Pacific Littleneck Clam (also known as the Rock Cockle or Common Littleneck)
Phylum: Mollusca, Class: Bivalvia, Order: Venerida, Family: Veneridae, Genus: Leukoma, Species: Leukoma staminea · Veneridae (Venus Clam family) · Bivalve (two-shelled), whole shell, fan-shaped to oval morphology
Species
Leukoma staminea
Shell Type
Bivalve (two-shelled), whole shell, fan-shaped to oval morphology
Family
Veneridae (Venus Clam family)
Size
Approximately 1.5 to 2 inches in length, which is average for this species. Adults typically range from 1.5 to 3 inches.
Color & Pattern
Muted grayish-green to brownish exterior with darker radial rays and concentric growth lines. The colors appear natural with some weathering typical of intertidal specimens. Interior is typically white, sometimes with a touch of purple near the hinge.
Rarity
Very Common, frequently found while beachcombing or clamming along the Pacific Northwest coast.
Habitat
Found in intertidal and shallow subtidal zones down to about 40 feet. Prefers protected bays and estuaries buried in mixed substrates of sand, gravel, mud, and broken shell.
Geographic Range
Pacific coast of North America, ranging from the Aleutian Islands in Alaska down to San Quintin, Baja California.
Description
A sturdy, oval-to-rounded bivalve shell featuring a prominent crisscross pattern of distinct radial ribs and fine concentric growth lines. The margin is finely crenulated, and the heavy construction helps protect the animal from wave action and predators.
Key Features
Distinguished by the strong, well-defined crisscross sculptural pattern of radial ribs intersecting with concentric ridges, an internal hinge with robust teeth, and a shallow pallial sinus.
Collector Value
Low to moderate commercial value as a collector piece, primarily valued by local beachcombers and culinary gatherers rather than specialized conchologists. Usually valued under a few dollars per specimen.
Condition Notes
The specimen appears mostly intact and solid with natural weathering and minor surface erosion on the umbo. Collectibility grade is Good.
Interesting Facts
The Pacific Littleneck is an important commercial and recreational food clam. They are filter feeders and can burrow up to a few inches beneath the sediment surface.
Ecological Role
Serves as a crucial food source for various marine predators including sea otters, shorebirds, crabs, and fish. As a filter feeder, it helps clear suspended particles from the water column.
Similar Species
Manila Clam (Venerupis philippinarum), which has a more elongated rectangular shape and more pronounced posterior color patterns compared to the more rounded Littleneck.
Beach Finding Tips
Look along Pacific Northwest gravel beaches and mudflats during low tide. Look for small pairs of holes in the sand or exposed gravel bars where water squirts out when stepped on.