''Oenopota maurellei'' 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 (immature) shell attains 8.5 mm, its diameter 3.5 mm. (Original description) The small, fusiform shell is greenish white. it contains about six

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 first whorl 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 ...

is flattish, minute, apparently smooth. The second whorl shows a sharp prominent shoulder-keel, crossed by numerous minute riblets, much lower than the keel. On the next whorl the periphery bears a keel like that at the shoulder, and the riblets gradually become stronger, and fewer in number, diminishing, however, on the following whorls to mere axial striations. The peripheral keel also loses its prominence. On the later whorls, which still preserve—though with less prominence—the keel at the shoulder, the spiral sculpture becomes predominant. And on the spire there are about four spiral threads between the shoulder and the suture in front of it, and 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 ten between the shoulder and the beginning of 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 ...

, which is also spirally striated. The prominent shoulder gives a turreted aspect to the whorls.:The aperture is narrow. The outer lip is sharp. 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 shallow and feeble. The columella is white, and attenuate in front. The siphonal canal is short, and wide. The operculum is ovate, somewhat concave, and with an apical nucleus. Dall &

Bartsch Bartsch is a German surname. Notable people with the surname include: * Adam Bartsch (1757–1821), German scholar of old master prints and artist * Dietmar Bartsch (born 1958), German politician (Die Linke) * Jacob Bartsch (1600–1633), German as ...

, 1910," New Species of Shells", Canada Department of Mines, Geological Survey Branch, Memoir 14-N

Description

Distribution

References

External links