''Littorina'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of small sea snails, marine gastropod molluscs in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Littorinidae The Littorinidae are a Taxonomy (biology), taxonomic family (biology), family of over 200 species of sea snails, marine (ocean), marine gastropod molluscs in the clade Littorinimorpha, commonly known as periwinkles and found worldwide. Names In ...

, the winkles or periwinkles.WoRMS (2011). Littorina Férussac, 1822. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=138135 on 2011-04-15 These small

snails A snail is, in loose terms, a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class Gastro ...

live in the

tidal zone The intertidal zone, also known as the foreshore, is the area above water level at low tide and underwater at high tide (in other words, the area within the tidal range). This area can include several types of habitats with various species o ...

of rocky shores.

Overview

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located entirel ...

there are about nine species in this genus, one of which is the rough periwinkle, '' Littorina saxatilis'' (Olivi, 1792). Another closely related (supposed) species ''Littorina tenebrosa'' (Montagu 1802) was thought to be distinct because of its different ecological requirements, but current studies have shown that it is not at all clear whether the two are indeed separate species or whether ''L. tenebrosa'' is perhaps merely an ecotype (an ecological form) of ''L. saxatilis''.Gosling, E.M. (2002). ''The periwinkle as a model in biodiversity studies: a geneticist's view.'' in Marine Biodiversity in Ireland and Adjacent Waters. Ulster Museum. publication no. 8 ''Littorina'' has given its name to the

Littorina Sea Littorina Sea (also Litorina Sea) is a geological brackish water stage of the Baltic Sea, which existed around 7500–4000 BP and followed the Mastogloia Sea, a transitional stage of the Ancylus Lake. This stage and form of the body of wate ...

, the geologic precursor of the

Baltic Sea The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden and the North and Central European Plain. The sea stretches from 53°N to 66°N latitude and ...

Distribution

The periwinkles are found on the seashore in the

littoral zone The littoral zone or nearshore is the part of a sea, lake, or river that is close to the shore. In coastal ecology, the littoral zone includes the intertidal zone extending from the high water mark (which is rarely inundated), to coastal a ...

and sublittoral zone in all parts of the world. In the Baltic they live within the influence of freshwater, and frequently become distorted in consequence.

Description

The thick, pointed shell is turbinated and has few

whorls 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 ...

. 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 ...

is rounded. The outer lip is acute. The

columella Lucius Junius Moderatus Columella (; Arabic: , 4 – ) was a prominent writer on agriculture in the Roman Empire. His ' in twelve volumes has been completely preserved and forms an important source on Roman agriculture, together with the wo ...

is rather flattened and imperforate. The operculum is paucispiral. The lingual teeth are hooked and trilobed. The uncini (small teeth on the radula) are hooked and dentated.

Species

The type species:''Turbo littoreus''

Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...

, 1758 restricts the species in this genus to the northern hemisphere, moderate and cold zones. The tropical species belong in other genera of the same family Bandel, K. & D. Kadolsky (1982). Western Atlantic Species of Nodolittorina (Gastropda: Prosobranchia): comparative morphology and its functional, ecological, phylogenetic and taxonomic implications. Veliger 25 (1): 1-42. Species in the genus ''Littorina'' include * '' Littorina aleutica'' Dall, 1872 * '' Littorina arcana'' Hannaford-Ellis, 1978 * '' Littorina brevicula'' (Philippi, 1844) * '' Littorina compressa'' Jeffreys, 1865 * '' Littorina fabalis'' (Turton, 1825) * '' Littorina horikawai'' Matsubayashi & Habe in Habe, 1979 * '' Littorina islandica'' Reid, 1996 † * '' Littorina kasatka'' Reid, Zaslavskaya & Sergievsky, 1991 * '' Littorina keenae'' Rosewater, 1978 * ''

Littorina littorea The common periwinkle or winkle (''Littorina littorea'') is a species of small edible whelk or sea snail, a marine gastropod mollusc that has gills and an operculum, and is classified within the family Littorinidae, the periwinkles.Reid, David ...

'' (

, 1758),

Common periwinkle The common periwinkle or winkle (''Littorina littorea'') is a species of small edible whelk or sea snail, a marine gastropod mollusc that has gills and an operculum, and is classified within the family Littorinidae, the periwinkles.Reid, Dav ...

* '' Littorina mandshurica'' (Schrenk, 1861) * '' Littorina natica'' Reid, 1996 * '' Littorina obtusata'' (

, 1758), flat periwinkle * '' Littorina petricola'' Arnold, 1908 † * '' Littorina plena'' Gould, 1849 * '' Littorina remondii'' Gabb, 1866 † * '' Littorina saxatilis'' (Olivi, 1792), rough periwinkle * '' Littorina scutulata'' Gould, 1849, checkered periwinkle * '' Littorina sitkana'' Philippi, 1846 * '' Littorina sookensis'' Clark & Arnold, 1923 † *'' Littorina squalida'' Broderip & Sowerby, 1829 * '' Littorina subrotundata'' (Carpenter, 1864) * '' Littorina varia'' * '' Littorina zebra'' ;Species brought into synonymy: * ''Littorina aestuarii'' Jeffreys, 1865: synonym of ''Littorina obtusata'' (Linnaeus, 1758) * ''Littorina affinis'' d'Orbigny, 1839: synonym of ''

Tectarius striatus ''Tectarius striatus'' is a species of sea snail, a marine gastropod mollusk in the family Littorinidae, the winkles or periwinkles. It is endemic to Macaronesia (Azores, Madeira, Savage Islands, Canary Islands and Cape Verde , nationa ...

'' (King & Broderip, 1832) * ''Littorina angulifera'' is a synonym for '' Littoraria angulifera'' (Lamarck, 1822) * ''Littorina arenica'' Jay, 1839: synonym of ''

'' (King & Broderip, 1832) * ''Litorina arenica'' Dunker, 1845: synonym of ''

'' (King & Broderip, 1832) * ''Littorina canariensis'' d'Orbigny, 1839: synonym of ''

'' (King & Broderip, 1832) * ''Littorina cingulifera'' R. W. Dunker, 1845: synonym of '' Littoraria cingulifera'' R. W. Dunker, 1845 * ''Litorina globosa'' Dunker, 1845: synonym of ''

'' (King & Broderip, 1832) *'' Littorina granularis'' Gray, 1839: synonym of ''

Echinolittorina miliaris ''Echinolittorina miliaris'' is a species of sea snail, a marine gastropod mollusk in the family Littorinidae, the winkles or periwinkles. Distribution Description The maximum recorded shell Shell may refer to: Architecture and design * ...

'' (Quoy & Gaimard, 1833) * ''Littorina lamellosa'' Souverbie, 1861: synonym of '' Fossarus lamellosus'' (Souverbie, 1861) * ''Littorina marnat'' Potiez & Michaud, 1838: synonym of '' Echinolittorina punctata'' (Gmelin, 1791) * ''Littorina obesa'' (G.B. Sowerby, 1832): synonym of '' Littoraria coccinea'' (Gmelin, 1791) * ''Littorina petraeus'' (Montagu, 1803): synonym of ''

Melarhaphe neritoides ''Melarhaphe neritoides'', common name : the small periwinkle, is a species of small sea snail, a marine gastropod mollusc in the family Littorinidae, the winkles or periwinkles. This species was previously known as ''Littorina neritoides''. ...

'' (Linnaeus, 1758) * ''Littorina planaxis'' G.B. Sowerby I, 1844: synonym of ''

'' (King & Broderip, 1832) * ''Littorina saxatilis jugosa'' Montagu, 1803: synonym of ''Littorina saxatilis'' (Olivi, 1792) * ''Littorina saxatilis nigrolineata'' Gray, 1839: synonym of ''Littorina saxatilis'' (Olivi, 1792) * ''Littorina striata'' is a synonym for ''

'' (King & Broderip, 1832) * ''Littorina undulata'' Gray, 1839: synonym of ''

Littoraria undulata ''Littoraria undulata'', common name the robust shell, is a species of sea snail, a marine gastropod mollusk in the family Littorinidae, the winkles or periwinkles. Description Up to 2 cm, with dull brown coloration, occasionally darker on ...

'' (Gray, 1839) * ''Littorina unifasciata antipodum'': synonym of ''

Austrolittorina antipodum ''Austrolittorina antipodum'', known as the banded periwinkle, is a species of small sea snail, a marine gastropod in the winkles and periwinkles family, Littorinidae. It is found in New Zealand. It occurs in New Zealand New Zealand ( m ...

'' (Philippi, 1847) * ''Littorina ziczac'' is a synonym for ''

Echinolittorina ziczac ''Echinolittorina ziczac'', previously known as ''Littorina ziczac'', common name the "zebra periwinkle", is a species of small sea snail, a marine gastropod mollusc in the family Littorinidae. This species lives in the tropical Western Atlantic ...

'' (Gmelin, 1791) * ''Littorina zonaria'' Bean, 1844: synonym of ''Littorina saxatilis'' (Olivi, 1792)

References

* Reid D.G. (1996). ''Systematics and evolution of Littorina''. The Ray Society 463p {{taxonbar, from=Q83749 Gastropod genera Littorinidae