''Clypeostoma cancellatum'' is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

sea snail Sea snails are slow-moving marine (ocean), marine gastropod Mollusca, molluscs, usually with visible external shells, such as whelk or abalone. They share the Taxonomic classification, taxonomic class Gastropoda with slugs, which are distinguishe ...

, a marine

gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...

mollusc Mollusca is a phylum of protostome, protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant taxon, extant species of molluscs are recognized, making it the second-largest animal phylum ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Chilodontaidae Chilodontaidae is a taxonomic family of mostly small deepwater sea snails, marine gastropod molluscs in the clade Vetigastropoda (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005). Taxonomy The family was previously in ...

.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). In nature File:Photograph and axial plane floral diagra ...

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 (biology), morphology of the gastropod shell, 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 ...

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, the aperture of an optical system (including a system consisting of a single lens) is the hole or opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image o ...

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: ) was a prominent Roman writer on agriculture in the Roman Empire. His in twelve volumes has been completely preserved and forms an important source on Roman agriculture and ancient Roman cuisin ...

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 Indonesia–Timor-Leste border, divided between the sovereign states of Timor-Leste in the eastern part and Indonesia in the ...

, 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

Encyclopedia of Life

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