Shark's Eye, also known as Moon Snail
Phylum Mollusca, Class Gastropoda, Order Littorinimorpha, Family Naticidae, Genus Neverita, Species Neverita duplicata · Naticidae (Moon Snail family) · Gastropod, whole spiral shell
Species
Neverita duplicata
Shell Type
Gastropod, whole spiral shell
Family
Naticidae (Moon Snail family)
Size
Approximately 1 to 1.5 inches in diameter, which is a medium-small size for this species. Adults typically range from 1 to 3 inches.
Color & Pattern
Muted brownish-gray base color with a characteristic darker brown or chestnut-colored umbilicus area and apex. The surface is smooth and glossy, showing natural growth lines.
Rarity
Common, frequently found washed ashore on sandy beaches after storms or high tides.
Habitat
Found primarily in shallow marine waters, intertidal zones, and subtidal areas on sandy or muddy bottoms where they burrow beneath the surface.
Geographic Range
Western Atlantic Ocean, extending from Massachusetts along the coast of the United States down to the Gulf of Mexico and Texas.
Description
A sturdy, globular, and smooth marine snail shell with a low spire and a prominent, rounded body whorl. The shell features a distinctive plugged umbilicus (the callus filling the central hole), which is a key identification trait for this species.
Key Features
Globular shape, low spire, smooth polished surface, and a heavy callus that completely or partially fills the umbilicus region.
Collector Value
Low to moderate commercial value; commonly collected by beachcombers rather than purchased, though nice specimens are popular in starter collections.
Condition Notes
Good condition with natural glossy finish intact, minor signs of wear around the edges, no major fractures, collectibility grade is Good.
Interesting Facts
Moon snails are predatory carnivores that drill circular holes into the shells of other bivalves using radular teeth and acidic secretions to consume the prey inside. They are also known for creating sand collars to hold their egg masses.
Ecological Role
Acts as an apex predator among benthic mollusks, helping regulate bivalve populations in sandy substrate ecosystems.
Similar Species
Neverita lewisiana (Northern Moon Snail) and Polinices spp., distinguished by the size and shape of the umbilical callus.
Beach Finding Tips
Look along sandy beaches during low tide, especially after rough surf or storms. Scan the wet sand for rounded shapes or look for the classic sandy 'collars' left behind as egg masses.