 5-6 whorls with a markedly stepped profile. Ornament of low prosocline costae and spiral ridges of which the most prominent (on the last whorl) are one near suture, three at periphery, and one round umbilicus. Aperture prosocline, round, its lip slightly angulated. Umbilicus large. Animal with tip of snout elongated into finger-shaped processes, with long cephalic tenta¬cles, reduced neck lobes, but cephalic lappets are absent; the anterolateral processes of the foot are elongated and grooved. Three pairs of epipodial tentacles alongside operculum.
Minor spiral ridges run between the main ones, most obviously on the base of the shell. Most spiral ridges are tuberculated by the numerous costae. These cross the whorls of the spire but on the last whorl usually end about level with the most adapical spiral; between the suture and that spiral the profile is flat and at right angles to the shell axis (producing the stepped profile) whilst between that spiral and the periphery the profile is flat or concave, below that, on the last whorl, convex. Up to 8 mm high, 8 mm broad; last whorl occupies 70-75% of shell height, aperture 40%.
The snout is depressed and broad, the cephalic tentacles not setose. The eyes are small, the left neck lobe forms a short tentacle, the right a small scroll fastened to the eye stalk. The foot is large and broad anteriorly, without epipodial sense organs (Fretter & Graham, 1977), Cream with brown on the sides of the foot.

S. amabilis has been recorded only a few times off the British Isles - off Shetland and in the Celtic Sea. It is widespread in the north east Atlantic, dredged from sandy or gravelly bottoms from 150 to over 1000 m deep. Its way of life is unknown: in view of its modified structure it deserves investigation. Females lay a few large yolky eggs surrounded by jelly; there is probably no free larval stage.