Cockle (specifically Great Heart Cockle or similar Cardiidae species)
Phylum Mollusca, Class Bivalvia, Order Cardiida, Family Cardiidae, Genus Trachycardium, Species egmontianum · Cardiidae (Cockle family) · Bivalve (two-shelled clam), whole single valve, fan/heart shape
Species
Trachycardium egmontianum or related species in the family Cardiidae
Shell Type
Bivalve (two-shelled clam), whole single valve, fan/heart shape
Family
Cardiidae (Cockle family)
Size
Approximately 1.5 to 2 inches in width, typical for many medium-sized cockle species which generally range from 1 to 3 inches.
Color & Pattern
Muted grayish-brown exterior with earthy undertones, showing natural weathering and standard pigmentation for beach-worn specimens. The interior is not visible in this view.
Rarity
Common to Very Common
Habitat
Shallow marine waters, typically found burrowing in sandy or muddy substrates in intertidal to shallow subtidal zones.
Geographic Range
Widely distributed globally across temperate and tropical marine waters, with many common Atlantic and Gulf of Mexico species.
Description
A sturdy, symmetrical bivalve shell featuring prominent, deeply incised radial ribs running from the umbo (beak) to the margin. The surface texture is rough and scaly due to the strong ribbing, creating a scalloped edge along the ventral margin.
Key Features
Strong radial ribs, inflated heart-shaped profile when both valves are joined, and crenulated margins.
Collector Value
Low to moderate commercial value; commonly collected by beachcombers worldwide rather than heavily traded among high-end collectors.
Condition Notes
Fair to Good condition; shows some natural weathering and wear on the surface, but the structural integrity of the valve is intact.
Interesting Facts
Cockles are capable of using their muscular, hatchet-shaped foot to jump or leap away from predators such as starfish.
Ecological Role
Cockles serve as an important food source for many marine predators, including fish, birds, and sea stars, and help filter nutrients from the water column.
Similar Species
Pectinidae (scallops), which are generally flatter with distinct 'ears' near the hinge, whereas cockles are more inflated.
Beach Finding Tips
Look along sandy beaches following storm activity or at low tide, scanning the surf line where heavy wave action deposits sturdy bivalve shells.