''Calliostoma simplex'' is a

species In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...

of sea snail, a marine gastropod

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is es ...

in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Calliostomatidae Calliostomatidae is a family of sea snails within the superfamily Trochoidea and the clade Vetigastropoda.Gofas, S. (2013). Calliostomatidae. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdeta ...

. Some authors place this taxon in the subgenus ''Calliostoma (Fautor)''

Description

(Original description by M.M. Schepman) The height of the shell attains 17 mm. The imperforate shell has an elevated conical shape. It is, unicoloured, and yellowish. The 7½

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 flo ...

s are slightly convex, with spiral lirae, increasing from 2 on the upper body whorl, to 6 on the penultimate and 7 on the upper surface of the ultimate one. The suture is not deep but distinct, accompanied by the upper part of a nearly covered spiral. The spirals are closely beset with compressed beads. The upper row of each whorl is slightly the largest. The body whorl is angular, keeled by the last spiral. The base of the shell is nearly flat, with 10 conspicuous, beaded spirals and a few very thin ones near the

aperture In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and focal length of an optical system determine the cone angle of a bundle of rays that come to a focus in the image plane. An ...

. Moreover, the whole shell is covered with oblique, undulating, slightly laminar, radiating striae, very distinct on the base. The aperture is subquadrate. The outer margin is thin, a little convex, with 5 spiral grooves. The basal margin is convex. The

columella Lucius Junius Moderatus Columella (; Arabic: , 4 – ) was a prominent writer on agriculture in the Roman Empire. His ' in twelve volumes has been completely preserved and forms an important source on Roman agriculture, together with the ...

is cylindrical, slightly concave, patulous but not toothed at the base, interiorly ending in a flat layer of nacre, running over the basal margin.Schepman 1908–1913, The Prosobranchia of the Siboga Expedition; Leyden, E. J. Brill, 1908–13
/ref>

Distribution

This marine species occurs off

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...

and the

Philippines The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

References

External links

* {{DEFAULTSORT:Calliostoma Simplex

simplex In geometry, a simplex (plural: simplexes or simplices) is a generalization of the notion of a triangle or tetrahedron to arbitrary dimensions. The simplex is so-named because it represents the simplest possible polytope in any given dimension ...

Gastropods described in 1908