Shell large tor the genus, thin, subglobose, flattened above. Colour cream. Whorls three, rapidly increasing. Earlier whorls wound in the same plane, the last steeply descending, sharply angled at the fasciole,compressed and then inflated beneath it. Umbilicus moderate in width, deep, with smooth walls. Sculpture : both above and below the fasciole the shell is ornamented by about twentytwo prominent longitudinal ribs, which project most beneath the fasciole half a whorl behind the mouth, from thence on they diminish considerably. These are overridden by close, sharp, raised, spiral lines, which cross the interstices and denticulate the crests of the ribs. Slit pointed anteriorly, rounded posteriorly, in length about a sixth of the circumference of the shell. The fasciole, a broad gutter with raised margins, its trough septate by continuations of the longitudinal ribs, ascends the spire for a whorl and a half, as in other Pacific species. Aperture ovate, columella slightly reflected. Major diameter 2,3, minor 1,7; height 2 mm.
Dredged off Beacon Islet (Funamanu), in 150 fathoms, and off Tutaga in 150 and 50-60 fathoms.

This species stands nearest to S. ferriezi, Crosse, from which it is clearly distinguished by a more elevated spire, coarser sculpture and larger size.