''Awateria retiolata'' is an extinct species of

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 ...

Borsoniidae Borsoniidae is a monophyletic family of small to medium-sized sea snails, marine gastropod mollusks in the superfamily Conoidea.Bouchet, P. (2011). Borsoniidae. Accessed through: World Register of Marine Species at http://www.marinespecies.o ...

.Marshall, B. (2015). Awateria retiolata L. C. King, 1933 †. In: MolluscaBase (2015). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=831589 on 2016-02-11

Description

The length of the shell attains 10 mm, the width 4.5 mm. The spire is high, times the height of 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 ...

. The shell has whorls. The small, thin shel lhas a turreted shape. The

protoconch A protoconch (meaning first or earliest or original shell) is an embryonic or larval shell which occurs in some classes of molluscs, e.g., the initial chamber of an ammonite or the larval shell of a gastropod. In older texts it is also called ...

is worn. 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 of, on the spire-

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, of axial ribs reaching from the shoulder to the suture. The shell is inclined steeply to the left. The interspaces have the same width as the ribs. The whorls of the spire contain four spiral cords, the upper two the stronger, cross the axials below the shoulder, giving a reticulate sculpture to the spire. The shoulder is smooth and concave. 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 ...

has spiral sculpture only. The uppermost spiral cord on the shoulder angle is faintly nodulous on the earlier part of the body-whorl as a last suggestion of the previous axial sculpture. Weak growth-lines cover most of the shell, being rather more prominent on the smooth shoulder. The aperture is subquadrate, strongly channelled below and with a light sinus above. The columella is vertical, bent to the left below. The outer lip thin, the inner lip is well defined. King, L. C. "Tertiary molluscan faunas from the southern Wairarapa." Transactions of the New Zealand Institute. Vol. 63. 1933
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Distribution

This extinct marine species is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to New Zealand..

References

* Maxwell, P.A. (2009). ''Cenozoic Mollusca''. pp. 232–254 in Gordon, D.P. (ed.) New Zealand inventory of biodiversity. Volume one. Kingdom Animalia: Radiata, Lophotrochozoa, Deuterostomia. Canterbury University Press, Christchurch. {{DEFAULTSORT:Awateria Retiolata retiolata Gastropods described in 1933 Gastropods of New Zealand