''Odostomia stephensae'' is a species of

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 Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

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 ...

mollusc 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 esti ...

in the family Pyramidellidae, the pyrams and their allies.Rosenberg, G. (2011). ''Odostomia stephensae'' Dall & Bartsch, 1909. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=581255 on 2011-11-29 Dall & Bartsch used the epithet "stephensi", named after Katherine "Kate" Stephens (c. 1853-1954), curator at the Natural History Museum of San Diego. This museum considers this species a synonym of '' Odostomia tenuisculpta'' Carpenter, 1864Natural History Museum of San Diego
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Description

The bluish-white shell has an elongate-conic shape. Its length measures 5.3 mm. The

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 of 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 called ...

are almost completely obliquely immersed in the first of the succeeding turns, above which only the outer edge of the last volution projects. The six whorls of the teleoconch are rather high between the sutures, moderately rounded. They are ornamented by numerous fine but well incised subequal and subequally spaced spiral lines; about thirty-three of which appear between the summit and the periphery of the last whorl. The sutures are well marked. The periphery of

body whorl The body whorl is part of the morphology of the 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. In gastropods In gastropods, the b ...

is well rounded. The baseof the shell is rather prolonged, well rounded. Its entire surface is marked by incised spirals like the spaces between the sutures. In addition to the spiral markings, the entire surface shows fine incremental lines. The aperture is elongate-oval, effuse at the junction of the outer lip and the columella. The posterior angle is obtuse. The outer lip is thin. The columella is stout, curved, and decidedly reflected over the reinforced base. It is provided with a strong oblique fold opposite the obsolete umbilical chink. The parietal wall is covered with a thin callus.Dall & Bartsch, A Monograph of West American Pyramidellid Mollusks, United States National Museum Bulletin 68, 1p. 210-211; 1909 Plate 24 # 5
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Distribution

The type specimen was found off Baranoff Island, Alaska.

References

External links

World Register of Marine Species

ITIS
{{Taxonbar, from=Q3139497 stephensae Gastropods described in 1909