''Austrocochlea diminuta'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

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 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 ...

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 ...

Trochidae The Trochidae, common name top-snails or top-shells, are a family of various sized sea snails, marine gastropod molluscs in the subclass Vetigastropoda. This family is commonly known as the top-snails because in many species the shell resembles ...

, the top snails.Bouchet, P. (2012). ''Austrocochlea diminuta'' (Hedley, 1912). Accessed through:

World Register of Marine Species The World Register of Marine Species (WoRMS) is a taxonomic database that aims to provide an authoritative and comprehensive list of names of marine organisms. Content The content of the registry is edited and maintained by scientific specialist ...

at http://www.marinespecies.org/aphia.php?p=taxdetails&id=546940 on 2012-11-23

Description

(Original description by Charles Hedley) The height of the shell attains 7 mm, its diameter also 7 mm. The small, solid shell has an ovate-turbinate shape. It is dull and rough. The 5½

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 are separated by impressed sutures. The colour of the shell is very variable: entire maroon or entire slate or either with broad radiating stripes of buff, or the spiials articulated with buff on a maroon or slate ground, or combinations of these. The nacre of the interior 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 ...

is bordered with emerald.

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 shell contains elevated spiral ridges, four or five on the upper whorls, about sixteen on the last, andsmaller and closer on the base. Both ridges and interstices are obliquely crossed by fine growth striae. The aperture is subquadrate, brilliantly nacreous with a narrow border. The base of the columella is externally expanded, internally bearing three small tubercles. The throat contains about seven entering ridges which commence at the bevel within the lip. 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 a slight smear of callus. Hedley, C. 1912. Descriptions of some new or noteworthy shells in the Australian Museum. Records of the Australian Museum 8: 131-160
(described as ''Monodonta diminuta'')

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

Northern Territory The Northern Territory (commonly abbreviated as NT; formally the Northern Territory of Australia) is an states and territories of Australia, Australian territory in the central and central northern regions of Australia. The Northern Territory ...

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_ ...

and

Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...

References

* Adams, A. 1853. ''Contributions towards a monograph of the Trochidae, a family of gastropodous Mollusca''. Proceedings of the Zoological Society of London 1851(19): 150-192 * Hedley, C. 1913. ''Studies of Australian Mollusca. Part XI''. Proceedings of the Linnean Society of New South Wales 38: 258-339 * Hedley, C. 1918. ''Narrative of an expedition of exploration in North Western Australia by Herbert Basedow. Special Report. Mollusca.'' Transactions of the Royal Geographical Society of Australasia, South Australian Branch 18: 263-283

External links

Barcode of Life (1 barcode)

Encyclopedia of Life

GenBank (5 nucleotides; 2 proteins)

World Register of Marine Species
{{Taxonbar, from=Q4825614 diminuta Gastropods of Australia Gastropods described in 1912