''Clanculus kraussii'' 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

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 ...

Trochidae The Trochidae, common name top-snails or top-shells, are a family of various sized sea snails, marine gastropod molluscs in the subclass Vetigastropoda. This family is commonly known as the top-snails because in many species the shell resembles ...

, the top snails.Gofas, S. (2014). Clanculus kraussii (Philippi, 1846). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=180884 on 2014-04-29 There is also a homonym ''Clanculus kraussi'' (non-Philippi) Sowerby, 1897, a synonym of '' Clanculus atricatena'' J.R. Tomlin, 1921

Description

The size of the shell varies between 9 mm and 23 mm. The umbilicate, moderately thick shell has a conoid shape. The five convex

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 are separated by canaliculate sutures. The first whorls are eroded, whitish, the rest roseus, cinereous or brownish, ornamented with a few radiating white streaks. They are spirally granose-lirate with 6 finely beaded lirae on the penultimate whorl, the fifth larger, more prominent, simulating a carina. 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 ...

is angulate, plano-convex beneath and concentrically cingulate. The about 7 cinguli are granose with the interstices sometimes bearing concentric lirulae. 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 rhomboidal. The lip within is thickened and sulcate. The basal margin is crenulate. The columella is tuberculose, above twisted plicate, below obsoletely truncate. The white umbilical area is spirally plicate with a crenulate margin. The thin parietal callus is wrinkled.H. Pilsbry, Manual of Conchology XI, Academy of Natural Sciences, Philadelphia
(described as ''Trochus kraussi'' )

Distribution

This marine species occurs in the Atlantic Ocean from

Morocco Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to ...

Angola , national_anthem = " Angola Avante"() , image_map = , map_caption = , capital = Luanda , religion = , religion_year = 2020 , religion_ref = , coordina ...

References

Zeitschrift für Malakozoologie (1844–1848), vol. 1846 p. 100
* Pallary P., 1920: ''Exploration scientifique du Maroc organisée par la Société de Géographie de Paris et continuée par la Société des Sciences Naturelles du Maroc.''; Deuxième fascicule. Malacologie (1912) Larose, Rabat et Paris pp. 108, 1 pl., 1 map

External links

* {{DEFAULTSORT:Clanculus Kraussii kraussii Gastropods described in 1846 Taxa named by Rodolfo Amando Philippi