''Pleurotomella imitator'' 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

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 ...

mollusk in the family

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). . 39 ...

Description

The length of the shell attains 3 mm, its diameter 1.5 mm. (Original description) The minute, white shell has a sinusigera

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 ...

consisting of 2½

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 and followed by nearly four subsequent whorl. The suture is distinct and appressed. The whorls are only moderately convex. The axial sculpture consists of (on the

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 ...

about 14) narrow, oblique ribs with wider interspaces, crossing the whorls, stronger on the earlier whorls, and ending in small close beadlike pustules in front of the suture. These ribs become obsolete on the base. The spiral sculpture consists of a single carina near the periphery of the whorls, prominent where it intersects the ribs, and 10 or 12 fine threads in front of the carina which slightly cut the ribs in crossing them. The anal fasciole is wide, extending from the carina to the coronation of the suture. The base is moderately convex. The columella is short, smooth and obliquely truncate. The outer lip is thin and sharp. 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 is dr ...

is wide and short. Dall, William Healey. "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 (1927)

Distribution

This species occurs in the Atlantic Ocean off Georgia, USA.

References

External links

*
Gastropods.com: ''Pleurotomella imitator''
{{DEFAULTSORT:Pleurotomella Imitator imitator Taxa named by William Healey Dall Gastropods described in 1927