Shark Eye or Atlantic Moon Snail (fragment/eroded)
Phylum: Mollusca, Class: Gastropoda, Order: Littorinimorpha, Family: Naticidae, Genus: Neverita, Species: Neverita duplicata · Naticidae (Moon Snail family) · Gastropod (univalve). This specimen is a heavily eroded fragment/internal cast (steinkern-like) or a sun-bleached shell remnant, showing a globose or spiral-disc shape.
Species
Neverita duplicata (likely, based on the remnant shape and color)
Shell Type
Gastropod (univalve). This specimen is a heavily eroded fragment/internal cast (steinkern-like) or a sun-bleached shell remnant, showing a globose or spiral-disc shape.
Family
Naticidae (Moon Snail family)
Size
Approximately 1.5 to 2.25 inches in diameter. This falls within the typical adult range of 1-3.5 inches for the species.
Color & Pattern
Uniformly matte gray to light slate, likely due to extreme sun-bleaching or mineralization. The natural glossy finish and distinctive blue-eye pattern are gone. The interior shows a darker, more glassy gray where the shell has fractured.
Rarity
Very Common. As a whole shell, these are ubiquitous beach finds; as a fragment in this condition, they are very frequently found in the 'drift' line.
Habitat
Coastal marine environments, typically shallow subtidal or intertidal zones with sandy substrates where they can burrow for prey.
Geographic Range
Western Atlantic, typically from Massachusetts south to Florida and the Gulf of Mexico.
Description
This is a heavily weathered and fractured specimen of a moon snail. The typical globose, smooth-walled architecture of the Naticidae family is visible despite the damage. The shell lacks its original periostracum and lustre, showing a dull, stone-like texture. A large lateral fracture reveals the thickness of the calcium carbonate wall and a glimpse of the internal spiraling whorls.
Key Features
Globose, rounded shape; presence of a wide, slightly flattened spire (though heavily eroded here); and the thick, sturdy wall structure characteristic of predatory moon snails.
Collector Value
Minimal. While the species is classic, the condition of this specific specimen makes it a 'beach find' rather than a 'collection piece.' Typical value is under $1 USD.
Condition Notes
Poor/Beach-worn. The shell is fractured and lacks the vital taxonomic markers (like the umbilical callus) needed for a 100% positive ID. It has significant environmental erosion and bleaching. Collectibility grade: Poor.
Interesting Facts
Moon snails are voracious predators that use a specialized tongue (radula) to drill perfectly circular holes into bivalves to consume them. Their eggs are laid in distinctive 'sand collars' that look like discarded plastic or rubber rings on the beach.
Ecological Role
High-level predator in the sandy benthic community, controlling populations of clams and other bivalves. Currently, they have no special conservation status as they are abundant.
Similar Species
Euspira heros (Northern Moon Snail) which lacks the flattened callus area, or Polinices lacteus (Milk Moon Snail) which is typically whiter but smaller.
Beach Finding Tips
Look near the low tide mark on sandy beaches after a storm. Search for 'sand collars'—if you see them, moon snails are nearby in the sand just offshore.