Button Snails, also commonly known as Atlantic Pricklywinkle or Toothed Nerite
Phylum: Mollusca, Class: Gastropoda, Order: Littorinimorpha, Family: Littorinidae, Genus: Tectarius, Species: Tectarius muricatus · Littorinidae (Periwinkle family) · Gastropod, whole spiral shells
Species
Tectarius muricatus
Shell Type
Gastropod, whole spiral shells
Family
Littorinidae (Periwinkle family)
Size
Approximately 0.4 to 0.7 inches (10 to 18 mm) in length, which is average for adult specimens of this species.
Color & Pattern
Off-white to light gray base color with distinctive dark brown or reddish-brown speckles, flecks, and irregular banding patterns.
Rarity
Common
Habitat
Supralittoral zone, found on rocks, sea walls, and mangroves well above the high tide mark, breathing air.
Geographic Range
Western Atlantic, from Florida through the Caribbean, the Gulf of Mexico, and down to northern South America.
Description
These small, robust, conical shells feature tightly wound whorls with beaded or nodulose spiral ridges and a rounded aperture, making them look like tiny buttons.
Key Features
Conical shape, nodulose or beaded spiral cords, small rounded aperture with a thickened outer lip, and lack of an umbilicus.
Collector Value
Low to moderate individual value; typically collected in quantity by beachcombers as decorative craft shells rather than high-end collector items.
Condition Notes
Good to fine condition; most specimens are intact with distinct patterning, though some show minor weathering typical of beach or splash-zone collection.
Interesting Facts
These snails are remarkably adapted to terrestrial life, spending almost their entire lives out of water and obtaining oxygen through a modified, vascularized mantle cavity acting as a lung.
Ecological Role
They graze on microalgae, cyanobacteria, and lichens growing on intertidal and supralittoral rocks, serving as important grazers in upper shore marine ecosystems.
Similar Species
Other periwinkles in the Littorina genus, distinguished by Tectarius muricatus's rougher, more distinctly beaded or prickly texture and preference for higher splash-zone habitats.
Beach Finding Tips
Look near the high tide line, particularly on rocky shores, concrete seawalls, piers, and mangrove roots where these snails congregate out of reach of direct waves.