''Leucosyrinx exulans'' 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 ...

Pseudomelatomidae Pseudomelatomidae is a family (biology), family of predatory sea snails, marine gastropods included in the superfamily Conoidea (previously Conacea) and part of the Neogastropoda (Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005), Bouchet & Ro ...

, the turrids and allies.

Description

The length of the shell attains 32 mm, its diameter 13 mm. (Original description) The solid shell has a yellowish chocolate-brown color. It is strongly sculptured, with eight or nine

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. The tip is eroded in all the specimens. The whorls are rounded. The region of the fasciole in front of the closely appressed suture is flattish, constricted, and polished. The transverse sculpture in front of the fasciole (on the penultimate whorl) consists of about fourteen short, stout, obliquely set riblets, which coronate the whorl and do not reach the suture in front. The spiral sculpture consists of rather narrow shallow grooves, separating slightly raised flattish, rather wider, threads. The last are finest on the fasciole and somewhat coarser near 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 i ...

, but tolerably uniform over the entire surface. The notch is rather wide, not very deep, rounded, and halfway between the suture and the posterior ends of the peripheral riblets. 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 ...

is thin, simple and produced in the middle. The siphonal canal is rather well defined and not very long. The

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 ...

is obliquely trimmed off in front, of a creamy brown, with a thin polished glaze. The axis is not pervious. The siphonal canal is rather deep, flaring a little anteriorly. Dall, W.H. (1890) Scientific results of explorations by the U.S. Fish Commission Steamer Albatross. No. VII – Preliminary report on the collection of Mollusca and Brachiopoda obtained in 1887–88. Proceedings of the United States National Museum, 12, 219–362, pls. 5–14
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Description

Distribution

References

External links