Prickly Winkle, also known as the Beaded Periwinkle
Phylum Mollusca, Class Gastropoda, Order Littorinimorpha, Family Littorinidae, Genus Cenchritis, Species Cenchritis muricatus · Littorinidae (Periwinkle family) · Gastropod (snail/univalve), whole shell, spiral shape
Species
Cenchritis muricatus
Shell Type
Gastropod (snail/univalve), whole shell, spiral shape
Family
Littorinidae (Periwinkle family)
Size
Approximately 0.75 inches (1.5-2 cm) in length, which is average to large for this species. Adults typically range from 0.5 to 1 inch.
Color & Pattern
Uniform off-white to creamy chalky white color, likely sun-bleached. The exterior features rows of beaded nodules.
Rarity
Common to Very Common depending on the specific rocky shoreline or beach location.
Habitat
High intertidal and supratidal zones, commonly found on rocky shores, splash zones, sea walls, and mangrove roots above the high-tide mark. Marine and air-breathing.
Geographic Range
Western Atlantic, including Florida, the Caribbean, the Gulf of Mexico, Bermuda, and down to northern South America.
Description
A small, solid, conical shell featuring heavily sculptured whorls adorned with distinct rows of small, beaded nodules or tubercles. The aperture is rounded and simple, with a pointed spire.
Key Features
Conical shape, distinctly beaded or nodular spiral cords on all whorls, and an affinity for high-intertidal and supratidal rocky environments.
Collector Value
Low to moderate commercial value, widely found by beachcombers and commonly collected as a representative littoral species. Usually worth a few cents to a dollar.
Condition Notes
Good condition whole shell, uniformly bleached white due to sun exposure, with intact whorls and structure. Collector grade is Good.
Interesting Facts
Cenchritis muricatus is famously terrestrial in its habits, often living high above the waterline on rocks and cliffs where it breathes air using a modified mantle cavity.
Ecological Role
Grazes on microalgae, biofilms, and lichens on rocks in the supratidal zone. Serves as a food source for coastal birds and small crabs.
Similar Species
Littorina species (periwinkles), which generally lack the pronounced prickly or beaded nodular sculpture of the Prickly Winkle.
Beach Finding Tips
Look high up on rocky coastlines, jetty rocks, limestone outcroppings, or seawalls well above the normal high tide line, especially in the Caribbean and Florida.