Shark Eye Moon Snail (also known as Northern Moon Snail or Atlantic Moon Snail)
Phylum: Mollusca, Class: Gastropoda, Order: Littorinimorpha, Family: Naticidae, Genus: Neverita, Species: Neverita duplicata · Naticidae (Moon Snail family) · Gastropod (univalve), whole shell, globose or spherical shape
Species
Neverita duplicata (formerly Polinices duplicatus)
Shell Type
Gastropod (univalve), whole shell, globose or spherical shape
Family
Naticidae (Moon Snail family)
Size
Approximately 1 inch (25 mm) in the provided image. This is a juvenile or smaller specimen, as typical adult Shark Eye snails range from 2 to 3.5 inches (50-90 mm) in diameter.
Color & Pattern
The base color is a creamy white to pale tan, featuring a distinctive large, warm chestnut-brown or caramel-colored patch radiating from the apex/umbilicus area. The surface is smooth with a glossy porcelain-like finish, though showing signs of gentle weathering.
Rarity
Common, frequently found by beachcombers along sandy Atlantic and Gulf coasts.
Habitat
Found in shallow marine waters, primarily inhabiting intertidal and subtidal sandy flats, sandbars, and shallow coastal bays down to moderate depths. They are benthic animals that spend most of their time buried beneath the sand surface.
Geographic Range
Western Atlantic Ocean, ranging from Massachusetts south along the coast of the United States, through the Gulf of Mexico, and down to the Caribbean and South America.
Description
This is a classic moon snail shell, characterized by its smooth, globular form with a low spire and a large body whorl. The surface is polished and glossy, reflecting natural marine tumbling. While the underside and umbilicus are obscured in this view, the dorsal side exhibits the hallmark rich brownish central patch contrasting against the pale background.
Key Features
Globular shape with a very low, rounded spire, smooth polished surface, and the characteristic brown-to-tan central marking surrounding the apical area, separating it from other pale moon snail species.
Collector Value
Low to moderate commercial value. While extremely popular among amateur beachcombers and shell crafters, they are too common for high-end collector valuation. Specimens typically trade for nominal amounts or are gathered freely on beaches.
Condition Notes
Good condition with a smooth, glossy surface and intact structure. No major fractures or chips are visible, though minor surface weathering is present consistent with a beach-cast specimen. Collectibility grade is Good.
Interesting Facts
Moon snails are formidable marine predators. They hunt bivalves by boring a perfectly neat, countersunk hole through the victim's shell using a specialized radula and acidic secretions, then feeding on the soft tissue inside. Their egg masses, known as 'sand collars,' are formed of sand glued together with mucus.
Ecological Role
As apex carnivorous gastropods in sandy bottom ecosystems, moon snails help control bivalve populations. They serve as food for various marine predators including larger fish, sea turtles, and gulls. Their discarded shells frequently provide essential mobile homes for hermit crabs.
Similar Species
Neverita lewisii (Lewis's Moon Snail, which is larger and generally lacks the strong dark central patch) and Euspira heros (Northern Moon Snail, which has a higher spire and lighter overall coloration).
Beach Finding Tips
Look along high-energy sandy beaches during low tide, particularly near sandbars or tidal pools. Searching the swash zone or digging gently in wet sand where bubbles or small mounds indicate buried mollusks can also reveal live or pristine specimens.