''Mangelia orophoma'' 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 ...

.Melvill J.C. & Standen R. (1896) Notes on a collection of shells from Lifu and Uvea, Loyalty Islands, formed by the Rev. James and Mrs. Hadfield, with list of species. Part II. Journal of Conchology 8: 273–315

Description

The length of this very rare shell attains 3 mm, its diameter 1.25 mm. (Original description) This is a minute turreted pale brown species. The shell contains 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, angled just below the sutures, then straight. The straight longitudinal ribs, few in number, are crossed by lirae, conspicuous and large for the size of the shell, six at the penultimate whorl, nine 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 ...

, and less in proportion (e.g. four in the antepenultimate) on the other whorls. 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 narrow. The sinus is large and hollowing across the outer lip; which is somewhat thickened and obscurely toothed within.

Distribution

This marine species occurs off the Loyalty Islands and off

Mactan Island Mactan is a densely populated island located a few kilometers (~1 mile) east of Cebu#Cebu Island, Cebu Island in the Philippines. The island is part of Cebu province and it is divided into the city of Lapu-Lapu City, Lapu-Lapu and the municipal ...

, Philippines

References

External links

Tucker, J.K. 2004 ''Catalog of recent and fossil turrids (Mollusca: Gastropoda)''. Zootaxa 682:1–1295.
* {{DEFAULTSORT:Mangelia Orophoma orophoma Gastropods described in 1896