Colpospira smithiana (Donald, 1900)
Description: Protoconch 2 whorls, teleoconch 12 whorls in adult shells. Whorls convex, suture impressed. Whorls spirally ribbed; latter whorls sculptured with 4 strong spiral keels, the one on the periphery usually strongest, and sometimes 1 or 2 threads. Axial sculpture of sparse growth lines conforming to shape of outer lip sinus. Inner lip of aperture reflected outwards at base; outer lip thin, with a deep sinus, lip usually broken. Base with 6 or 7 spiral threads. Colour uniformly white. Operculum circular, corneous..
Size: Up to 19 mm in length.
Distribution: Endemic to Australia: Cairns, Queensland, around southern Australia to south-western WA.
Habitat: Known from 274-1464 m. Common.
Comparison: This is a very deep water species, pure white with strong spiral keels. C. atkinsoni is larger, with only one strong keel. C. curialis is also white and from deep water, but has nodulose ribs. C. wollumbi and C. yarramundi are white shells with similar sculpture, but are less than half the size of C. smithiana.
Fig. 1: East of Cape Three Points, NSW, in 457-476 m (C.310022).
Copyright Des Beechey 2006