Tiger Lucine or Giant Cockle (specifically a Cardita or similar large bivalve, likely an Ovoid Cockle or Egg Cockle)
Phylum: Mollusca, Class: Bivalvia, Order: Cardiida, Family: Cardiidae, Genus: Laevicardium, Species: Laevicardium laevigatum (Egg Cockle) · Cardiidae (Cockle family) · Bivalve (two-shelled), whole closed shell, oval to slightly inflated shape
Species
Trachycardium egmontianum or similar bivalve species (Confidence level: High for bivalve family Cardiidae, moderate for exact species without seeing the interior hinge and radial ribs more clearly)
Shell Type
Bivalve (two-shelled), whole closed shell, oval to slightly inflated shape
Family
Cardiidae (Cockle family)
Size
Approximately 3 inches in length. This is a medium to large specimen; typical adults of this species range from 2 to 4 inches.
Color & Pattern
Smooth, glossy exterior with pale creamy yellow to soft butter-yellow tones, featuring subtle darker yellowish-orange growth bands radiating across the surface. Colors appear completely natural and well-preserved with a healthy sheen.
Rarity
Common, frequently collected intact by beachcombers in favorable regions after storms or during extreme low tides.
Habitat
Shallow subtidal waters to intertidal zones, buried just beneath the surface in clean sandy bottoms or fine sand bars in marine environments.
Geographic Range
Warm temperate to tropical waters, commonly found throughout the Western Atlantic, Caribbean Sea, and the Gulf of Mexico.
Description
An exceptionally smooth and symmetrically inflated bivalve shell with an attractive, glossy porcelain-like finish. The margins fit together tightly, and the gentle curved profile displays a lovely pale yellow coloration accented by delicate, faint growth lines that accentuate its rounded, egg-like contour.
Key Features
Smooth, polished exterior surface lacking the deep, prominent heavy ribs of typical cockles, symmetrical rounded profile, and a closed bivalve margin with a subtle heart-shaped outline when viewed from the end.
Collector Value
Low to moderate value. While widely available and affordable, pristine, high-gloss specimens with rich natural pastel colors are always popular additions to beginner and intermediate shell collections.
Condition Notes
Gem to Fine condition. The shell is fully intact, closed, retaining its natural glossy sheen and soft coloration with no significant chips, cracks, or heavy wear.
Interesting Facts
Cockles are capable of rapid movement using a muscular, axe-shaped foot, which they use not only to burrow into the sand with surprising speed but also to leap away from approaching predatory starfish.
Ecological Role
Serves as an important prey item for various marine predators including carnivorous snails, rays, and sea stars. As filter feeders, they help maintain water clarity by consuming suspended organic particles and plankton.
Similar Species
Other members of the Cardiidae family, such as the Yellow Cockle (Trachycardium muricatum), which typically features much more pronounced and rough radial ribs compared to the smooth surface of the Egg Cockle.
Beach Finding Tips
Look along sandy beaches during low tide, particularly after strong offshore winds or storms have churned up the subtidal sandbars where these bivalves burrow.