''Clionella rosaria'' 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 ...

Clavatulidae Clavatulidae is a taxonomic family of sea snails, marine gastropod mollusks in the superfamily Conoidea. The family is not well differentiated morphologically. Clavatulidae was raised, based on cladistic analysis, from subfamily to the family ...

. The forma ''Clionella rosaria'' f. ''kowiensis'' (Turton, 1932) is accepted as ''Clionella rosaria'' (Reeve, 1846)

Description

The size of an adult shell varies between 15 mm and 23 mm. The shell is shortly subulate, truncated at the base. The

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 d ...

are plaited and smooth. 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 short. The color of the shell is bright scarlet-rose, the uppermost part of the whorls is white-zoned. The shell has an elongate-conic shape. The nuclear

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 decollated. The post-nuclear whorls are moderately rounded, constricted at the sinus, which causes the summit of the turns to appear as a cord. The space between the sutures is variously mottled with flesh color and chestnut spots and streaks. The base, beginning at the periphery, is rose colored, a little paler on the columella than the rest. The whorls are marked with strong, protractive, axial ribs, which are about as wide as the spaces that separate them. Of these, 14 occur upon the first to sixth whorl, while 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 number increases to about 20. These ribs are interrupted at the sinus a little distance below the summit, and become decidedly enfeebled on the base, vanishing before they reach the columella. In addition to the axial ribs the surface is marked by numerous strong lines of growth. The spiral

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 ...

consists of equal and equally spaced spiral striations, which are about as broad as the spaces that separate them; these are best expressed in the groove of the sinus. The lirae, between the spiral striations and the axial lines of growth, inclose numerous small pits, giving the entire surface between the sutures the appearance of a grating. On the base the lines of growth are less strongly developed and the pittingis less pronounced. The

is rather short. The posterior angle is obtuse. The sinus is about as broad as the cord above it at the summit of the whorls. The space between the sinus and the anterior portion of the outer lip forms a claw-like element. The columella is strong, its inner edge, like the parietal wall, is glazed with a thin callus.P. Bartsch (1915), Report on the Turton collection of South African marine mollusks, with additional notes on other South African shells contained in the United States National Museum; Bulletin of the United States National Museum v. 91 (1915)
(described as ''Clionella sybaritica'')

Distribution

This marine species occurs from

False Bay False Bay (Afrikaans ''Valsbaai'') is a body of water in the Atlantic Ocean between the mountainous Cape Peninsula and the Hottentots Holland Mountains in the extreme south-west of South Africa. The mouth of the bay faces south and is demarcat ...

to South KwaZuluNatal, South Africa

References

* Kilburn, R.N. & Rippey, E. (1982) ''Sea Shells of Southern Africa''. Macmillan South Africa, Johannesburg, xi + 249 pp. page(s): 116 * Kilburn, R.N. (1985). ''Turridae (Mollusca: Gastropoda) of southern Africa and Mozambique. Part 2. Subfamily Clavatulinae''. Ann. Natal Mus. 26(2), 417–470 * Branch, G.M. et al. (2002). ''Two Oceans''. 5th impression. David Philip, Cate Town & Johannesburg * Steyn, D.G. & Lussi, M. (1998) ''Marine Shells of South Africa. An Illustrated Collector’s Guide to Beached Shells''. Ekogilde Publishers, Hartebeespoort, South Africa, ii + 264 pp. page(s): 150
Branch, G.M. et al. (2002). ''Two Oceans''. 5th impression. David Philip, Cate Town & Johannesburg

External links

* {{DEFAULTSORT:Clionella Rosaria Endemic fauna of South Africa rosaria Gastropods described in 1846