Moon Snail or Shark's Eye (also known as Neverita or Natica)
Phylum: Mollusca, Class: Gastropoda, Order: Littorinimorpha, Family: Naticidae, Genus: Neverita, Species: Neverita duplicata · Naticidae (Moon Snail family) · Gastropod (univalve) with a globular, spiral shape
Species
Neverita duplicata (formerly Polinices duplicatus)
Shell Type
Gastropod (univalve) with a globular, spiral shape
Family
Naticidae (Moon Snail family)
Size
Approximately 2 to 3 inches in diameter, which is typical for an adult of this species. Adults generally range from 1.5 to 3.5 inches.
Color & Pattern
Uniform glossy stark white, likely polished, acid-washed, or heavily bleached to remove its natural brownish-gray coloration and darker umbilicus region.
Rarity
Very Common; frequently washes up on sandy beaches throughout its natural geographic range.
Habitat
Found in marine environments, specifically shallow subtidal and intertidal zones, buried just beneath the surface of sandy bottoms and mudflats.
Geographic Range
Western Atlantic Ocean, ranging from coastal Massachusetts down through the Gulf of Mexico, Caribbean, and South America.
Description
A smooth, highly polished, globular univalve shell with a low spires and a rounded body whorl. The surface shows faint growth lines under a pristine white finish.
Key Features
Globular, spherical shape with a low spire, very smooth body whorl, and a characteristic thick callus filling the umbilicus area (though obscured or modified in polished decorative specimens).
Collector Value
Low to moderate value for collectors. While extremely common, polished specimens like this are frequently sold in souvenir and shell shops as decorative items rather than prized scientific specimens.
Condition Notes
Good decorative condition. The shell is fully intact, but appears to have been commercially processed, polished, or acid-treated to achieve a uniform bright white appearance, removing any natural periostracum or patterning.
Interesting Facts
Moon snails are predatory carnivores that drill neat, countersunk holes into the shells of other bivalves using an acidic secretion and a rasping radula to consume the prey inside.
Ecological Role
Acts as an important apex predator in soft-bottom marine benthic communities by controlling bivalve populations. Their egg masses, known as 'sand collars', are iconic composite structures of sand and mucus.
Similar Species
Natica vouloutas and other Polinices species, distinguished mainly by the specific shape and size of the umbilical callus and subtle variations in shape.
Beach Finding Tips
Look along sandy shorelines at low tide, especially after storms. You can often spot them by searching for circular depressions or hummocks in the sand where they have moved just beneath the surface.