''Austroturris steira'' is a 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 ...

.WoRMS (2015). Austroturris steira (Hedley, 1922). In: MolluscaBase (2015). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=433092 on 9 February 2016

Description

The length of the shell attains 8 mm, its breadth 3.5 mm. (Original description) The small shell is solid and biconical. Its colour is uniform pale buff. The suture is channelled. It has seven

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 which two constitute 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 ...

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 ...

:—The dominant feature is a prominent peripheral keel revolving round all the whorls. The summit of each whorl is crowned by a double thread. Along the fasciole area run four slender threads. Between the keel and the anterior end of the shell occur about twenty cords, diminishing progressively as they recede from the periphery. Numerous crescentic threads cross the excavate fasciole. Fine radial lines also appear in the interstices of the basal spirals.

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 sinus is wide and deep, the canal short and open, a thin film of callus on the upper lip. Records of the Australian Museum 13 (1922)
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Distribution

This 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 Australia and occurs off

New South Wales ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es ...

References

* Hedley, C. 1922. A revision of the Australian Turridae. Records of the Australian Museum 13(6): 213–359, pls 42–56 * Laseron, C. 1954. ''Revision of the New South Wales Turridae (Mollusca)''. Australian Zoological Handbook. Sydney : Royal Zoological Society of New South Wales 1–56, pls 1–12. * Powell, A.W.B. 1967. ''The family Turridae in the Indo-Pacific. Part 1a. The Turrinae concluded.'' Indo-Pacific Mollusca 1(7): 409–443, pls 298–317 * Wilson, B. 1994. ''Australian Marine Shells. Prosobranch Gastropods.'' Kallaroo, WA : Odyssey Publishing Vol. 2 370 pp. {{DEFAULTSORT:Austroturris Steira steira Gastropods described in 1922 Gastropods of Australia