''Calliostoma fragum'' is a species of

sea snail Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the ...

, a marine

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusk in the family Calliostomatidae.

Description

The height of the shell attains 8 mm. The subperforate shell has a conical shape. It is pale purplish-brown, painted with whitish stripes, with 4 distant series of granules. The eight granulate

whorl A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). Whorls in nature File:Photograph and axial plane floral ...

s have their basal margins prominent. The interstices are very delicately obliquely striate. The base is a little convex, sculptured with 8 flat subgranose concentric lirae, each one divided by a furrow into two parts, alternating with narrow elevated lines. The smooth aperture is rhomboidal. The columella is a little oblique, and subtruncate at its base.Tryon (1889), Manual of Conchology XI, Academy of Natural Sciences, Philadelphia
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Distribution

This marine species occurs off the Philippines.

References

External links

* {{DEFAULTSORT:Calliostoma Fragum

fragum Fragum is a genus of cockles, marine bivalve molluscs in the family Cardiidae. Members of the genus have characteristic thick, sculptured shells and live buried in sand, extending their siphons to the surface to feed and breathe. They are found ...

Gastropods described in 1848 Taxa named by Rodolfo Amando Philippi