''Mangelia dina'' 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 Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Mangeliidae Mangeliidae is a monophyletic family of small to medium-sized, predatory sea snails, marine gastropod mollusks in the superfamily Conoidea. Bouchet, P. (2011). Mangeliidae P. Fischer, 1883. In: MolluscaBase (2016). Accessed through: World Regis ...

.P. Bartsch (1915), Report on the Turton collection of South African marine mollusks, with additional notes on other South African shells contained in the United States National Museum; Bulletin of the United States National Museum v. 91 (1915)

Description

The length of the shell attains 6 mm, its diameter 2.4 mm. (Original description) The milk white shell contains 6

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 2½ whorls 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 ...

are dextral, forming a low apex. The first whorl is small and smooth, the second much larger, marked by very slender riblets and fine spiral lirations which increase in strength with the growth of the whorls. The subsequent whorls are very strongly shouldered at about one third of the distance between the sutures anterior to the summit. They are marked by strong, somewhat protractive axial ribs, of which 12 occur upon all but the penultimate whorl. Upon this there are 14. Intercostal spaces are about three times as wide as the ribs. In addition to the axial

sculpture Sculpture is the branch of the visual arts that operates in three dimensions. Sculpture is the three-dimensional art work which is physically presented in the dimensions of height, width and depth. It is one of the plastic arts. Durable sc ...

the whorls are marked by spiral lirations which are of two strengths. Four of the stronger cross the whorls between the periphery and the shoulder. Of these one is immediately above the suture and one at the angle of the shoulder, the other two divide the space between them into three unequal areas. The space between the peripheral and second strong liration is crossed by four slender subequal spiral threads; that between the second and third also by four, that between the third and fourth by five, of which the middle one is a little stronger than the rest. The space between the shoulder and the summit of the whorls is marked by about 20 slender, equal and equally spaced, spiral threads. The sutures are strongly marked. The periphery of 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 ...

is well rounded. The base of the shell is attenuated, marked by strong and fine lirations like the

spire A spire is a tall, slender, pointed structure on top of a roof of a building or tower, especially at the summit of church steeples. A spire may have a square, circular, or polygonal plan, with a roughly conical or pyramidal shape. Spires are ...

, those on the columellar portion being stronger than the rest. There are twelve strong threads having a somewhat variable number of finer threads between them. The entire surface of spire and base is also marked by fine lines of growth which give a pitted appearance to the spaces between the fine spiral fines in the intercostal spaces. All the spirals cross the axial ribs and the coarser ones render their junctions with the ribs slightly nodulose. The

aperture In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and focal length of an optical system determine the cone angle of a bundle of rays that come to a focus in the image plane. An opt ...

is of irregular shape. The outer lip is scythe-shaped, the border of the deep-rounded notch which is immediately below the summit representing the handle, the flattened surface of the strongly in-bent outer lip forming the blade; the surface of the latter is finely, spirally striated. The columellar wall is covered by a thin callus which extends upon the parietal wall.

Distribution

This marine species occurs off

Port Alfred A port is a maritime facility comprising one or more wharves or loading areas, where ships load and discharge cargo and passengers. Although usually situated on a sea coast or estuary, ports can also be found far inland, such as Ha ...

, South Africa.

References

Tucker, J.K. 2004 ''Catalog of recent and fossil turrids (Mollusca: Gastropoda)''. Zootaxa 682:1-1295.
{{Taxonbar, from=Q39091007

dina Dina ( ar, دينا, he, דִּינָה, also spelled Dinah, Dena, Deena) is a female given name. Women * Dina bint Abdul-Hamid (1929–2019), Queen consort of Jordan, first wife of King Hussein * Princess Dina Mired of Jordan (born 1965), Princ ...

Gastropods described in 1915