''Trochus erithreus'' 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 ...

, 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 ...

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.Bouchet, P.; Rosenberg, G.; Gofas, S. (2014). Trochus erithreus Brocchi, 1821. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=225666 on 2014-06-14

Description

The height of the shell varies between 33 mm and 35 mm, its diameter between 37 mm and 40 mm. The rather thin and inflated shell has a conical shape and is false-umbilicate. The

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 ...

is acute. The about 7

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 are somewhat concave and generally traversed by several conspicuously granose lirae in the middle. They are a little gibbous above and below, obliquely undulate below the sutures, and frequently on the periphery also. The whole surface is more or less finely spirally lirate with subgranulose lirae. The convex base of the shell is concentrically lirate with about 7 granose narrow lirae. Their interstices are generally occupied by concentric striae. The color of the shell is cinereous grayish or pinkish, striped and maculated above with reddish; unicolored pinkish or radiately marked below. The large

aperture In optics, the aperture of an optical system (including a system consisting of a single lens) is the hole or opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image o ...

is smooth and pearly within. The basal

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 simple. The oblique

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 very deeply inserted, its entire edge nearly straight, not dentate. The deep umbilical tract is narrow, pearly. bearing a single strong spiral white rib near its base, which does not attain the edge of the

It feeds on algae and is often seen by divers.

Distribution

This species occurs in the Indian Ocean (

Aldabra Aldabra, the world's second-largest coral atoll (the largest is Kiritimati), is located 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 (Seychelles), Outer Islands ...

Region), the

Red Sea The Red Sea is a sea inlet of the Indian Ocean, lying between Africa and Asia. Its connection to the ocean is in the south, through the Bab-el-Mandeb Strait and the Gulf of Aden. To its north lie the Sinai Peninsula, the Gulf of Aqaba, and th ...

, the Persian Gulf (off

Kuwait Kuwait, officially the State of Kuwait, is a country in West Asia and the geopolitical region known as the Middle East. It is situated in the northern edge of the Arabian Peninsula at the head of the Persian Gulf, bordering Iraq to Iraq–Kuwait ...

), the

Mediterranean Sea The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern Eur ...

(as a

Lessepsian migrant The Lessepsian migration (or Erythrean invasion) is the migration of marine species along the Suez Canal, usually from the Red Sea to the Mediterranean Sea, and more rarely in the opposite direction. When the canal was completed in 1869, fish, ...

) and in the Northern Atlantic Ocean.

References

* Brocchi (1821). ''Continuazione e fine del catalogo delle conchiglie raccolte dal Sig. G. Forni nel seno Arabico ed illustrate dal Sig. Brocchi''. Biblioteca Italiana : 24: 209–226. page(s): * Spry, J.F. (1961). ''The sea shells of Dar es Salaam: Gastropods''. Tanganyika Notes and Records 56 * Taylor, J.D. (1973). ''Provisional list of the mollusca of Aldabra Atoll''. * Bosch D.T., Dance S.P., Moolenbeek R.G. & Oliver P.G. (1995) ''Seashells of eastern Arabia''. Dubai: Motivate Publishing. 296 pp * Gofas, S.; Le Renard, J.; Bouchet, P. (2001). Mollusca, in: Costello, M.J. et al. (Ed.) (2001). ''European register of marine species: a check-list of the marine species in Europe and a bibliography of guides to their identification.'' Collection Patrimoines Naturels, 50: pp. 180–213 * Streftaris, N.; Zenetos, A.; Papathanassiou, E. (2005). ''Globalisation in marine ecosystems: the story of non-indigenous marine species across European seas.'' Oceanogr. Mar. Biol. Annu. Rev. 43: 419–453

External links

* {{Taxonbar, from=Q6031646 erithreus Gastropods described in 1821