Atlantic Wing Oyster (also known as the Pteria or Stride Oyster)
Phylum: Mollusca, Class: Bivalvia, Order: Pteriida, Family: Pteriidae, Genus: Pteria, Species: P. colymbus · Pteriidae (Pearl Oyster and Wing Oyster family) · Bivalve, whole shell with irregular wing-like shape
Species
Pteria colymbus
Shell Type
Bivalve, whole shell with irregular wing-like shape
Family
Pteriidae (Pearl Oyster and Wing Oyster family)
Size
Approximately 2 inches in width, which is typical for a medium-sized or juvenile specimen. Adults can range up to 4 inches.
Color & Pattern
Deep purplish-brown to dark chestnut base coloration with irregular darker growth lines. The surface features contrasting white encrustations of serpulid worm tubes and barnacle remnants. The interior is pearly nacre.
Rarity
Common
Habitat
Found attached by strong byssus threads to gorgonians, sea whips, and hard substrates in shallow subtidal waters and coral reefs.
Geographic Range
Western Atlantic Ocean, including North Carolina, Florida, the Gulf of Mexico, the Caribbean Sea, and down to Brazil.
Description
An engaging dark brown bivalve shell with distinct wing-like extensions characteristic of the Pteriidae family. The rugged exterior is heavily decorated with calcareous deposits from marine encrusters, giving it a weathered, natural character. The shell exhibits strong concentric growth lamellae and a deep, somber coloration.
Key Features
Asymmetrical winged bivalve shape, elongated hinge line, deep dark brown to purple coloration, and tendency to encrust on gorgonian-dwelling habitats.
Collector Value
Low to moderate commercial value. Common in shell shops, valued more for educational displays or natural beachcombing collections than as rare specimens.
Condition Notes
Weathered natural condition with visible calcified worm tubes and encrusting organisms on the exterior. The shell structure is intact. Grade: Good.
Interesting Facts
Pteria species are closely related to true pearl oysters and are capable of producing pearls, though rarely of gem quality. They rely on tough byssus threads to anchor themselves securely to swaying sea whips in high-energy currents.
Ecological Role
Acts as a filter feeder, helping to clear particulate matter from the water column. Serves as a micro-habitat for various epibiotic organisms like serpulid worms and bryozoans.
Similar Species
Pteria sterna (Pacific Wing Oyster) - distinguished by geographic location and slightly brighter iridescent coloration.
Beach Finding Tips
Look for these shells washed up near coral reef tracts or attached to washed-up sea whips and gorgonians following heavy storms in the Caribbean or Florida keys.