''Trochus flammulatus'' 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 height of the shell attains 40 mm, its diameter 38 mm. The general form of this species is similar to ''

Trochus maculatus ''Trochus maculatus'', common name the maculated top shell, 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 25 mm and 65 mm. This is an e ...

''. It is thick, solid, and heavy. The upper surface is longitudinally flammulated with dark red, the stripes distinct and broad, about as wide as the intervening whitish spaces. The stripes of 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 ...

are continued over the obtuse periphery upon the base, where they become narrower, often bifurcate, and are zigzag. The

sculpture Sculpture is the branch of the visual arts that operates in three dimensions. Sculpture is the three-dimensional art work which is physically presented in the dimensions of height, width and depth. It is one of the plastic arts. Durable sc ...

above is like that of ''Trochus maculatus'', the rows of granules about five or six on each whorl and the lower ones compressed and narrow. There is, besides, a fine, superficial, secondary sculpture of slightly oblique longitudinal minute wrinkles, which are continued over the periphery upon the base, forming there a finely shagreened pattern by the intersection of fine incremental stride. The base of the shell is rather more convex than in the typical ''Trochus maculatus'', and its outer portion is nearly free from spiral line. These number about six. They are finely, closely crenulated by the wrinkles of the surface. The outer lip of 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 not crenulated, the other characters of the aperture and columella are precisely as in ''

Trochus incrassatus ''Trochus stellatus'', common name the stellate trochus, is a species of sea snail, a marine gastropod mollusk in the family (biology), family Trochidae, the top snails.

''.H. Pilsbry, Manual of Conchology XI, Academy of Natural Sciences, Philadelphia
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Distribution

This species occurs in the Indian Ocean off the Mascarenes,

Aldabra Aldabra is the world's second-largest coral atoll, lying south-east of the continent of Africa. It is part of the Aldabra Group of islands in the Indian Ocean that are part of the Outer Islands of the Seychelles, with a distance of 1,120 k ...

and Chagos.

References

* 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 Flammulatus flammulatus Gastropods described in 1822