''Famelica monoceros'' 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 ...

Raphitomidae Raphitomidae is a family of small to medium-sized sea snails, marine gastropod mollusks in the superfamily Conoidea.Bouchet P. & Rocroi J.-P. (Ed.) (2005). "Classification and nomenclator of gastropod families". ''Malacologia'' 47(1-2). . 39 ...

Description

The length of the shell attains 4.6 mm. The thin, ivory-white, high, narrow shell is drawn out, with fine spiral threads, a very oblique impressed suture, rounded whorls, and a contracted base produced into a longish snout.

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 ...

. Longitudinals—none but fine, somewhat unequal lines of growth. Spirals—with the exception of the sinus-area, the whole surface is covered by fine, rounded, unequal, and irregularly interrupted spiral threads with rather broader intervals. The colour is porcellaneous, ivory-white, glossy. 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 remarkably narrow, high, drawn out and conical. The

apex The apex is the highest point of something. The word may also refer to: Arts and media Fictional entities * Apex (comics), a teenaged super villainess in the Marvel Universe * Ape-X, a super-intelligent ape in the Squadron Supreme universe *Apex ...

is broken. There are five

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 remaining, but probably 8–9 in all, of very regular, but rather rapid increase, high, oblique, slightly tumid. The body whorl is rounded, with a conical, protracted, but very lop-sided base running out into a longish straight

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 ...

and triangular snout. The suture is very oblique and rather deeply impressed. 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 pear-shaped, scarcely pointed above, and protracted into a gradually narrowing

siphonal canal The siphonal canal is an anatomical feature of the shells of certain groups of sea snails within the clade Neogastropoda. Some sea marine gastropods have a soft tubular anterior extension of the mantle called a siphon through which water is ...

below. 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 ...

has a very regular curve in both its planes. The outer edge has a very high and prominent shoulder, whose upper side runs a long way parallel to the body whorl above it, having a very deep rather than narrow sinus, between which and the body whorl is no shelf whatever. The inner lip is on the narrow body scarcely perceptible as a glaze. On the long direct twisted columella it is a little thicker, but is very narrow : the end of the columella is cut off with a very long-drawn, oblique, slowly narrowing, sharp, twisted edge.Watson, R.B. (1881). ''Mollusca of H.M.S. Challenger Expedition. Parts VIII, IX, X''. Journal of the Linnean Society, Zoology. 15: 388-475
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Distribution

This marine shell occurs off

Sierra Leone Sierra Leone,)]. officially the Republic of Sierra Leone, is a country on the southwest coast of West Africa. It is bordered by Liberia to the southeast and Guinea surrounds the northern half of the nation. Covering a total area of , Sierra ...

and Georgia (U.S. state), Georgia, USA

References

* 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. * Bouchet, P.; Warén, A. (1980). Revision of the North-East Atlantic bathyal and abyssal Turridae (Mollusca: Gastropoda). Journal of Molluscan Studies. Suppl. 8: 1-119

External links

*
Gastropods.com: ''Famelica monoceros''

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(18): 1-134
{{DEFAULTSORT:Famelica Monoceros

monoceros Monoceros (Greek: Μονόκερως, "unicorn") is a faint constellation on the celestial equator. Its definition is attributed to the 17th-century Dutch cartographer Petrus Plancius. It is bordered by Orion to the west, Gemini to the north, ...

Gastropods described in 1881