''Crosseola bellula'' is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of small

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 ...

micromollusc A micromollusc is a shelled mollusc which is extremely small, even at full adult size. The word is usually, but not exclusively, applied to marine molluscs, although in addition, numerous species of land snails and freshwater molluscs also ...

, 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 ...

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

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 ...

Conradiidae.MolluscaBase (2019). MolluscaBase. Crosseola bellula (A. Adams, 1865). Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=997989 on 2020-01-27

Description

The height of the shell attains 2 mm. The white shell has a depressed turbinate shape. 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 contain spiral lirae and lack

varices A varix (: varices) is an abnormally dilated blood vessel with a tortuous course. Varices usually occur in the venous system, but may also occur in arterial or lymphatic vessels. Examples of varices include: * Varicose veins, large tortuous veins ...

. The interstices are neatly cancellated. The simple 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 thin and has an acute margin.

Distribution

This marine species occurs off the

Philippines The Philippines, officially the Republic of the Philippines, is an Archipelagic state, archipelagic country in Southeast Asia. Located in the western Pacific Ocean, it consists of List of islands of the Philippines, 7,641 islands, with a tot ...

and

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

References

Sources

* Higo, S., Callomon, P. & Goto, Y. (1999) ''Catalogue and Bibliography of the Marine Shell-Bearing Mollusca of Japan''. Elle Scientific Publications, Yao, Japan, 749 pp * Rubio F. & Rolán E. (2017). New species of Crosseolidae Hickman, 2013 (Gastropoda) from the Tropical Indo-Pacific. Novapex. 18(1-2): 17-34 * Rubio F. & Rolán E. (2019). New species of Conradiidae Golikov & Starobogatov, 1987 (= Crosseolidae Hickman, 2013) (Gastropoda: Trochoidea) from the Tropical Indo-Pacific II. The genus Crosseola and the description of Crossolida n. gen. Novapex. 20(3): 49–91.

External links

World Register of Marine Species

Adams A. (1865). On some new genera of Mollusca from the seas of Japan. Annals and Magazine of Natural History. ser. 3, 15: 322-324
{{Taxonbar, from=Q5188538 bellula Gastropods described in 1865