Smooth-edged Cockle (also known as the Egg Cockle)
Phylum: Mollusca, Class: Bivalvia, Order: Cardiida, Family: Cardiidae, Genus: Laevicardium, Species: Laevicardium laevigatum · Cardiidae (Cockle family) · Bivalve, whole shell, fan/heart shape
Species
Laevicardium laevigatum
Shell Type
Bivalve, whole shell, fan/heart shape
Family
Cardiidae (Cockle family)
Size
Approximately 1 inch in length and width, which is on the smaller to medium side. Adults typically range from 1 to 2.5 inches.
Color & Pattern
Creamy yellowish-white base color with subtle, faint brownish-orange mottling near the umbo and faint radial bands. The surface has a glossy, polished sheen.
Rarity
Common
Habitat
Shallow subtidal zones to moderately deep waters, buried just beneath sandy or muddy substrates in seagrass beds and marine flats.
Geographic Range
Western Atlantic, extending from North Carolina through the Caribbean, the Gulf of Mexico, and down to Brazil.
Description
A charming, glossy bivalve featuring a smooth, rounded outline with faint radial ribs. The umbo is prominent and slightly off-center. The glossy finish gives it a porcelain-like appearance, highly prized by casual beachcombers for its pleasing symmetry.
Key Features
Smooth, polished exterior texture with subtle radial ribs, a symmetrical oval-to-heart shape, and a glossy sheen distinguishing it from heavily textured cockles.
Collector Value
Low to moderate commercial value; it is a very popular shell for amateur crafting and general collections, usually valued at a few dollars.
Condition Notes
Good to Fine condition, largely intact with minimal wear, retaining its natural glossy sheen and original coloration without major chipping.
Interesting Facts
Cockles use a strong, muscular, sickle-shaped foot to dig rapidly into the sand and even leap away from predators like starfish.
Ecological Role
Serves as an important prey item for marine carnivores such as gastropods, rays, and crabs. They filter feed on suspended plankton, contributing to water clarity.
Similar Species
Atlantic Strawberry Cockle (Americardia media), which has much rougher, pronounced scaly ribs compared to the smoother Laevicardium species.
Beach Finding Tips
Best found by beachcombing along sandy Gulf and Caribbean beaches during low tide, especially after rough winter storms or high-surf conditions.