''Asperdaphne perissa'' 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 ...

Raphitomidae Raphitomidae is a Family (biology), family of small to medium-sized sea snails, marine (ocean), marine gastropod mollusks in the superfamily Conoidea.Bouchet P. & Rocroi J.-P. (Ed.) (2005). "Classification and nomenclator of gastropod families" ...

Description

The length of the shell attains 7.4 mm, its diameter 2.9 mm. (Original description) The thin shell is ovate-fusiform and has an acuminate

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 ...

. it contains five

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 of which two in 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 " ...

, the latter subulate with spiral punctate grooves. The colour of the shell is dead white except a cinnamon protoconch. The sculpture shows spiral threads predominating, amounting on 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 ...

to about thirty, not impinging on a broad anal fasciole, beneath this strong and widely spaced, becoming feebler and closer below the periphery, but waxing stronger on the back of 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 ...

. The penultimate carries six such spirals, then three, then two on the earlier whorls. The radials are stronger on the younger whorls, but decrease on the older. In the body whorl they fade away about the periphery, and in the penultimate scarcely reach across the whorl. In every case they are overridden by the spirals. 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 elliptical. The inner

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 overlaid by a substantial callus which, opposite the sulcus and at the base of the siphonal canal, is provided by a small but sharp tubercle. The outer lip is produced externally into a prominent

varix A varix (: varices) is an abnormally dilated blood vessel with a tortuous course. Varices usually occur in the venous system, but may also occur in arterial or lymphatic vessels. Examples of varices include: * Varicose veins, large tortuous veins ...

, and beset within by a row of small tubercles. The siphonal canal is short and broad. Ch. Hedley (1909), Mollusca from the Hope Islands, north Queensland; Proceedings of the Linnean Society of New South Wales v. 34 p. 458

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

Queensland Queensland ( , commonly abbreviated as Qld) is a States and territories of Australia, state in northeastern Australia, and is the second-largest and third-most populous state in Australia. It is bordered by the Northern Territory, South Austr ...

References

* Hedley, C. 1909. ''Mollusca from the Hope Islands, north Queensland''. Proceedings of the Linnean Society of New South Wales 34(1): 420–466, pls 36–44 * Li B.-Q. aoquan& Li X.-Z. inzheng(2014) ''Report on the Raphitomidae Bellardi, 1875 (Mollusca: Gastropoda: Conoidea) from the China Seas.'' Journal of Natural History 48(17-18): 999-1025

External links

Hedley, C. 1922. A revision of the Australian Turridae. Records of the Australian Museum 13(6): 213-359, pls 42-56
* {{DEFAULTSORT:Asperdaphne Perissa perissa Gastropods described in 1909 Gastropods of Australia