Chestnut Cowrie
Phylum: Mollusca, Class: Gastropoda, Order: Littorinimorpha, Family: Cypraeidae, Genus: Neobernaya, Species: N. spadicea · Cypraeidae (Cowrie family) · Gastropod (snail); Whole shell; Egg-shaped/Oval with an involute spire and a long, narrow aperture.
Species
Neobernaya spadicea (Formerly Cypraea spadicea)
Shell Type
Gastropod (snail); Whole shell; Egg-shaped/Oval with an involute spire and a long, narrow aperture.
Family
Cypraeidae (Cowrie family)
Size
Approximately 1-1.5 inches. This specimen appears to be on the smaller side of the adult range, which typically spans 1 to 3 inches.
Color & Pattern
Glossy white base and margins with a central, rich chestnut-brown patch on the dorsum. This specimen shows a characteristically mottled or broken pattern toward the edges of the brown patch. The underside (base) is typically milky white to cream.
Rarity
Common to Uncommon. While geographically localized, they are frequently found by divers and occasionally washed up on beaches after storms.
Habitat
Found in the low intertidal and subtidal zones, typically under rocks or in crevices within kelp forests and rocky reefs, ranging from shore level to 50 meters deep.
Geographic Range
Pacific coast of North America, traditionally from Monterey Bay, California, south to Central Baja California, Mexico. Common around Cabo San Lucas.
Description
A highly polished, rounded shell with a distinctive bi-colored appearance. The dorsum features a large saddle-like patch of brown, while the sides and base are a stark, porcelain-white. The aperture is narrow and lined with small, fine teeth which help protect the animal from predators.
Key Features
Smooth, glossy texture; distinct chestnut-colored dorsal patch; white margins and base; presence of fine denticles (teeth) along both lips of the elongated aperture.
Collector Value
Low to Moderate ($5-$15 USD). It is a staple of California and Baja regional collections. Value increases with larger size, high gloss (lustre), and darker, more defined brown coloring.
Condition Notes
The specimen appears to have 'beach wear' or slight erosion, as the natural mirror-like luster of a live-taken cowrie is somewhat dulled. It is in 'Good' collector condition, likely a beach find rather than a dive-collected specimen.
Interesting Facts
The Chestnut Cowrie is the only species of cowrie native to the Californian coast. Like other cowries, the living animal has a fleshy mantle that covers and protects the shell, keeping it shiny by secreting new layers of calcium carbonate over the exterior.
Ecological Role
A scavenger and grazer, feeding on sponges, bryozoans, and occasionally algae. It serves as prey for large crabs, octopuses, and certain sea stars.
Similar Species
While unique in its primary range, it can be confused with Zonaria pyrum (Mediterranean) or smaller Luria lurida, but the specific chestnut 'saddle' is diagnostic for N. spadicea.
Beach Finding Tips
Best found after heavy winter storms at low tide in rocky areas. Look for the white 'base' side poking out of shell piles or trapped in tide pools near kelp beds.
Notes
Cabo