Atlantic Calico Scallop (also known as Calico Scallop)
Phylum: Mollusca, Class: Bivalvia, Order: Pectinida, Family: Pectinidae, Genus: Argopecten, Species: Argopecten gibbus · Pectinidae (Scallop family) · Bivalve (two-shelled), whole shell, fan-shaped
Species
Argopecten gibbus
Shell Type
Bivalve (two-shelled), whole shell, fan-shaped
Family
Pectinidae (Scallop family)
Size
Approximately 1.5 to 2 inches in length and width, which is average for this species. Adults typically range from 1.5 to 2.5 inches.
Color & Pattern
Vibrant reddish-brown and orange mottled patterns radiating outward in zigzag or chevron streaks against a lighter background. Colors appear entirely natural and well-preserved with no significant sun-bleaching.
Rarity
Common, frequently found by beachcombers in suitable regions, especially after storms.
Habitat
Shallow subtidal marine waters, typically found on sandy bottoms or among seagrass beds in depths ranging from a few feet down to 150 feet.
Geographic Range
Western Atlantic Ocean, ranging from North Carolina down through Florida, the Gulf of Mexico, and the Caribbean Sea.
Description
A classic fan-shaped bivalve with distinct, prominent radiating ribs and characteristic asymmetrical ears at the hinge line. The margins are scalloped to match the external ribs, creating a deeply fluted edge.
Key Features
Prominent, rounded radiating ribs (usually numbering around 18 to 22), unequal ears (auricles) at the hinge, and an inflated, convex valve structure.
Collector Value
Low to moderate commercial value, highly popular with casual beachcombers and crafters due to their attractive colorful patterns, but readily available.
Condition Notes
Good to Fine condition, displaying bright natural coloration and intact margins with very minor wear at the beak area.
Interesting Facts
Scallops are among the few bivalves that can swim. By rapidly clapping their valves together, they expel water and jet-propel themselves away from predators like starfish.
Ecological Role
Acts as an important filter feeder in coastal marine ecosystems and serves as a vital food source for numerous fish, rays, crabs, and sea turtles.
Similar Species
Atlantic Bay Scallop (Argopecten irradians), which tends to have a more compressed shell, flatter ribs, and prefers shallower estuarine waters.
Beach Finding Tips
Look along shell-rich Atlantic and Gulf coast beaches, particularly at low tide or immediately following rough weather and high surf.