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Common periwinkle

Common periwinkle
Sea snail, underneath, full view.jpg
Periwinkle emerging from its shell, Sweden
Littorina littorea 001.jpg
L. littorea on the edge of a small sandy beach in Woods Hole, Massachusetts
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
(unranked): clade Caenogastropoda
clade Hypsogastropoda
clade Littorinimorpha
Superfamily: Littorinoidea
Family: Littorinidae
Genus: Littorina
Species: Littorina littorea
Binomial name
Littorina littorea
(Linnaeus, 1758)
Synonyms
  • Littorina armoricana Locard, 1886
  • Littorina bartonensis Brown, 1843
  • Littorina communis Brown, 1843
  • Littorina litorea (Turton, 1819)
  • Littorina litorea var. brevicula Jeffreys, 1865
  • Littorina litorea var. paupercula Jeffreys, 1865
  • Littorina litorea var. sinistrorsa Jeffreys, 1865
  • Littorina litorea var. turrita Jeffreys, 1865
  • Littorina littorea f. intermedia Brøgger, 1901
  • Littorina littorea var. angulata Harmer, 1920
  • Littorina littorea var. antiqua Wood, 1848
  • Littorina littorea var. balteata Dautzenberg & Durouchoux, 1912
  • Littorina littorea var. complanata Harmer, 1920
  • Littorina littorea var. conica Harmer, 1920
  • Littorina littorea var. deformis Wood, 1848
  • Littorina littorea var. delphinula Wood, 1848
  • Littorina littorea var. distorta Harmer, 1920
  • Littorina littorea var. elegans Wood, 1848
  • Littorina littorea var. fuscofasciatus Middendorff, 1849
  • Littorina littorea var. major Dautzenberg & Durouchoux, 1913
  • Littorina littorea var. miniata Dautzenberg & Durouchoux, 1900
  • Littorina littorea var. pallida Dautzenberg & Durouchoux, 1900
  • Littorina littorea var. pallidefasciatus Middendorff, 1849
  • Littorina littorea var. parva Harmer, 1920
  • Littorina littorea var. picta Wood, 1848
  • Littorina littorea var. pyramidata Wood, 1848
  • Littorina littorea var. sanguinea Dautzenberg & Durouchoux, 1906
  • Littorina littorea var. truncata Harmer, 1920
  • Littorina littorea var. unicarinata Raeymaekers, 1889
  • Littorina parva Teilman-Friis, 1898
  • Littorina rudis var. aurantia Dautzenberg & P. Fischer, 1925
  • Littorina rudis var. reevei Harmer, 1921
  • Littorina sphaeroidalis Locard, 1886
  • Littorina vulgaris J. Sowerby, 1832
  • Turbo bicarinatus Woodward, 1833
  • Turbo carinatus Woodward, 1833
  • Turbo elongatus Woodward, 1833
  • Turbo litoreus Turton, 1819
  • Turbo littoreus Linnaeus, 1758 (basionym)
  • Turbo sulcatus Woodward, 1833
  • Turbo ustulatus Lamarck, 1822
  • Turbo ventricosus Woodward, 1833
External video
Dredging for periwinkles, YouTube video
Snorkeling for periwinkles, YouTube video

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

This is a robust intertidal species with a dark and sometimes banded shell. It is native to the rocky shores of the northeastern, and introduced to the northwestern, Atlantic Ocean.

There is another snail known as small periwinkle or Melarhaphe neritoides that looks similar, but is smaller in size.

The shell is broadly ovate, thick, and sharply pointed except when eroded. The shell contains six to seven whorls with some fine threads and wrinkles. The color is variable from grayish to gray-brown, often with dark spiral bands. The base of the columella is white. The shell lacks an umbilicus. The white outer lip is sometimes checkered with brown patches. The inside of the shell has a chocolate-brown color.

The width of the shell ranges from 10 to 12 mm at maturity, with an average length of 16–38 mm.

Shell height can reach up to 30 mm, 43 mm or 52 mm.

As a result of its robust nature, Littorina littorea can be highly variable in phenotype with several different morphs present. Its phenotypic variations may be indicative of a speciation event, as opposed to phenotypic plasticity. This is of particular importance to evolutionary biology, as it presents the possible opportunity to view a transitional phase in the evolutionary life of an organism.

Measuring the shell from the end of the aperture to the apex reveals the length of the snail. Turning the shell over with the aperture flat on a surface and measuring vertically reveals the height of the snail. These measurements can be done using a caliper.

Common periwinkles are native to the northeastern coasts of the Atlantic Ocean, including northern Spain, France, England, Scotland, Ireland, Scandinavia, and Russia.


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