Shell small to large, turbinate, thick, heavy, nacreous inside; labial margin at least slightly prosocline; the columellar callus covers the umbilicus. Sculpture mainly spiral, with or without knobs or spines at the periphery. Operculum calcareous, with a horny layer inside.
Bolma Risso, 1826:
On the last whorl, presence of one or two angulations bearing some radial sculpture. Spiral sculpture well marked on the whole surface.
