''Crenilabium exile'' is a

species In biology, a species is the basic unit of Taxonomy (biology), 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 ...

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 es ...

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 ...

Acteonidae Acteonidae, common name the "barrel bubble snails", is a family of small sea snails, marine gastropod mollusks of the informal group Lower Heterobranchia.Bouchet, P. (2012). Acteonidae. Accessed through: World Register of Marine Species at http ...

Description

The length of the shell varies between 6 mm and 11 mm. (Described as ''Acteon exilis'')The oblong or somewhat spindle-shaped shell is semitransparent and glossy. The

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 numerous spiral strisa or impressed lines, which are quite smooth or plain, instead of being punctate as in other species of this family. The color is clear white. 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 are ...

is elongated, with a blunt

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. There three moderately 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 flo ...

s. The body whorl occupies three-fourths of the spire. The first whorl is mammiform. The suture is distinct and margined. 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 rather narrow, irregularly pear-shaped and expanded at the base. Its length is three-fifths of the shell. The outer

lip The lips are the visible body part at the mouth of many animals, including humans. Lips are soft, movable, and serve as the opening for food intake and in the articulation of sound and speech. Human lips are a tactile sensory organ, and can be ...

is gently curved, and folds inwards. The inner lip is folded back on the lower part. The

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 ...

is flexuous. The fold in the columella is strong and conspicuous. G.W. Tryon, (1893) - Manual of conchology, structural and systematic : with illustrations of the species ser;1 vol. 15; Philadelphia, Published by the Author, Academy of Natural Sciences, 1879-1898

Distribution

This marine species has a wide distribution. It occurs off the Atlantic Ocean off USA (from Massachusetts to Florida); Iceland; Azores; Bay of Biscay; Portugal, West Africa; Mediterranean Sea off Spain, Malta, Italy; in the Caribbean Sea off East Mexico, Cuba, Costa Rica, Grenada, Martinique and Guadeloupe

References

* Abbott, R. T. (1974). American seashells. The marine Mollusca of the Atlantic and Pacific coast of North America. ed. 2. Van Nostrand, New York. 663 pp., 24 pls. * Rosenberg, G.; Moretzsohn, F.; García, E. F. (2009). Gastropoda (Mollusca) of the Gulf of Mexico, Pp. 579–699 in: Felder, D.L. and D.K. Camp (eds.), Gulf of Mexico–Origins, Waters, and Biota. Texas A&M Press, College Station, Texas

External links

Jeffreys J.G. (1870). Mediterranean Mollusca. Annals and Magazine of Natural History. ser. 4, 6: 65-86

ordan, H. K. (1895). On some new species of British Mollusca, from the "Triton" Expedition, with a list of other species new to the Faroe Channel. Proceedings of the Malacological Society of London. 1(6): 264-269, pl. 16

Bell, A. (1870). On some new or little-known shells &c. of the Crag Formations. The Annals and Magazine of Natural History. (4) 6: 213-217

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. 70(2667): 1-134

Verrill, A. E. (1882). Catalogue of marine Mollusca added to the fauna of the New England region, during the past ten years. Transactions of the Connecticut Academy of Arts and Sciences. 5(2): 447-587, pls 42-44, 57-58

Gofas, S.; Le Renard, J.; Bouchet, P. (2001). Mollusca. in: Costello, M.J. et al. (eds), European Register of Marine Species: a check-list of the marine species in Europe and a bibliography of guides to their identification. Patrimoines Naturels. 50: 180-213
{{Taxonbar, from=Q13501249 exile Gastropods described in 1870