''Mitromorpha alphonsiana'' is a species of

sea snail Sea snails are slow-moving marine (ocean), marine gastropod Mollusca, molluscs, usually with visible external shells, such as whelk or abalone. They share the Taxonomic classification, taxonomic class Gastropoda with slugs, which are distinguishe ...

, a marine

gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...

mollusk Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Mitromorphidae Mitromorphidae is a monophyletic family of small to medium-sized sea snails, marine gastropod mollusks in the superfamily Conoidea Conoidea is a Taxonomic rank, superfamily of predatory sea snails, marine (ocean), marine gastropod Mollusc, mo ...

Description

The length of the shell attains 6 mm, its diameter 2.75 mm. The small shell has a biconic shape and an acuminate

apex The apex is the highest point of something. The word may also refer to: Arts and media Fictional entities * Apex (comics) A-Bomb Abomination Absorbing Man Abraxas Abyss Abyss is the name of two characters appearing in Ameri ...

. The shell has a white color. The middle of the

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). In nature File:Photograph and axial plane floral diagra ...

s is ornated with white and yellow dots, alternating on the ribs, below two series of granules, cut by subsutural striae. Those two rows of dots on the superior part have a violet-rose color only on the first two whorls. This color nuance changes on the

body whorl The body whorl is part of the morphology (biology), morphology of the gastropod shell, 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 ...

. Here the two upper rows of dots are white. The shell contains 7–8 whorls, of which 2–3 smooth and milky white whorls in 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 " ...

. The others are convex with an indistinct suture. The longitudinal ribs are dense and are crossed by two transverse striae on each whorl, subsutarally sulcate and decussate by small lirae. The superior part of the narrow, oblique body whorl is slightly rounded, the inferior part attenuate and elongate. The superior part of the

columella Lucius Junius Moderatus Columella (, Arabic: ) was a prominent Roman writer on agriculture in the Roman Empire. His in twelve volumes has been completely preserved and forms an important source on Roman agriculture and ancient Roman cuisin ...

is concave, inflated at the middle. The convex outer

lip The lips are a horizontal pair of soft appendages attached to the jaws and are the most visible part of the mouth of many animals, including humans. Mammal lips are soft, movable and serve to facilitate the ingestion of food (e.g. sucklin ...

is incrassate and sinuate at the suture and has a sharp margin.Hervier, J. "Le genre Columbella dans l’Archipel de la Nouvelle-Calédonie." Journal de Conchyliologie 46 (1899): 305–391
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Distribution

This marine species occurs off

New Caledonia New Caledonia ( ; ) is a group of islands in the southwest Pacific Ocean, southwest of Vanuatu and east of Australia. Located from Metropolitan France, it forms a Overseas France#Sui generis collectivity, ''sui generis'' collectivity of t ...

and the

Tuamotu Islands The Tuamotu Archipelago or the Tuamotu Islands (, officially ) are a French Polynesian chain of just under 80 islands and atolls in the southern Pacific Ocean. They constitute the largest chain of atolls in the world, extending (from northwest to ...

References

External links

MNHN, Paris: ''Mitromorpha alphonsiana''
* *
Salvat, Bernard, and Jean Tröndlé. "Biogéographie des mollusques marins de Polynésie française." Revue d’Ecologie (Terre et Vie) 72.3 (2017): 215–257
{{DEFAULTSORT:Mitromorpha Alphonsiana alphonsiana Gastropods described in 1899