Shark's Eye, Moon Snail
Phylum: Mollusca, Class: Gastropoda, Order: Littorinimorpha, Family: Naticidae, Genus: Neverita, Species: Neverita duplicata · Naticidae (Moon Snail family) · Gastropod (univalve); whole shell (top view), globose/spiral shape
Species
Neverita duplicata
Shell Type
Gastropod (univalve); whole shell (top view), globose/spiral shape
Family
Naticidae (Moon Snail family)
Size
Approximately 1-1.5 inches in diameter based on surface grain; average for this species (adults reach 3 inches)
Color & Pattern
Glossy creamy-white to slate grey base; distinctive dark brown/purple 'eye' at the apex (protoconch). Natural color present but slightly matte, suggesting beach-worn weathering.
Rarity
Very Common; a staple find for beachcombers along the East Coast of the United States.
Habitat
Found in intertidal and shallow subtidal zones, typically semi-buried in sandy substrates or mudflats.
Geographic Range
Western Atlantic, ranging from Massachusetts south to Florida and the Gulf of Mexico.
Description
A smooth, globose snail shell characterized by a low spire and a very large body whorl. The surface is porcelaneous and lacks heavy sculpture. Seen from above, the dark apical whorls resemble a shark's eye.
Key Features
Low spire; large umbilicus (usually covered by a thick callus in this species); dark purple-brown central 'eye' spot; smooth, rounded profile.
Collector Value
Low monetary value ($1-$5) due to abundance, but highly desired by beginner collectors for its aesthetic 'eye' pattern.
Condition Notes
Good condition. The apex is intact, the color is visible but the natural high-gloss 'wet' look is somewhat dulled by sand abrasion. No visible predator bore-holes.
Interesting Facts
The living animal is much larger than its shell and can almost entirely envelop it. They are predatory 'drills' that use a radula to bore perfectly circular holes into bivalve shells to eat the inhabitants.
Ecological Role
A key predator of clams and other mollusks; keeps bivalve populations in check. The empty shells are frequently used as homes by large hermit crabs.
Similar Species
Neverita delessertiana (found in the Gulf, has a more divided callus) and Euspira heros (Northern Moon Snail, which lacks the dark 'eye' and has a deep, open umbilicus).
Beach Finding Tips
Look near the low-tide line on sandy beaches or in tidal pools. They are often found by spotting a slight hump in the wet sand where the snail is buried.