''Menestho exarata'' is a

species In biology, a species is the basic unit of Taxonomy (biology), 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 ...

of sea snail, a marine gastropod

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 es ...

in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Pyramidellidae Pyramidellidae, common name the pyram family, or pyramid shells, is a voluminous taxonomic family of mostly small and minute ectoparasitic sea snails, marine heterobranch gastropod molluscs. The great majority of species of pyrams are micr ...

, the pyrams and their allies.WoRMS (2011). ''Menestho exarata'' A. Adams, 1861. 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 speciali ...

at http://www.marinespecies.org/aphia.php?p=taxdetails&id=576642 on 2011-10-26Kantor Yu.I. & Sysoev A.V. (2006) Marine and brackish water Gastropoda of Russia and adjacent countries: an illustrated catalogue. Moscow: KMK Scientific Press. 372 pp. + 140 pls.

Description

The soiled white shell is elongate-conic. It measures 4.8 mm. The at least two whorls of 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 calle ...

are moderately large, helicoid, one-half obliquely immersed in the first volution of the

teleoconch The gastropod shell is part of the body of a gastropod or snail, a kind of mollusc. The shell is an exoskeleton, which protects from predators, mechanical damage, and dehydration, but also serves for muscle attachment and calcium storage. So ...

, the periphery projecting slightly beyond the left outline of 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. Spires are ...

. The six whorls of teleoconch are well rounded, very slightly shouldered. They are marked by faint lines of growth and well incised spiral lines, which are not all of the same strength nor are they equally spaced. Six of these appear upon the second, and seven upon the penultimate whorl between the sutures. The periphery and the base of the body whorl are well rounded, the latter sculptured like the space between the sutures, bearing six incised lines which are not quite as strong as those between the sutures. 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 ...

is oval, effuse at the junction of the outer lip and the

columella Lucius Junius Moderatus Columella (; Arabic: , 4 – ) was a prominent writer on agriculture in the Roman Empire. His ' in twelve volumes has been completely preserved and forms an important source on Roman agriculture, together with the ...

. The posterior angle is obtuse. The outer lip is thin, but opaque,. The columella is short, curved, somewhat revolute, reinforced by the attenuated base. The parietal wall is covered by a faint callus. Dall & Bartsch, ''Notes on Japanese, Indo-Pacific and American Pyramidellidae''; Proceedings of the U.S. National Museum, vol XXX n° 1452; 1906

Distribution

This marine species is found off Japan.

Habitat

This species is found in the following habitats: * Brackish * Marine

References

External links

World Register of Marine Species
{{Taxonbar, from=Q6816923 Pyramidellidae Gastropods described in 1861