Calico Scallop (also known as the Dwarf Calico Scallop)
Phylum: Mollusca, Class: Bivalvia, Order: Pectinida, Family: Pectinidae, Genus: Argopecten, Species: A. gibbus · Pectinidae (Scallop family) · Bivalve (two-shelled clam), whole shell, fan or disc-shaped
Species
Argopecten gibbus
Shell Type
Bivalve (two-shelled clam), whole shell, fan or disc-shaped
Family
Pectinidae (Scallop family)
Size
Approximately 1 inch in diameter, which is typical for an adult of this species. Adults generally range from 0.75 to 1.5 inches.
Color & Pattern
Pale off-white or cream base color with faint, subtle pinkish or brownish spots and mottling. The colors appear somewhat sun-bleached, typical of beach-worn specimens.
Rarity
Very Common
Habitat
Found in shallow marine waters, typically living on sandy or shelly bottoms, often among seagrass beds in depths ranging from the low intertidal zone down to about 150 feet.
Geographic Range
Western Atlantic Ocean, ranging from North Carolina down through Florida, the Gulf of Mexico, the Caribbean, and south to the West Indies.
Description
A charming, small bivalve shell with a classic fan-shaped profile featuring numerous distinct, rounded radial ribs and slightly unequal auricles (ears) at the hinge. The margin is scalloped, matching the external ribs.
Key Features
Symmetrical fan shape, numerous rounded radial ribs, and the distinctive unequal 'ears' (auricles) flanking the umbo at the hinge line.
Collector Value
Low to moderate value. While widely collected and very common, they are popular in shell crafts and beginner collections. Generally valued from a few cents to a couple of dollars depending on condition and color vibrancy.
Condition Notes
Good condition. The specimen is intact with minor natural wear along the margins and slight fading of coloration, typical of a beach find. Grade: Good.
Interesting Facts
Scallops are among the few bivalves that can actively swim by clapping their valves together to expel water, propelling themselves through the water column to escape predators.
Ecological Role
Serves as an important prey item for various marine predators including sea stars, crabs, fish, and octopuses. They filter feed on phytoplankton, helping to maintain water clarity.
Similar Species
Atlantic Bay Scallop (Argopecten irradians), which tends to be slightly larger with flatter ribs and is found in shallower estuarine environments.
Beach Finding Tips
Look along sandy ocean-facing beaches after high tide or stormy weather, particularly in the southeastern United States and Florida, where whole valves often wash ashore.