''Aartsenia martensi'' 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 ...

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 micromol ...

, the pyrams and their allies.Rosenberg, G. (2015). Aartsenia martensi (Dall & Bartsch, 1906). In: MolluscaBase (2015). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=740009 on 2015-12-16

Description

The ovoid shell is heavy and yellowish white. It measures 5.3 mm. The small

whorls 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 ...

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 called ...

are almost completely immersed in the first of the succeeding volutions. The five whorls 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. Some ...

are inflated and increase rapidly in size. They are subtabulately shouldered at the summit, marked by numerous fine lines of growth and equally abundant, loosely placed, wavy spiral striations. These lines of growth and spiral markings give the surface a finely reticulated appearance when viewed under high magnifications. The periphery and base of 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 ...

are decidedly rounded and inflated, marked like the space 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 opt ...

is large, suboval, slightly effuse anteriorly. The posterior angle is acute. The outer lip is sharp at the edge but thick within. 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 wo ...

is very strong, curved, reinforced by the body whorl, from which the slightly reflected edge is separated only by a narrow line. A strong oblique fold, not completely visible when the aperture is viewed squarely, is located a little anterior to the insertion of the columella. William Healy Dall and Paul Bartsch, "A Monograph of West American Pyramidellid Mollusks", Smithsonian Institution, 1909
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Distribution

The type species was found off

Killisnoo Killisnoo was an unincorporated community on Killisnoo Island in the Hoonah-Angoon Census Area in the U.S. state of Alaska, near Angoon which is on Admiralty Island. It is noted to have had a post office which closed in 1930. It has also been kno ...

, Alaska.

References

* Higo, S. & Goto, Y. (1993) ''A Systematic List of Molluscan Shells from the Japanese Is. and the Adjacent Area''. Elle Scientific Publications, Yao, Japan, xxii + 693 + 13 + 149 pp. page(s): 368

External links

To World Register of Marine Species
{{Taxonbar, from1=Q3171164 Pyramidellidae Gastropods described in 1906