Littorina

Littorina is a genus of small, air-breathing sea snails, commonly known as periwinkles or winkles, that belong to the family Littorinidae. These snails are found in intertidal zones and saltmarshes worldwide, playing an important role in coastal ecosystems. They are generally characterized by their conical shells and relatively small sizes, with most species reaching a maximum length of 2-3 centimeters. Their ability to survive both in water and out of water makes them a fascinating example of adaptation in marine environments.

Littorina subrotundata

Common Names

The most common names for Littorina snails are periwinkles and winkles. However, depending on the specific species and location, other names may be used, such as "black periwinkle," "common periwinkle," or "dog whelk."

Characteristics

Littorina species share several common characteristics:

  • Conical shells: The shells of Littorina are typically conical in shape, with a pointed apex and a wider base. The shell surface can be smooth, ribbed, or spiraled, depending on the species.
  • Small size: Most Littorina species reach a maximum length of 2-3 centimeters.
  • Air-breathing: Littorina snails are adapted to life in the intertidal zone and can breathe air through their gills.
  • Operculum: Littorina have a hard, protective plate called an operculum that closes the opening of their shell when they withdraw inside. This provides protection from predators and dehydration.
  • Herbivorous diet: Most Littorina species are herbivores, feeding on algae, detritus, and other organic matter.

Environments

Littorina snails are found in a wide variety of intertidal and saltmarsh environments worldwide. Their specific habitat preferences vary by species, but they typically inhabit:

  • Rocky shores: Many Littorina species are found on rocky shores, clinging to rocks and other hard substrates.
  • Mudflats: Some species, such as Littorina littorea, are found in mudflats, where they burrow into the sediment.
  • Saltmarshes: Littorina snails can also be found in saltmarshes, where they graze on the vegetation.

References

For more detailed information about Littorina, you can refer to these sources: