''Calliostoma zizyphinum'', common name the European painted top shell, 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 ...

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 e ...

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 ...

Calliostomatidae Calliostomatidae is a family of sea snails within the superfamily Trochoidea and the clade Vetigastropoda.Gofas, S. (2013). Calliostomatidae. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdeta ...

Description

The solid, regularly conical shell is straight-sided and imperforate. The shell contains up to 12–13 whorls. It is

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 ...

d with regular spiral grooves and ridges, traversed by fine prosocline growth lines. The

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is minute, composed of a single smooth rounded whorl, Several whorls follow, each with 4 granose spiral ridges. These become smooth and either obsolete or narrow on the later whorls. The body whorl has a prominent peripheral keel bearing two broad ridges; ridges above suture in preceding whorls. Base of shell rather flat, inner lips reflected over shallow umbilical groove. The periphery is angular, encircled by a smooth rounded rib that becomes a supra-sutural band or fasciole on 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 a ...

. The base of the shell is nearly flat. 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 quadrate. The cylindrical

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 nearly straight. The color of the shell is variable. The ground color is yellowish brown, pale pink, or violet with streaks and blotches of brown, red or purple on the periphery. Blotches on the keel are generally darker, more frequent and more regular than on other parts of shell. It is radiately clouded with brown on the upper surface. The base of the shell is unicolored or obscurely radiately streaked. Pure white or violet specimens are occasionally found.

Parasites

This species is host to the following parasites: * '' Trochicola entericus'' Dollfus, 1914 (

ectoparasitic Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson ha ...

copepod) * '' Endocheres obscurus'' Bocquet & Stock, 1956 ( ectoparasitic copepod) * '' Trochicola enterica'' Dollfus, 1914 (endoparasitic copepod)

Predators

The starfish ''

Asterias rubens The common starfish, common sea star or sugar starfish (''Asterias rubens'') is the most common and familiar starfish in the north-east Atlantic. Belonging to the family Asteriidae, it has five arms and usually grows to between 10–30 ...

'' is a known predator of ''Calliostoma zizyphinus'' A. Whilde, ''The Food of Starfish Asterias rubens L. on Cultivated and Derelict Oyster Fisheries'', The Irish Naturalists' Journal, Vol. 21, No. 12 (Oct., 1985), pp. 528–532
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Distribution

This marine species occurs in European waters from Northern

Norway Norway, officially the Kingdom of Norway, is a Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of Jan Mayen and the ...

to the

Azores ) , motto =( en, "Rather die free than subjected in peace") , anthem= ( en, "Anthem of the Azores") , image_map=Locator_map_of_Azores_in_EU.svg , map_alt=Location of the Azores within the European Union , map_caption=Location of the Azores wi ...

; in the

Mediterranean Sea The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the ...

References

* Backeljau, T. (1986). ''Lijst van de recente mariene mollusken van België ist of the recent marine molluscs of Belgium'' Koninklijk Belgisch Instituut voor Natuurwetenschappen: Brussels, Belgium. 106 pp. * Harms, J. , 1993. ''Checklist of species (algae, invertebrates and vertebrates) found in the vicinity of the island of Helgoland (North Sea, German Bight) - a review of recent records.'' Helgoländer Meeresuntersuch. 47 1: 1–34. * Gofas, S.; Le Renard, J.; Bouchet, P. (2001). Mollusca, in: Costello, M.J. et al. (Ed.) (2001). ''European register of marine species: a check-list of the marine species in Europe and a bibliography of guides to their identification.'' Collection Patrimoines Naturels, 50: pp. 180–213 * Muller, Y. (2004). ''Faune et flore du littoral du Nord, du Pas-de-Calais et de la Belgique: inventaire. oastal fauna and flora of the Nord, Pas-de-Calais and Belgium: inventory'' Commission Régionale de Biologie Région Nord Pas-de-Calais: France. 307 pp.

External links

Natural History Museum, London (NHM): Collections Management Database System
* {{DEFAULTSORT:Calliostoma Zizyphinum zizyphinum Gastropods described in 1758 Taxa named by Carl Linnaeus