Pacific Strawberry Cockle or Hairy Cockle
Phylum: Mollusca, Class: Bivalvia, Order: Cardiida, Family: Cardiidae, Genus: Fragum, Species: Fragum unedo · Cardiidae (Cockle family) · Bivalve (two-shelled), whole shell, sub-globular heart-shaped fan
Species
Fragum unedo
Shell Type
Bivalve (two-shelled), whole shell, sub-globular heart-shaped fan
Family
Cardiidae (Cockle family)
Size
Approximately 1.25 inches, which is slightly smaller than average for the species. Adults typically range from 1 to 2.5 inches.
Color & Pattern
Base color is off-white to creamy beige with distinctive rows of reddish-brown or orange-brown square spots or blotches aligned along the prominent radial ribs. Colors appear natural and well-preserved.
Rarity
Common, frequently found in suitable tropical reef and sandflat habitats throughout its native range.
Habitat
Shallow subtidal and intertidal zones, typically found buried just beneath the surface in clean sandy substrates, coral sand, and seagrass beds in warm tropical waters.
Geographic Range
Indo-West Pacific region, ranging from East Africa and the Red Sea across the Indian Ocean to Southeast Asia, Indonesia, Australia, and throughout Polynesia including the Hawaiian Islands.
Description
This charming bivalve features a robust, inflated, heart-shaped profile when viewed from the side, characterized by strong, prominent radial ribs crossed by fine concentric growth lines that create a beaded or scaly texture. The margin is deeply serrated to match the external ribbing, interlocking tightly when closed.
Key Features
Rounded, inflated shape with strong radial ribs studded with bead-like nodes, and distinctive reddish-brown square spots arranged in interrupted bands along the ribs.
Collector Value
Low to moderate commercial value. Popular among beginner and intermediate shell collectors for its attractive geometry and spotted patterns, commonly found in shell shops.
Condition Notes
Good to Fine condition. The shell is structurally intact with minimal wear on the ribs, preserving its original coloration and bead-like sculptural details.
Interesting Facts
Cockles possess a strong, muscular, axe-shaped foot that they use not only to burrow rapidly into the sand but also to leap away from predators such as predatory sea snails and starfish.
Ecological Role
Acts as a benthic filter feeder, consuming microscopic plankton and organic particles from the water column, thereby helping to maintain water clarity. Serves as an important prey item for various marine carnivores.
Similar Species
Fragum fragum (Strawberry Cockle), which tends to be more distinctly oblong and features more vivid strawberry-red markings between the ribs.
Beach Finding Tips
Look along tropical sandy beaches and reef flats at low tide, particularly after storms or heavy wave action that unearths buried bivalves from the shallow subtidal zones.
Notes
Laie oahu