''Pendroma perplexa'' 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 ...

Pendromidae Pendromidae is a family of 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 salt ...

.Rosenberg, G. (2012). ''Pendroma perplexa'' Dall, 1927. 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 specialist ...

at http://www.marinespecies.org/aphia.php?p=taxdetails&id=533258 on 2012-12-23

Description

The small, whitish shell grows to a length of 3 mm. It has a subturbinate shape with four rapidly enlarging

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). Whorls in nature File:Photograph and axial plane floral ...

s. The minute

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 ...

is smooth. The 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 ...

show an axial

sculpture Sculpture is the branch of the visual arts that operates in three dimensions. Sculpture is the three-dimensional art work which is physically presented in the dimensions of height, width and depth. It is one of the plastic arts. Durable sc ...

. The numerous, sharp plicae on these whorls have an irregular pattern. These become obsolete beyond the periphery on 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 ...

. The deep suture is not channeled. 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 subovate. The outer lip is sharp and flexuous, while the inner lip is thin and has a narrow

umbilical Umbilical may refer to: *Umbilical cable *Umbilical cord *Umbilical fold *Umbilical hernia *Umbilical notch *Umbilical vessels **Umbilical artery **Umbilical vein *Umbilical zone *The Umbilical Brothers, two Australian comedic performers, David a ...

chink behind it. This chink is continued by a shallow groove behind the inner lip. Dall W. H. (1927). ''Small shells from dredgings off the southeast coast of the United states by the United States Fisheries Steamer "Albatross", in 1885 and 1886,'' Proceedings of the United States National Museum, vol 70, 1927, p. 1-2
/ref>

Distribution

This marine species occurs from St Kitts, West Indies to

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

References

External links

To Biodiversity Heritage Library (2 publications)

To Encyclopedia of Life

To USNM Invertebrate Zoology Mollusca Collection

To World Register of Marine Species
{{Taxonbar, from=Q7162518 Pendromidae Gastropods described in 1927