''Austrodrillia agrestis'' is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

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 ...

, a 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 ...

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 ...

Horaiclavidae Horaiclavidae is a family of predatory 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, taxonomi ...

. It was formerly included within the family

Turridae Turridae is a Taxonomy (biology), taxonomic family (biology), family name for a number of predatory sea snails, Marine (ocean), marine gastropod mollusks in the superfamily Conoidea.MolluscaBase (2018). Turridae H. Adams & A. Adams, 1853 (1838). ...

Description

The length of the attains 8.5 mm, its diameter 3 mm. The solid, rugged shell has an elongate-fusiform shape. It contains

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, including the protoconch of one whorl and a half, smooth, round, and blunt. The whorls on the

spire A spire is a tall, slender, pointed structure on top of a roof of a building or tower, especially at the summit of church steeples. A spire may have a square, circular, or polygonal plan, with a roughly conical or pyramidal shape. Spire ...

are sloping, scarcely concave in the upper part, convex in the lower. The suture is distinct, with a narrow adpressed margin. The

body whorl The body whorl is part of the morphology (biology), morphology of the gastropod shell, 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 ...

is concavely attenuated at the base. The

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 ...

is obliquely oval and shortly contracted posteriorly. The

siphonal canal The siphonal canal is an anatomical feature of the shells of certain groups of sea snails within the clade Neogastropoda. Some sea marine gastropods have a soft tubular anterior extension of the mantle called a siphon through which water i ...

is short, open and barely notched. The outer

lip The lips are a horizontal pair of soft appendages attached to the jaws and are the most visible part of the mouth of many animals, including humans. Mammal lips are soft, movable and serve to facilitate the ingestion of food (e.g. sucklin ...

is sharp, slightly ascending at the suture. The posterior sinus is deep, rather narrow, separated from the suture by a distance equal to its width, then convex, with an anterior shallow sinus at the base of the siphonal canal. The inner lip is inconspicuous, applied, smooth, with a callosity at its junction with the outer lip. The sculpture of the first two whorls is closely, regularly, validly, axially costulate, the rest rudely ribbed in the anterior two-thirds. The ribs are oblique, rounded, rather wider than the interspaces, becoming less marked and more distant on the

, and almost absent on the base, about 14 in the penultimate whorl. There are sublenticular accremental incisions. The spiral incisions ai'e deep, irregularly slightly wavy, about 8 in the penultimate whorl, and 20 in the body whorl, nearly equidistant, in places alternately fine and wide. The colour of the shell is uniform light-straw tint.Verco, J.C. 1909. ''Notes on South Australian marine Mollusca with descriptions of new species. Part XII.'' Transactions of the Royal Society of South Australia 33: 293–342
(described as ''Drillia agrestis'')

Distribution

This marine species is

endemic Endemism is the state of a species being found only 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 foun ...

to Australia and occurs off

South Australia South Australia (commonly abbreviated as SA) is a States and territories of Australia, state in the southern central part of Australia. With a total land area of , it is the fourth-largest of Australia's states and territories by area, which in ...

References

* Hedley, C. 1922. ''A revision of the Australian Turridae.'' Records of the Australian Museum 13(6): 213–359, pls 42–56 * Wells, F.E. 1990. ''Revision of the recent Australian Turridae referred to the genera Splendrillia and Austrodrillia''. Journal of the Malacological Society of Australasia 11: 73–117 * Wilson, B. 1994. ''Australian Marine Shells. Prosobranch Gastropods''. Kallaroo, WA : Odyssey Publishing Vol. 2 370 pp.

External links

Tucker, J.K. 2004 ''Catalog of recent and fossil turrids (Mollusca: Gastropoda)''. Zootaxa 682:1–1295
{{DEFAULTSORT:Austrodrillia Agrestis agrestis Gastropods of Australia