''Agathotoma alcippe'' 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 Mangeliidae.

Description

The length of the shell varies between 5 mm and 11 mm. (Original description) The minute shell, which is either whitish or pale brownish, is subcylindrical and turreted in shape. 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 ...

features a projecting, minute subglobular apex and comprises about 1½ smooth

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. This is followed in the teleoconch by approximately 4½ sculptured whorls. The spiral sculpture consists of minute, close-set threads that uniformly cover the entire surface. The suture is distinct and appressed, with the whorls being shouldered immediately in front of it. The axial sculpture is characterized by prominent, slightly protractively oblique ribs (seven or eight 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 ...

), with wider interspaces. These ribs extend over the entire whorl and are prominent at the shoulder, but they are not continuous over the spire. The aperture is narrow, and the outer lip is varicose, thick, and striated in front while being smooth inside. The

anal sulcus The anal sulcus, also called the anal sinus or anal canal, in Gastropods is a notch, a shelly tube at the top of the aperture In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and fo ...

is conspicuous but not deep. The inner lip is smooth, and 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 barely differentiated.

Distribution

This marine species occurs off the Sea of Cortez, Western Mexico, and off Panama and the Galápagos Islands. Gbif.org: Agathotoma alcippe - occurrence
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References

External links

Bouchet P., Kantor Yu.I., Sysoev A. & Puillandre N. (2011) ''A new operational classification of the Conoidea''. Journal of Molluscan Studies 77: 273-308.

Tucker, J.K. 2004 ''Catalog of recent and fossil turrids (Mollusca: Gastropoda)''. Zootaxa 682:1-1295
* {{Taxonbar, from=Q4691564 alcippe Gastropods described in 1918