As Roya devexa:
Shell small, white, much elevated, with a large, prominent spiral nucleus, which projects far forward over the posterior slope, and consists of three rapidly increasing whorls, smooth and shining. Adult shell smooth, but not shining, lamellated with growth lines, which are strongly developed on the anterior slope; there are faint indications of radial ridges near the base. It is possible the species reaches a much greater size, and that these radial would then develop into regular ribs. The base forms a narrow oval, rather pointed under the apex. There are the remains of a thin deciduous epidermis.
Height 5 mm Breadth, greatest 4 mm, least 3 mm.
Type, with five others (all smaller), from 50-70 fathoms, off Port Arthur, and an apical portion from 40 fathoms, off Schouten Island. This remarkable species seems most nearly related to C. violacea, Angas.