Asthelys antarctica

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Asthelys antarctica
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Clade: Vetigastropoda
Superfamily: Seguenzioidea
Family: Seguenziidae
Subfamily: Asthelysinae
Genus: Asthelys
Species:A. antarctica
Binomial name
Asthelys antarctica
Marshall, 1988

Asthelys antarctica is a species of extremely small deep water sea snail, a marine gastropod mollusk in the family Seguenziidae. [1]

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 sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. While these definitions may seem adequate, when looked at more closely they represent problematic species concepts. For example, the boundaries between closely related species become unclear with hybridisation, in a species complex of hundreds of similar microspecies, and in a ring species. Also, among organisms that reproduce only asexually, the concept of a reproductive species breaks down, and each clone is potentially a microspecies.

Sea snail common name for snails that normally live in saltwater

Sea snail is a common name for snails that normally live in salt water, in other words marine gastropods. The taxonomic class Gastropoda also includes snails that live in other habitats, such as land snails and freshwater snails. Many species of sea snails are edible and exploited as food sources by humans.

Family is one of the eight major hierarcical taxonomic ranks in Linnaean taxonomy; it is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae, but that family is commonly referred to as being the "walnut family".

Contents

Description

The shell attains a height of 5.8 mm.

Distribution

This species occurs in Antarctic waters off the South Shetland Islands at a depth of about 3700 m.

South Shetland Islands A group of islands north of the Antarctic Peninsula

The South Shetland Islands are a group of Antarctic islands with a total area of 3,687 square kilometres (1,424 sq mi). They lie about 120 kilometres (75 mi) north of the Antarctic Peninsula, and between 430 kilometres (270 mi) to 900 kilometres (560 mi) south-west from the nearest point of the South Orkney Islands. By the Antarctic Treaty of 1959, the islands' sovereignty is neither recognized nor disputed by the signatories and they are free for use by any signatory for non-military purposes.

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References

  1. Rosenberg, G. (2012). Asthelys antarctica. Retrieved through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=492407 on 2013-04-14