Atlantic Strawberry Cockle
Phylum: Mollusca, Class: Bivalvia, Order: Cardiida, Family: Cardiidae, Genus: Americardia, Species: A. media · Cardiidae (Cockle family) · Bivalve (two-shelled mollusk); single valve shown (likely the left valve). The shape is roughly square or boxy with a distinct posterior slope.
Species
Americardia media
Shell Type
Bivalve (two-shelled mollusk); single valve shown (likely the left valve). The shape is roughly square or boxy with a distinct posterior slope.
Family
Cardiidae (Cockle family)
Size
Approximately 0.75 to 1 inch (19-25mm). This is average for a mature specimen, as the species typically reaches 1 to 1.5 inches.
Color & Pattern
Cream to off-white base color with heavy, irregular mottling and chevron-like patterns in reddish-brown or rusty orange. The interior (not visible but characteristic) is typically white, sometimes with yellow or orange tinting near the umbo.
Rarity
Common. These are frequently found on beaches throughout the Caribbean and Florida, particularly after storms or high tides.
Habitat
Shallow marine waters, ranging from the intertidal zone to depths of about 60 meters. Prefers sandy or gravelly substrates where it can burrow just below the surface.
Geographic Range
Western Atlantic; ranging from Cape Hatteras, North Carolina, south through the Gulf of Mexico, Caribbean Sea, and Brazil.
Description
A thick, robust, and moderately small shell with a distinctive boxy or 'quadrate' profile. The shell features approximately 30-36 strong, scaly radial ribs. The posterior end is noticeably flattened or 'truncated,' a key diagnostic feature of the genus Americardia. The texture is rough to the touch due to the fine scales on the ribs.
Key Features
The most defining feature is the sharply angled posterior slope giving it a square appearance. Unlike other cockles, the ribs on this species are cross-sculptured with fine, tile-like scales.
Collector Value
Low monetary value ($1-$5) due to its abundance, but highly desirable for thematic collections (such as 'Cockles of the World') due to its attractive patterns and unique geometric shape.
Condition Notes
The specimen appears to be in 'Fine' to 'Good' condition. It retains strong pigmentation, though there is minor edge wear and some smoothing of the rib scales, suggesting it spent some time tumbling in the surf before being found.
Interesting Facts
Like many cockles, the living animal has a strong, muscular foot that it can use to 'jump' across the seafloor to escape predators like sea stars or snails. The 'Strawberry' name comes from its rounded, reddish mottled appearance when both valves are closed.
Ecological Role
Infaunal filter feeders that help clarify water by straining plankton and organic detritus. They serve as a vital food source for shorebirds, crabs, and various species of bottom-dwelling fish.
Similar Species
Trigoniocardia antillarum (Antillean Strawberry Cockle), which is usually smaller and has fewer ribs; and Americardia guppyi, which is typically found in deeper water and has more delicate sculpture.
Beach Finding Tips
The best time to find these is at low tide on sandy beaches near seagrass beds. Look for the distinctive square shape and reddish spots among shell drift lines. They are common in the Florida Keys and the Bahamas.