Yellow Cockle, Prickly Cockle, Common Egg Cockle
Phylum: Mollusca, Class: Bivalvia, Order: Cardiida, Family: Cardiidae, Genus: Dachycardium, Species: Dachycardium muricatum · Cardiidae (Cockle family) · Bivalve (Single valve). Specifically a heart-shaped clam shell with a fan-like radial structure.
Species
Divalinga quadrisulcata (likely) or Dachycardium muricatum
Shell Type
Bivalve (Single valve). Specifically a heart-shaped clam shell with a fan-like radial structure.
Family
Cardiidae (Cockle family)
Size
Approximately 1.5 - 2 inches (3.8 - 5 cm). This is a medium-sized specimen for this species, which can reach up to 3 inches.
Color & Pattern
Base color is an off-white to cream. The radial ribs show distinct alternating bands of yellowish-tan and light brown towards the margins. The interior (unseen but implied) is usually white or pale yellow. The pattern follows the scalloped ribs with darker pigmentation concentrated on the elevated scales.
Rarity
Common. These are frequently found on beaches after storms or high tides throughout the Southeastern United States and Caribbean.
Habitat
Shallow water marine environments, typically found in sandy bottoms from the intertidal zone to depths of about 30 meters. They prefer high-salinity coastal waters.
Geographic Range
Western Atlantic, ranging from North Carolina, USA, through the Gulf of Mexico and Caribbean to Brazil.
Description
A robust, convex valve characterized by 30-40 strong radial ribs. Each rib is adorned with small, transverse scales or 'prickles' that are more pronounced at the posterior and anterior margins. The shell is nearly circular but slightly elongated towards the beak (umbo), which is central and curved.
Key Features
The most distinguishing features are the sharp, scale-like serrations on the radial ribs and the classic 'heart shape' visible when both valves are joined. The interlocking scalloped margin is also highly characteristic.
Collector Value
Minimal monetary value ($1-$5) due to its abundance, but highly desirable for decorative crafts and beginner collections because of its symmetry and distinct texture.
Condition Notes
Good condition. It appears to be a beach-warn specimen with some sand and salt crystal buildup. The ribs are mostly intact, though some of the finer prickles have been eroded by wave action. Grade: Fine.
Interesting Facts
Cockles have a very strong, saltatory foot that allows them to 'jump' across the sea floor to escape predators like starfish and snails. Historically, various species of cockles have been used as a food source in Europe and the Americas for centuries.
Ecological Role
Suspension feeders that filter plankton from the water column. They play a vital role in cleaning coastal waters and serve as a primary food source for shorebirds, rays, and crabs.
Similar Species
Trachycardium egmontianum (Florida Prickly Cockle), which typically has more colorful purple or reddish interiors and slightly different scale arrangements.
Beach Finding Tips
Look along the wrack line (the line of debris left by high tide) after a storm. They are most easily found during low tide in tropical sandy beaches where the surf is moderate.