''Ophiodermella inermis'' is a species of

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 ...

Borsoniidae Borsoniidae is a monophyletic family of small to medium-sized sea snails, marine gastropod mollusks in the superfamily Conoidea.Bouchet, P. (2011). Borsoniidae. Accessed through: World Register of Marine Species at http://www.marinespecies.org/ ...

Description

The shell grows to a length of 40 mm, its width 7 mm. The shell is pinkish ash-colored under a light olivaceous epidermis. The lines of growth are sometimes rib-like, oblique and angulated at the periphery and lighter-colored, so that the interspaces appear like angulated lines of chestnut or reddish narrow stripes. The whole surface is covered by close revolving incised lines. The small shell is slender and very acute. Its color is of a livid purple. The shell is covered with an olivaceous periostracum, with about eleven

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 protoconch is more or less eroded, but apparently smooth, acute, and including about two and a half whorls. The subsequent whorls are rather flat, compressed and appressed at and in front of the suture, with a rounded base and inconspicuous anal fasciole. 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 chiefly of flattish spiral threads, one at the suture, three smaller ones in front of it, followed by a flat broader one representing the fasciole, then (on the

body whorl The body whorl is part of the morphology (biology), morphology of the gastropod shell, shell in those gastropod mollusks that possess a coiled shell. The term is also sometimes used in a similar way to describe the shell of a cephalopod mollusk ...

eight) more prominent threads, undulate or segmented by incremental lines and with wider interspaces (sometimes containing an intercalary smaller thread) to the base, followed by six or seven unsegmented threads to the siphonal fasciole, which bears six or seven smaller threads. The succession of undulations or slightly swollen segments gives a slightly cancellate effect to the part of the whorl which bears them, but there are no axial ribs, the effect being produced rather by depressions between the rather coarse incremental lines. 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 narrow and acute behind. The anal sulcus is narrow and distinct but not very deep. 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 ...

in front of it is arcuately produced. The siphonal canal is contracted, short, and recurved. Theis inner lip polished and superficially erased. The columellla is twisted, with a thin layer of callus. An operculum is present. W.H. Dall, .Descriptions of new species of mollusks from the Pacific coast of the United States; Proceedings of the United States National Museum v.34 1908
(described as ''Turris (Surcula) halcyonis'')

Distribution

This species occurs in the Pacific Ocean from

Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

References

* Carpenter, Proc. Acad. Nat. Sci. Phila. for 1865, p. 63, 1865 * Dall, Proc. U. S. Nat. Mus., vol. 34, No. 1610, p. 248, 16 June 1908. * McLean J.H. (1996). The Prosobranchia. In: Taxonomic Atlas of the Benthic Fauna of the Santa Maria Basin and Western Santa Barbara Channel. The Mollusca Part 2 – The Gastropoda. Santa Barbara Museum of Natural History. volume 9: 1-160

External links

*
Bartsch, P, Some turrid mollusks of Monterey Bay and vicinity; Proceedings of the Biological Society of Washington, v. 57 p. 57-68
{{DEFAULTSORT:Ophiodermella Inermis inermis Gastropods described in 1843