Shark Eye Moon Snail (also known as Northern 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 Euspira heros or Lunatia heros)
Shell Type
Gastropod (univalve), whole shell, globose or spherical shape
Family
Naticidae (Moon Snail family)
Size
Approximately 1.5 to 2 inches in diameter, which is typical for a medium-sized specimen. Adults can range from 1 to 3.5 inches.
Color & Pattern
Uniform smooth, chalky to polished pure white, showing heavy sun-bleaching. The original natural brown-to-tan coloration with a darker umbilicus area has been completely bleached or worn away, leaving a pristine monochromatic ivory appearance.
Rarity
Common, frequently found washed up on sandy beaches along the Atlantic and Gulf coasts.
Habitat
Found in shallow marine waters, intertidal to subtidal zones, typically burrowing just beneath the surface of sandy bottoms, sandbars, and mudflats.
Geographic Range
Western Atlantic Ocean, ranging from the Gulf of St. Lawrence down along the coast of the United States to Florida and the Gulf of Mexico.
Description
A classic globular, smooth gastropod shell featuring a low, rounded spire and a large, inflated body whorl. The surface is glossy yet possesses the matte, chalky texture typical of a heavily bleached specimen. The shell lacks any heavy sculpture or ridges, prioritizing a streamlined hydrodynamic shape for burrowing.
Key Features
Globular shape with a very low, compressed spire, a large rounded body whorl, and a smooth porcelain-like surface. Characterized by a plugged or partially covered umbilicus (navel) region typical of the genus Neverita.
Collector Value
Low to moderate commercial value. While extremely popular among casual beachcombers and crafters, pristine naturally colored specimens with intact gloss are preferred by advanced conchologists over sun-bleached finds.
Condition Notes
Good condition whole shell. Completely sun-bleached with loss of original periostracum and brown coloration. Intact structure with minor wear around the aperture lip. Collectibility grade: Good to Fair.
Interesting Facts
Moon snails are famous predatory gastropods. They drill perfectly round, bevel-edged holes into the shells of other bivalves using an acidic secretion and their radula to feed on the soft tissue inside. They are also known for creating 'sand collars'—egg masses cemented together with sand.
Ecological Role
Acts as a primary carnivorous predator and apex scavenger in sandy benthic ecosystems, controlling bivalve populations. Their empty shells provide vital secondary housing for hermit crabs.
Similar Species
Atlantic Moon Snail (Euspira heros) and Mamillated Moon Snail (Neverita delessertiana). Distinguished primarily by the specific structure of the umbilical callus and geographical distribution.
Beach Finding Tips
Look along sandy beaches at low tide, particularly on sandbars or near tidal pools. Walking the wrack line after a storm often reveals freshly washed-up specimens.