''Pleurotomella enora'' 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 9.5 mm, its diameter 4.2 mm. (Original description) The small shell is yellowish-white. It is decollate with 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 beside the (lost)

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 ...

. The spire is longer than the aperture. The suture is distinct, not appressed, with a broad anal fasciole in front of it, arcuately sculptured by lunate wrinkles following the lines of growth and in the earlier whorls elevated into sharp wrinkles at regular intervals, which are carried more or less distinctly over the anterior part of the whorls. In front of the somewhat concave fasciole the whorls are rounded and spirally sculptured with numerous close, very fine, sharp, spiral threads which cover the whorl, becoming coarser, less regular, and less crowded toward 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 ...

. The aperture is short and lunate. The outer lip shows a broad, deep, rounded

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 ...

close to the suture. The lip in front of it is thin, sharp, and strongly arcuately protractive. The body is smooth. The columella is very short, smooth, obliquely truncate. The siphonal canal is very short, deep, recurved, forming a marked siphonal fasciole. The operculum is absent. W.H. Dall (1908) Reports on the Mollusca and Brachiopoda, Bulletin of the Museum of Comparative Zoology at Harvard College. vol. 43

Description

Distribution

References

External links