Clanculus johnstoni

Clanculus johnstoni
Original drawing showing two views of a shell of Clanculus johnstoni
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Clade: Vetigastropoda
Superfamily: Trochoidea
Family: Trochidae
Genus: Clanculus
Species: C. johnstoni
Binomial name
Clanculus johnstoni
Hedley, 1917

Clanculus johnstoni is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails.[1]

Description

The height of the shell attains 6 mm, its major diameter also 6 mm. The small, solid shell has a globose-conic shape. It has a carmine colour with radial buff dashes, about eight to a whorl, reaching from the suture half-way to the periphery. The umbilicus and the bordering funicle is white. As in allied forms, there is a colour dimorphism i nwhich olive brown replaces the carmine, a trace of which remains on the summit. The shell contains five whorls. On the penultimate whorl there are four spirals, the upper being a double bead row, and a fifth half-buried in the suture by the succeeding whorl. On the body whorl there are thirteen spirals which become taller, broader, more widely spaced and more inclined to break up into beads as they ascend from base to suture. The oblique aperture is finally ascending. Within the outer lip are about a dozen entering ridges, the lowest larger than the rest. The oblique columella is twisted, the edge reflected, with a large tooth at the base and a small one above. The umbilical margin broadly overreaches the cavity, its edge with three or four denticules. A translucent callus unites the lips.[2]

Distribution

This marine species is endemic to Australia and occurs at intertidal depths off the Northern Territory and Queensland

References

External identifiers for Clanculus johnstoni
WoRMS 594197
This article is issued from Wikipedia - version of the 4/29/2014. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.