''Sediliopsis aphanitoma'' is an extinct 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

Pseudomelatomidae Pseudomelatomidae is a family of predatory sea snails, marine gastropods included in the superfamily Conoidea (previously Conacea) and part of the Neogastropoda ( Bouchet & Rocroi, 2005). In 1995 Kantor elevated the subfamily Pseudomelatomina ...

, the turrids and allies.Dall, William Healey. "Contributions to the Tertiary fauna of Florida, with special reference to the Miocene Silexbeds of Tempa and the Pliocene beds of the Caloosahatchie River. Part 2, Streptodont and other gastropods, concluded." Wagner Free Institute of Science of Philadelphia, Transactions 3 (1892): 201-471
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Description

The length of the shell attains 21.5 mm, its diameter 8 mm. (Original description) The shell has a pointed, conical spire and large

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 ...

. The sculpture is obsolete on two smooth nuclear and eight later

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. 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 ...

is small and blunt. it is followed by a closely reticulated third whorl. The spiral sculpture is obscure. It consists of larger and smaller spirals, more or less alternated, but hardly interrupting the continuity of the surface, the most evident being a peripheral pair. The whorl is thickened in front of the appressed suture, and yet not distinctly to form a thread. The spirals are most distinct near the columella. The transverse sculpture consists of (about nine on the body whorl) well-marked, prominent ribs, extending on the early whorls from suture to suture, and rather wide incremental lines, sometimes pleated at the suture. The anal fasciole is not constricted, obscure, with a shallow notch. The columella is distinct, with a well-marked siphonal fasciole. Internally with a smooth enamel reflected over it. The aperture is narrow. 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 ...

is recurved and deeply notched. The outer lip is thin, arched, simple, varicose behind, smooth within.

Distribution

Fossils of this species were found in Pliocene Strata in Florida and North Carolina, USA.

References

External links

Don I. Tippett, ''Taxonomic notes on the western Atlantic Turridae (Gastropoda: Conoidea)''; the Nautilus v. 109 (1995-1996)
{{DEFAULTSORT:Sediliopsis Aphanitoma

aphanitoma ''Aphanitoma'' is a genus of sea snails, marine gastropod mollusks in the family Borsoniidae.Bouchet, P.; Gofas, S. (2015). Aphanitoma Bellardi, 1875. In: MolluscaBase (2015). Accessed through: World Register of Marine Species at http://www.marin ...

Gastropods described in 1892