Littorina

The genus Littorina, commonly known as periwinkles, comprises small marine snails belonging to the family Littorinidae. These snails are widely distributed along shorelines, typically found on rocks, stones, or pilings between high and low tide marks. Some species inhabit mud flats or mangrove roots in tropical regions.1

The common periwinkle, Littorina littorea, is a notable species, reaching up to 4 cm in length with a solid, spiral shell. It is abundant on the rocky shores of northern Europe and was introduced to North America in the mid-19th century. Periwinkles are primarily herbivorous and play a significant role in their ecosystems as a food source for shorebirds. Their reproductive habits vary, with some species brooding their young internally while others release eggs into the water.1