''Famelica monoceros'' is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

sea snail Sea snails are slow-moving marine (ocean), marine gastropod Mollusca, molluscs, usually with visible external shells, such as whelk or abalone. They share the Taxonomic classification, taxonomic class Gastropoda with slugs, which are distinguishe ...

, a marine

gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...

mollusk Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Raphitomidae Raphitomidae is a Family (biology), family of small to medium-sized sea snails, marine (ocean), marine gastropod mollusks in the superfamily Conoidea.Bouchet P. & Rocroi J.-P. (Ed.) (2005). "Classification and nomenclator of gastropod families" ...

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. Spire ...

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-Bomb Abomination Absorbing Man Abraxas Abyss Abyss is the name of two characters appearing in Ameri ...

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). In nature File:Photograph and axial plane floral diagra ...

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: ) was a prominent Roman writer on agriculture in the Roman Empire. His in twelve volumes has been completely preserved and forms an important source on Roman agriculture and ancient Roman cuisin ...

and triangular snout. The suture is very oblique and rather deeply impressed. The

aperture In optics, the aperture of an optical system (including a system consisting of a single lens) is the hole or opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image o ...

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 i ...

below. The outer

lip The lips are a horizontal pair of soft appendages attached to the jaws and are the most visible part of the mouth of many animals, including humans. Mammal lips are soft, movable and serve to facilitate the ingestion of food (e.g. sucklin ...

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
/ref>

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 to the southeast by Liberia and by Guinea to the north. Sierra Leone's land area is . It has a tropical climate and envi ...

and

Georgia Georgia most commonly refers to: * Georgia (country), a country in the South Caucasus * Georgia (U.S. state), a state in the southeastern United States Georgia may also refer to: People and fictional characters * Georgia (name), a list of pe ...

, 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: , "unicorn") is a faint constellation on the celestial equator. Its definition is attributed to the 17th-century cartographer Petrus Plancius. It is bordered by Orion to the west, Gemini to the north, Canis Major to the s ...

Gastropods described in 1881