Turkey Wing (also known as the Turkey Wing Ark)
Phylum: Mollusca, Class: Bivalvia, Order: Arcida, Family: Arcidae, Genus: Arca, Species: Arca zebra · Arcidae (Ark family) · Bivalve (Two-shelled); Single valve (left); Boat/Box-shaped
Species
Arca zebra
Shell Type
Bivalve (Two-shelled); Single valve (left); Boat/Box-shaped
Family
Arcidae (Ark family)
Size
Approximately 1.5 - 2 inches in length. A typical adult range is 2-4 inches, suggesting this is a sub-adult or slightly weathered specimen.
Color & Pattern
Featuring distinct reddish-brown to dark chocolate 'zebra' stripes on a cream or tan background. The stripes are bold, jagged, and run diagonally across the fine radial ribs. The interior (not visible but characteristic) would be white to purplish with a dark dash in the center.
Rarity
Common; frequently found on North Carolina beaches after storms or heavy surf, though often as single valves rather than paired 'wings'.
Habitat
Marine; typically found attached to rocks, coral, or other shells using a bypass (strong threads) in shallow subtidal waters down to 20 meters. They prefer areas with good water flow.
Geographic Range
Western Atlantic, ranging from North Carolina (including Holden Beach) down to Florida, the Caribbean, and south to Brazil.
Description
An elongated, rectangular bivalve with a distinct 'wing' shape. The shell features a wide, flat hinge area and a prominent umbo (beak) located near the anterior end. Its surface is covered in numerous fine radial ribs that intersect with concentric growth lines, creating a slightly beaded texture. The most striking feature is the diagonal brown banding resembling a bird's feathers or zebra stripes.
Key Features
Distinctive rectangular/winged shape; straight, long hinge line; bold diagonal brown stripes; fine radial ribbing that feels rough to the touch; bypass notch on the ventral margin.
Collector Value
Modest; while common, they are highly desirable for beginners and craft artists due to their beautiful patterns. Paired valves (both halves attached) are much more valuable to serious collectors than single valves.
Condition Notes
Good; the shell displays strong coloration and clear patterns. There is some minor 'beach wear' on the edges and umbo area, and the periostracum (the fuzzy outer skin) has been naturally cleaned off by ocean action. Collectibility grade: Fine.
Interesting Facts
The name 'Turkey Wing' comes from its resemblance to a spread bird wing when both valves are open. It attaches itself so firmly to the substrate using its byssal threads that it can be difficult for predators to dislodge. Historically, they have been harvested for food in the Caribbean.
Ecological Role
Suspension feeder; helps filter seawater by consuming plankton and organic particles. They serve as a food source for bottom-dwelling predators like whelks, crabs, and rays.
Similar Species
Mossy Ark (Arca imbricata), which lacks the bold zebra stripes and is typically covered in a thick, hairy periostracum; and the Ponderous Ark (Noetia ponderosa), which is much thicker and more heart-shaped.
Beach Finding Tips
Best found at low tide or after a coastal storm. On Holden Beach, look near the wrack line (seaweed line) where smaller debris accumulates. Because they are often attached to offshore structures, a strong onshore wind often brings them to the sand.
Notes
Holden Beach, NC