''Trochus ochroleucus'',

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contrast ...

the yellow-mouth top shell, is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

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 ...

Trochidae The Trochidae, common name top-snails or top-shells, are a family of various sized sea snails, marine gastropod molluscs in the subclass Vetigastropoda. This family is commonly known as the top-snails because in many species the shell resembles ...

, the top snails.

Description

The size of an adult shell varies between 15 mm and 35 mm. The umbilicate shell has a conoidal shape. The color is isabella-yellow. It is sculptured with very fine subgranose lirae, about 11 on penultimate

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 ...

, 40 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 ...

. The whorls are rather convex, the body whorl scarcely angled. The margin of the umbilicus is dentate. The columella is very oblique, not solute above and terminates below in a simple denticle. The lip is thickened and corrugated within. The form is just like ''

Clanculus cruciatus ''Clanculus cruciatus'' is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails. Description The size of the shell varies between 6 mm and 10 mm. The narrowly umbilicate shell has a globose-coni ...

'' (Linnaeus, 1758). The shell consists of 6 to 7 rather rounded whorls, the body whorl not angulated to speak of, and with a rather convex base. The spiral cinguli gradually increase in number, so that on the penultimate whorl there are about 11, on the body whorl about 40 of them. On the upper whorls they are distinctly granulose, on the last almost entirely smooth. The umbilicus is pretty narrow, its margin dentate. The columella is very oblique, not free above, with a small but prominent denticle below. The outer lip is thickened within, with five folds, but near the edge with numerous wrinkles.H. Pilsbry, Manual of Conchology XI, Academy of Natural Sciences, Philadelphia
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Distribution

This species occurs in the

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by th ...

, and in the Pacific Ocean off the

Philippines The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

References

* Philippi, Conchyl. Cab. p. 243, t. 36, f. 16. (1853) * Drivas, J.; Jay, M. (1987). ''Coquillages de La Réunion et de l'Île Maurice''. Collection Les Beautés de la Nature. Delachaux et Niestlé: Neuchâtel. . 159 pp.

External links

* {{DEFAULTSORT:Trochus ochroleucus ochroleucus Gastropods described in 1791