Shark's Eye Moon Snail (also known as the Atlantic Moon Snail or Northern Moon Snail)
Phylum: Mollusca, Class: Gastropoda, Order: Littorinimorpha, Family: Naticidae, Genus: Neverita, Species: Neverita duplicata · Naticidae (Moon Snail family) · Gastropod (univalve) with a smooth, globular, spiral shape
Species
Neverita duplicata
Shell Type
Gastropod (univalve) with a smooth, globular, spiral shape
Family
Naticidae (Moon Snail family)
Size
Approximately 1.5 to 2 inches in diameter, which is medium-sized for this species. Adults typically range from 1 to 3 inches.
Color & Pattern
The exterior features a glossy, smooth finish with a warm brownish-tan or greyish base color, accented by a distinct dark brown or chestnut-colored band swirling around the shoulder and spire. The callus near the aperture is dark brown. The colors are natural and well-preserved.
Rarity
Common, frequently found washed ashore on sandy beaches after storms or at low tide.
Habitat
Found primarily in shallow subtidal and intertidal zones, buried just beneath the surface of sandy bottoms, mudflats, and sandbars in marine environments.
Geographic Range
Western Atlantic from Massachusetts down to the Gulf of Mexico, the Caribbean, and parts of South America.
Description
A classic, sturdy, globular gastropod shell with a low spire and a large body whorl. The surface is exceptionally smooth and polished to the touch, lacking heavy ribs or spines. The distinctive calloused area covers the umbilicus, giving it a solid and compact appearance.
Key Features
Smooth, globular shape, low spire, large body whorl, and a characteristic dark brown callus covering the umbilicus region.
Collector Value
Low to moderate commercial value. While very popular among casual beachcombers and beginner shell collectors due to their pleasing shape, they are too common for high-end specialist collections unless exceptionally large or unusually patterned.
Condition Notes
Good to Fine condition. The shell is intact with nice natural luster and clear color banding, though showing minor surface wear and minor pitting near the apex consistent with wave action and beach tumbling.
Interesting Facts
Moon snails are carnivorous predators that drill perfectly circular, bevel-edged holes into the shells of other mollusks using a combination of acidic secretions and their radula to feed on the soft tissue inside.
Ecological Role
They act as apex predators among benthic marine mollusks, regulating bivalve populations and maintaining the health of coastal sandflat ecosystems. Empty shells also provide vital housing for hermit crabs.
Similar Species
Neverita lewisii (Lewis's Moon Snail) which is generally larger and lighter in color on the West Coast, and Euspira heros (Northern Moon Snail) which is taller-spired and lighter without the dark umbilicus callus.
Beach Finding Tips
Look along high-tide lines on sandy beaches, especially after storms or during extreme low tides. Keep an eye out for their famous 'sand collars' (egg masses made of sand and mucus), which indicate moon snails are active in the area.