Cockle Shell (Common Cockle)
Phylum: Mollusca, Class: Bivalvia, Order: Cardiida, Family: Cardiidae, Genus: Cerastoderma, Species: Cerastoderma edule · Cardiidae (Cockle family) · Bivalve, whole shell, fan-shaped
Species
Cerastoderma edule
Shell Type
Bivalve, whole shell, fan-shaped
Family
Cardiidae (Cockle family)
Size
Approximately 1.5 to 2 inches, which is standard for an adult specimen of this species. Typical adults range between 1 and 2.5 inches.
Color & Pattern
Uniform silvery-white appearance, suggesting it has been spray-painted or treated with a craft finish rather than showing natural pigmentation, which normally ranges from off-white to yellowish-brown with darker concentric growth rings.
Rarity
Very Common in its native European coastal habitats, though this specific modified finish is artificially altered.
Habitat
Inhabits shallow marine and estuarine waters, living buried just beneath the surface of intertidal mudflats and fine sandy beaches.
Geographic Range
Northeastern Atlantic, from the Barents Sea down to northwest Africa, including the Baltic Sea, North Sea, and Mediterranean Sea.
Description
A symmetrical, heart-shaped bivalve when viewed from the side, featuring strong, radiating ribs and fine concentric growth lines that create a textured, interlocking edge along the ventral margin.
Key Features
Prominent, regular radiating ribs (typically 22 to 28), equilateral rounded-triangular or heart-shaped profile, and a deeply toothed inner margin.
Collector Value
Low monetary value for natural specimens due to abundance; this specific painted version holds value primarily for decorative or craft purposes rather than conchological collections.
Condition Notes
The shell appears structurally intact and solid, but it has been artificially coated in a metallic silver paint or glitter spray, grading its collectibility as a craft item rather than a natural specimen.
Interesting Facts
Cockles are capable of leaping using their muscular foot to escape predators such as starfish and predatory snails, and they are commercially harvested for human consumption across Europe.
Ecological Role
Acts as an important filter feeder helping to clear coastal waters, serves as a vital food source for wading birds and fish, and bioturbates surface sediments.
Similar Species
Acanthocardia tuberculata (Spiny Cockle), which features distinct spiny tubercles along the ribs, and Laevicardium mortoni (Morton's Egg Cockle), which is smoother and glossier.
Beach Finding Tips
Look along intertidal sand and mud flats during extremely low tides, searching for small spurting holes or tiny V-shaped indents in the sand where the siphons reach the surface.