''Xanthodaphne translucida'' 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 ...

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). . 3 ...

.MolluscaBase (2018). Xanthodaphne translucida (Watson, 1881). Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=709378 on 2018-02-20

Description

The shell grows to a length of 10 mm. (Original description) Animal: The foot is fuscous olive, large, thick, square in front, pointed behind. The mantle is paler. The siphon is rather short. The head and the tentacles are pale. The eyes are large and black, on the upper outer side and at about a fourth of the length of the tentacles, which are rather solid, long, and cylindrical. Between these, and a little above them, is the large prominent expanded snout, with a large circular opening in front, round which the edge of the snout projects like a thick fleshy fringe. There are two unequal branchial plumes. The

radula The radula (, ; plural radulae or radulas) is an anatomical structure used by molluscs for feeding, sometimes compared to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food ...

consists of exceptionally minute, acicular, sharp-pointed, horny prickles. There is no operculum Shell. The shell is thin, horny, smooth, oval, with a tumid body whorl, a rather high, subscalar, small-pointed, round-whorled, shallow-sutured conical spire, and a tumid lop-sided base, pointed at the columella, but with scarcely any 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 — there are close-set fine hairlike lines of growth. Under the microscope a system of much finer regular striae is seen to cover the whole surface. Spirals — there are many fine, irregular, and unequal rounded striae, which faintly appear on the surface, but are distinct on the columella and front of the shell. Besides these, there are fine microscopic smooth scratches. The colour of the shell is white, with a faint tinge of yellow, horny, translucent, with a smooth and shining, but hardly glossy, surface. 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 rather high, conical, subscalar, from a slight bulge of the shoulder. The

protoconch A protoconch (meaning first or earliest or original shell) is an embryonic or larval shell which occurs in some classes of molluscs, e.g., the initial chamber of an ammonite or the larval shell of a gastropod. In older texts it is also calle ...

is small, conical, rounded, with the extreme tip flattened down. The six whorls are rounded, tumid, with a faint subangulation below the sinus-area, in which there is a flattening rather than a constriction of the surface. Below the periphery of each whorl the form is cylindrical, with a very slight contraction into the lower suture. The whorls increase regularly, but rapidly. The body whorl is large and tumid, with a protracted rounded base cut off on the left by an oblique, scarcely concave line. There is scarcely any snout, and the shell is truncated obliquely towards the point of the columella, which projects in a rectangular prominence. The suture is linear and 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 ...

is very large, lop-sidedly oval, pointed above and 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 ...

shows a semicircular curve in both planes, leaving a shallow, wide, shortly rounded sinus between the lip-edge and the body. The inner lip shows a thin, narrow pad stretched very regularly along its whole length (which forms a very regular concave curve) out to the thin, twisted, obliquely truncated edge of the columella. This edge runs out beyond the labial pad, and forms a thin sharp margin along the

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 ...

Distribution

This marine species occurs in the

Weddell Sea The Weddell Sea is part of the Southern Ocean and contains the Weddell Gyre. Its land boundaries are defined by the bay formed from the coasts of Coats Land and the Antarctic Peninsula. The easternmost point is Cape Norvegia at Princess Mar ...

, Antarctica; also off Kerguelen and

Crozet Island The Crozet Islands (french: Îles Crozet; or, officially, ''Archipel Crozet'') are a sub-Antarctic archipelago of small islands in the southern Indian Ocean. They form one of the five administrative districts of the French Southern and Antar ...

References

* Engl, W. (2012). Shells of Antarctica. Hackenheim: Conchbooks. 402 pp

External links

Kantor Y.I., Harasewych M.G. & Puillandre N. (2016). A critical review of Antarctic Conoidea (Neogastropoda). Molluscan Research. 36(3): 153-206

Griffiths, H.J.; Linse, K.; Crame, J.A. (2003). SOMBASE - Southern Ocean mollusc database: a tool for biogeographic analysis in diversity and evolution. Organisms Diversity and Evolution. 3: 207-213
* translucida Gastropods described in 1881 {{Raphitomidae-stub