''Clypeostoma cancellatum'' 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 Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

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 ...

Chilodontidae.MolluscaBase eds. (2021). MolluscaBase. Clypeostoma cancellatum (Schepman, 1908). Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=986595 on 2021-12-28

Description

(Original description by M.M. Schepman) The size of the shell varies between 7 mm and 12 mm. The elevated-conical, imperforate shell has convex sides. It is yellowish-white, with a nacreous lustre and numerous yellowish-brown spots, which are darker near the upper part of each

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 ...

and on the third whorl, the first and second being without markings. The nucleus is wanting, remaining five, slightly convex whorls with a narrow canaliculate suture. The first whorl has rather distant ribs. The next whorls have 3 spiral lirae (fine linear elevations) and radiating ribs. The last 3 whorls contain 5 spirals and thinner radiating ribs, which make the shell cancellated. These ribs become lamellose (with flared axial projections) on the lower whorls. The lirae are beaded where the ribs cross them, less obvious on the lower whorls, the uppermost of the lirae on each whorl with a series of small tubercles, giving a coronated appearance to the whorls. 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 ...

is rounded, the peripheral spiral being only very little prominent. The base of the shell is convex, with 6 beaded lirae, cancellated by numerous, irregular, radiating ribs. 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 ...

is nearly rounded. The outer and basal margins are rounded, thin, thickened interiorly, with about 17 short lirae on the internal rib, of which that near 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 wo ...

slightly tooth-like. The columella is cylindrical, rather straight, with a tooth-like fold at the base, bordering a rounded notch. The parietal wall is callous. The interior of the aperture has a few grooves.Schepman 1908-1913, The Prosobranchia of the Siboga Expedition; Leyden,E. J. Brill,1908-13
(described as ''Calliostoma (Perrinia) cancellatum'' )

Distribution

This marine species occurs off

Timor Timor is an island at the southern end of Maritime Southeast Asia, in the north of the Timor Sea. The island is East Timor–Indonesia border, divided between the sovereign states of East Timor on the eastern part and Indonesia on the western p ...

, Indonesia.

References

* Vilvens, C. (2017). New species and new records of Chilodontidae (Gastropoda: Vetigastropoda: Seguenzioidea) from the Pacific Ocean. Novapex, Hors Série. 11: 1-67

External links

To Encyclopedia of Life

To World Register of Marine Species
* {{Taxonbar, from2=Q14656927, from1=Q61700520 cancellatum Gastropods described in 1908