The Littorinidae are a taxonomic family of over 200 species of sea snails, marine gastropod molluscs in the clade Littorinimorpha, commonly known as periwinkles and found worldwide.
[3] In English-speaking countries, gastropod molluscs from other families, such as the Neritidae, are sometimes also commonly known as "winkles" because they are small, round snails that occupy a similar ecological niche.
These subfamilies have been recognized in the taxonomy of Bouchet & Rocroi (2005): Genera within the family Littorinidae include:[4] subfamily ?
David G. Reid; Suzanne T. Williams (2004).
"The subfamily Littorininae in the Temperate Southern Hemisphere: the genera Nodilittorina, Austrolittorina and Afrolittorina" (PDF).