Yellow Cockle (also known as the Egg Cockle)
Phylum: Mollusca, Class: Bivalvia, Order: Cardiida, Family: Cardiidae, Genus: Laevicardium, Species: Laevicardium laevigatum · Cardiidae (Cockle family) · Bivalve (two-shelled), whole single valve, fan/heart-shaped
Species
Laevicardium laevigatum
Shell Type
Bivalve (two-shelled), whole single valve, fan/heart-shaped
Family
Cardiidae (Cockle family)
Size
Approximately 1 inch, which is smaller than average; adults typically range from 1.5 to 2.5 inches.
Color & Pattern
Pale creamy yellow base with subtle darker brown speckles or dashes aligned along specific radial ribs, creating a broken band pattern. Colors appear mostly natural with slight weathering.
Rarity
Common
Habitat
Shallow subtidal waters to moderate depths, living buried just beneath the surface of clean sand or sandy-mud bottoms.
Geographic Range
Western Atlantic, extending from North Carolina through the Caribbean, Gulf of Mexico, and down to Brazil.
Description
A smooth yet ribbed, rounded bivalve shell with a symmetrical, inflated profile. The exterior features fine, radiating ribs crossed by delicate growth lines, and the margin is finely crenulated.
Key Features
Smooth overall appearance with subtle radial ribs, slightly asymmetrical oval-to-heart shape when viewed together, and distinctive small dark markings along the posterior slope.
Collector Value
Inexpensive and widely accessible. Highly polished variants or pristine paired valves hold minor appeal, but single beach-worn valves are very common and mostly of educational value.
Condition Notes
Good condition. Intact single valve with good retention of original coloration and markings, minor natural wear on the margins, graded as Fine collectibility.
Interesting Facts
Cockles are capable of using their muscular, hatchet-shaped foot to dig rapidly into the sand or even leap away from potential predators like starfish.
Ecological Role
Serves as an important prey species for carnivorous snails, crabs, and bottom-feeding fish, contributing to the benthic food web.
Similar Species
Atlantic Strawberry Cockle (Americardia media), which has much rougher, more pronounced scaly ribs compared to the smoother surface of Laevicardium laevigatum.
Beach Finding Tips
Look along sandy ocean-facing beaches after storms or high tides, particularly near tidal inlets and shallow sandbars where surf deposits shell debris.