''Mangelia maoica'' is a minute extinct 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 ...

.Bulletins of American paleontology v. 5 no. 22-30 (1911-1917)

Description

The length of the shell attains 4 mm, its diameter 1.5 mm. (Original description) The small shell is turreted. 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 ...

contains 4

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, glassy, the last volution carinated and delicately longitudinally ribbed. The 4 subsequent whorls are strongly carinated in young shells but in the adult 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 ...

becomes gently rounded, losing the carina. In some specimens the entire surface is adorned with microscopic, frosty, beaded spiral threads alternating with still finer granular lines, in other shells the beaded spirals are inconspicuous over the general surface, but become progressively stronger on approaching the suture. The one bordering the suture are the strongest. The whorls contain ten undulating ribs, slightly tuberculate at the carina, extending from suture to suture. The outer lip is thickened in adult, sinus U-shaped and deep.

Distribution

This extinct marine species was found in

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

strata of the

Dominican Republic The Dominican Republic ( ; es, República Dominicana, ) is a country located on the island of Hispaniola in the Greater Antilles archipelago of the Caribbean region. It occupies the eastern five-eighths of the island, which it shares wit ...

References

External links

Worldwide Mollusc Species Data Base: ''Mangelia maoica''
{{Taxonbar, from=Q39091418 maoica Gastropods described in 1917