''Calliotropis calcarata'' is a

species In biology, a species is the basic unit of 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 the appropriate s ...

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 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 e ...

in the

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

Eucyclidae Eucyclidae is a family of gastropods in the superfamily Seguenzioidea (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005). This family has no subfamilies. Genera Genera within the family Eucyclidae include: * '' Amberley ...

Description

The length of the shell reaches 11 mm. The shell has a depressedly conoidal shape. It is sharply keeled, with a flat base and large umbilicus. It is nacreous under a thin, transparent, yellowish-white layer. The 5½

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 are slightly convex, especially the

body whorl The body whorl is part of the morphology of the shell in those gastropod mollusks that possess a coiled shell. The term is also sometimes used in a similar way to describe the shell of a cephalopod mollusk. In gastropods In gastropods, the b ...

. The nucleus is smooth and shining. The

sculpture Sculpture is the branch of the visual arts that operates in three dimensions. Sculpture is the three-dimensional art work which is physically presented in the dimensions of height, width and depth. It is one of the plastic arts. Durable sc ...

consists on the upper whorls of rather distant, radiating ribs, crossed about halfway by a spiral rib or keel, forming small, sharp tubercles where they cross each other. On the third whorl, another series of tubercles appears, at some distance from the deep suture. On the penultimate whorl, the number of rows of tubercles amounts to three and the suture is conspicuously crenulated by the keel, which rests on the body whorl. This whorl is adorned by 5 spiral rows of tubercles, of which the second from above is the smallest. Moreover, the keel is surmounted by short, conical, rather sharp spines of which 38 are visible, if seen from below. The base of the shell is nearly flat, more convex towards 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 opt ...

, with 7 spiral rows of beads on rounded lirae, and a row of stronger ones, bordering the umbilicus. Moreover, the whole body whorl is covered with irregular radiating wrinkles or riblets, instead of the regular ribs on the upper whorls. These ribs are especially conspicuous and more regular on the base, except towards the periphery where they form thinner, irregular wrinkles. The umbilicus is pervious, funnel-shaped. Its walls has strong wrinkles. The

is rhombic. Its upper margin is regularly convex, not very thin, and thickened interiorly. It is separated from the basal margin by a groove, corresponding to the keel. The basal margin is convex, crenulated, thickened interiorly. The columellar margin is rather thick, concave in its upper part, and terminating in a sort of tooth below. The parietal wall is covered by a thick layer of enamel, thickened at its margin and connected to the columella by a broad, rounded tongue-shaped projection, covering part of the umbilicus, whose largest diameter, from the base of the columella to the opposite side, is about 2/5 of the diameter of the shell. The thin operculum is horny, many-whorled, and concave at the outer side. The

radula The radula (, ; plural radulae or radulas) is an anatomical structure used by molluscs for feeding, sometimes compared to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food ...

has the teeth in about 48 rows. The rhachidian tooth (R) has a rounded body, with crooked hooks at the angles of the very concave posterior margin, and is thickened by a plate of a triangular shape, with concave sides. The cusp is considerably narrower than the body, which is large in front. It has a sharp point and a few small denticles on each side; the body of the first lateral tooth is larger, subquadrate, with a sharply pointed cusp and a few smaller denticles The second one has a similar, but more elongated shape and a sharper cusp, also with a few smaller denticles. The third lateral is long and slender, strongly hooked, with denticles at the base of the cusp, and resembles more the uncini. Of the uncini the outer ones have a toothed margin, the outermost is broader with many small denticles.Schepman 1908-1913, The Prosobranchia of the Siboga Expedition; Leyden, E. J. Brill,1908-13
(described as ''Solerielopsis calcarata'')

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 ...

, 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 ...

and the

Solomon Islands Solomon Islands is an island country consisting of six major islands and over 900 smaller islands in Oceania, to the east of Papua New Guinea and north-west of Vanuatu. It has a land area of , and a population of approx. 700,000. Its capita ...

References

* Vilvens C. (2007) ''New records and new species of Calliotropis from Indo-Pacific''. Novapex 8 (Hors Série 5): 1-72.

External links

* File:Calliotropis calcarata 002.jpg, apical view File:Calliotropis calcarata 003.jpg, basal view {{Taxonbar, from=Q5022595 calcarata Gastropods described in 1908