''Asthelys'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

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 ...

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 ...

s 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 ...

Seguenziidae Seguenziidae is a family of very small deepwater sea snails, marine gastropod mollusks in the superfamily Seguenzioidea (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).Bouchet, P. (2012). Seguenziidae. Accessed through ...

Description

The conical shell lacks axial riblets and a peripheral carina but has a punctate microsculpture. The midwhorl angulation is initially absent, but present on later

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. The shell contains no spiral lirae. The U-shaped posterior sinus is shallow. The basal sinus is present, but there is no anterolateral sinus. The columella has no sinus or tooth. Tha

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 ...

has a rhomboidal shape. There is no umbilical septum.

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 ...

: the rachidian tooth is broader than high and has lateral wings prominent. The lateral tooth cusp is broad. There are less than 10 marginal tooth pairs.

Species

Species within the genus ''Asthelys'' include: * '' Asthelys antarctica'' Marshall, 1988 * '' Asthelys careyi'' Geiger, 2017 * '' Asthelys depressa'' Marshall, 1991 * '' Asthelys hyeresensis'' Hoffman, Gofas & Freiwald, 2020 * '' Asthelys munda'' (

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, 1879) * '' Asthelys nitidula'' Marshall, 1991 * '' Asthelys semiplicata'' Marshall, 1991 * '' Asthelys simplex'' (

, 1879)

References

* Marshall, B. A. (1988). ''New Seguenziidae (Mollusca: Gastropoda) from the Tasman, South Pacific, and Southern Antilles Basins''. New Zealand Journal of Zoology 15: 235-247 * Marshall B.A. (1991). ''Mollusca Gastropoda : Seguenziidae from New Caledonia and the Loyalty Islands''. In A. Crosnier & P. Bouchet (Eds) Résultats des campagnes Musorstom, vol. 7. Mémoires du Muséum National d'Histoire Naturelle, A, 150:41-109.

External links

Quinn J. (1987). ''A revision of the Seguenziacea Verrill, 1884. II. The new genera Hadroconus, Rotellenzia, and Asthelys''. Nautilus 101(2): 59-68
{{Taxonbar, from=Q4810830 Seguenziidae Gastropod genera