Hard Clam, Northern Quahog, Littleneck (small), Cherrystone (medium), Chowder Clam (large)
Phylum: Mollusca, Class: Bivalvia, Order: Venerida, Family: Veneridae, Genus: Mercenaria, Species: M. mercenaria · Veneridae (Venus Clams) · Bivalve (single valve shown, likely the left valve). Shape is ovate-trigonal (heart-shaped near the umbo).
Species
Mercenaria mercenaria
Shell Type
Bivalve (single valve shown, likely the left valve). Shape is ovate-trigonal (heart-shaped near the umbo).
Family
Veneridae (Venus Clams)
Size
Approximately 3.5 to 4 inches in length. This is a mature adult 'Chowder' size specimen. Species typically ranges from 1 to 5 inches.
Color & Pattern
Off-white to greyish-tan exterior with concentric growth rings. Some areas show a bluish-grey mineral staining from burial in anaerobic sediment. Interior (not visible) usually features a distinctive deep purple patch near the posterior end.
Rarity
Very Common. One of the most frequently encountered shells on the beaches of the US Atlantic coast.
Habitat
Found in the intertidal and subtidal zones, typically buried in sand or muddy substrates in bays, estuaries, and along the open coast.
Geographic Range
Western Atlantic coast, from the Gulf of St. Lawrence in Canada down to Florida and the Gulf of Mexico. Very common in South Carolina.
Description
A thick, heavy, and very sturdy shell with a prominent, forward-leaning beak (umbo). The exterior is sculpted with numerous closely spaced concentric growth lines which provide a rough texture especially near the margins. The shell is notably inflated (convex), making it quite deep.
Key Features
Heaviness/thickness of the shell, heart-shaped profile when viewed from the side, and the characteristic lack of radial ribs (only concentric lines present). The internal purple staining (Wampum) is the defining diagnostic trait if the shell were flipped.
Collector Value
Low monetary value due to its extreme abundance, but high educational and historical value. Large, well-preserved valves or matched pairs with deep purple interiors are preferred by hobbyists.
Condition Notes
Good condition. The shell shows some minor 'beach wear' or erosion on the growth lines, typical for a surf-tossed specimen. It is a single valve rather than a paired 'hinged' set. No visible predation holes.
Interesting Facts
The purple part of this shell was used by Native Americans (Algonquian tribes) to create beads for 'Wampum' belts, which served as currency and recorded history. The name 'Mercenaria' is derived from the Latin word for wages or commerce.
Ecological Role
Filter feeder that improves water quality by straining plankton and organic matter. They are a primary food source for whelks, rays, and humans. They are commercially farmed and highly regulated.
Similar Species
Southern Quahog (Mercenaria campechiensis) which is usually larger, heavier, and lacks the purple staining inside.
Beach Finding Tips
Best found after storms or during low tide at Myrtle Beach. Look for them in the 'shell hash' lines or near the water's edge where the tide pulls back. They are often partially buried.
Notes
Myrtle Beach SC