Xenophoridae, commonly called carrier shells, is a

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 ...

of medium-sized to large

sea snails 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 ...

, 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 e ...

s in the clade

Littorinimorpha Littorinimorpha is a large order of snails, gastropods, consisting primarily of sea snails (marine species), but also including some freshwater snails ( aquatic species) and land snails ( terrestrial species).Bouchet P. & Rocroi J.-P. (Ed.); Frý ...

. According to the taxonomy of the Gastropoda by Bouchet & Rocroi (2005) the family Xenophoridae has no subfamilies.

Distribution

The Xenophorids live on sand and mud bottoms of the continental shelves and the continental slopes of the subtropical and

tropical The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in the Southern Hemisphere at S. The tropics are also referred to ...

seas and range from very shallow water to depths of more than 1,400 meters.Kreipl, K. & Alf, A. (1999): ''Recent Xenophoridae''. 148 pp. incl. 28 color plts. ConchBooks, Hackenheim, .

Shell description

Xenophorids are unusual in that in many of the species the animal cements small stones or shells to the edge of the

shell Shell may refer to: Architecture and design * Shell (structure), a thin structure ** Concrete shell, a thin shell of concrete, usually with no interior columns or exterior buttresses ** Thin-shell structure Science Biology * Seashell, a hard o ...

as it grows, thus the shells of those species are sometimes humorously referred to as "shell-collecting shells". The genus name '' Xenophora'' comes from two ancient Greek words and means "bearing (or carrying) foreigners". The shells are small to rather large (diameter of base without attachments 19–160 mm; height of shell 21–100 mm), depressed to conical, with narrow to wide, simple to spinose peripheral edge or flange separating

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 a ...

from base.

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 ...

large, base broad, rather flattened, often umbilicate. Periostracum very thin or wanting. Protoconch depressed-conical, multispiral (in one species paucispiral).

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 ...

usually with foreign objects attached in spiral series to peripheral flange and, sometimes, remainder of dorsum, at least on early

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 ...

. Operculum horny, yellowish to brown, nucleus lateral, with simple growth lamellae, sometimes with conspicuous radial striae or hollow radial ribs.

Genera

Genera within the family Xenophoridae include: *'' Onustus'' Swainson, 1840 - synonyms: ''Trochotugurium'' Sacco, 1896; ''Tugurium'' Fischer in Kiener, 1879 *'' Stellaria'' Möller, 1832 - synonym: ''Haliphoebus'' Fischer in Kiener, 1879; ''Xenophora'' (''Stellaria'') Schmidt, 1832 *'' Xenophora'' Fischer von Waldheim, 1807WoRMS (2010). ''Xenophora'' Fischer von Waldheim, 1807. In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database
on 2010-08-07 Accessed through: World Register of Marine Species
/ref> - type genus

References

External links

{{Taxonbar, from=Q4053381