Calico Scallop
Phylum: Mollusca, Class: Bivalvia, Order: Pectinida, Family: Pectinidae, Genus: Argopecten, Species: A. gibbus · Pectinidae (Scallop family) · Bivalve (two-shelled), fan-shaped, whole individual valve
Species
Argopecten gibbus
Shell Type
Bivalve (two-shelled), fan-shaped, whole individual valve
Family
Pectinidae (Scallop family)
Size
Approximately 1.5 to 2 inches in width, which is average for this species. Adults typically range from 1.5 to 2.5 inches.
Color & Pattern
A vibrant mottled and patterned combination of dark reddish-brown, chocolate, and cream spots or streaks radiating along the prominent ribs against a lighter background. Colors appear entirely natural and glossy.
Rarity
Common
Habitat
Shallow marine waters, typically found on sandy bottoms, seagrass beds, and offshore shoals ranging from shallow subtidal zones down to depths of several hundred feet.
Geographic Range
Western Atlantic Ocean, extending from North Carolina down through the Florida coasts, the Gulf of Mexico, and the Caribbean Sea.
Description
An attractive, roughly symmetrical fan-shaped bivalve featuring strong, rounded radial ribs extending from the umbo to the margin. The margins are scalloped and crenulated, showing rich, contrasting patterns of brown and white.
Key Features
Rounded radial ribs (typically around 18-22), unequal 'ears' or auricles at the hinge line, and a distinctively mottled 'calico' color pattern.
Collector Value
Inexpensive and widely available, though sought after by beachcombers for their bright, colorful patterns. Generally valued at a few dollars per specimen.
Condition Notes
Fine condition with intact margins, strong color retention, and minimal wear around the umbo. A solid collectible grade specimen.
Interesting Facts
Unlike many bivalves, calico scallops are capable of swimming by rapidly clapping their valves together to expel water, allowing them to escape predators like starfish.
Ecological Role
Serves as an important prey item for various marine predators including fish, rays, and sea stars, contributing to the coastal marine food web.
Similar Species
Atlantic Bay Scallop (Argopecten irradians), which tends to be slightly more rounded with squarer ribs, and the Rough Scallop.
Beach Finding Tips
Look along high tide lines on Gulf and Atlantic beaches of Florida, especially after storms or heavy winds.