''Asthelys'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

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 ...

s, 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 ...

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

s 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 ...

Seguenziidae Seguenziidae is a family (biology), family of very small deepwater sea snails, marine (ocean), marine gastropod mollusks in the superfamily Seguenzioidea (according to the Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005), taxonomy of the Gastr ...

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

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 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 ...

has no sinus or tooth. Tha

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 ...

has a rhomboidal shape. There is no umbilical septum.

Radula The radula (; : radulae or radulas) is an anatomical structure used by mollusks 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 enters ...

: 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 ''Asthelys antarctica'' is a species of extremely small deep water sea snail, a marine gastropod mollusk in the family Seguenziidae.Rosenberg, G. (2012). ''Asthelys antarctica''. Retrieved through: World Register of Marine Species at http://www ...

'' Marshall, 1988 * ''

Asthelys careyi ''Asthelys'' is a genus of sea snails, marine gastropod mollusks in the family Seguenziidae. Description The conical shell lacks axial riblets and a peripheral carina but has a punctate microsculpture. The midwhorl angulation is initially absen ...

'' Geiger, 2017 * ''

Asthelys depressa ''Asthelys depressa'' is a species of extremely small deep water sea snail, a marine gastropod mollusk in the family Seguenziidae.WoRMS (2012). ''Asthelys depressa''. Retrieved through: World Register of Marine Species at http://www.marinespeci ...

'' Marshall, 1991 * ''

Asthelys hyeresensis ''Asthelys'' is a genus of sea snails, marine (ocean), marine gastropod mollusks in the family (biology), family Seguenziidae. Description The conical shell lacks axial riblets and a peripheral carina but has a punctate microsculpture. The midwh ...

'' Hoffman, Gofas & Freiwald, 2020 * ''

Asthelys munda ''Asthelys munda'' is a species of sea snail, a marine gastropod mollusk in the family Seguenziidae. This species is spelled as ''Asthelys mundus'' in CLEMAM. Description (Original description by Watson) The height of the shell attains 3.3&nbs ...

'' ( Watson, 1879) * ''

Asthelys nitidula ''Asthelys nitidula'' is a species of extremely small deep water sea snail, a marine gastropod mollusk in the family Seguenziidae.WoRMS (2012). ''Asthelys nitidula''. Retrieved through: World Register of Marine Species at http://www.marinespeci ...

'' Marshall, 1991 * ''

Asthelys semiplicata ''Asthelys semiplicata'' is a species of extremely small deep water sea snail, a marine gastropod mollusk in the family Seguenziidae.WoRMS (2012). ''Asthelys semiplicata'' Marshall, 1991. Retrieved through: World Register of Marine Species at h ...

'' Marshall, 1991 * ''

Asthelys simplex ''Asthelys simplex'' is a species of extremely small deep water sea snail, a marine gastropod mollusk in the family Seguenziidae.Rosenberg, G. (2012). ''Asthelys simplex'' (Watson, 1879). Retrieved through: World Register of Marine Species at h ...

'' ( Watson, 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