Atlantic Deep-Sea Scallop or Purplish Atlantic Calico Scallop (commonly referred to simply as a Calico Scallop)
Phylum: Mollusca, Class: Bivalvia, Order: Pectinida, Family: Pectinidae, Genus: Argopecten, Species: Argopecten gibbus · Pectinidae (Scallop family) · Bivalve (two-shelled), whole individual valve, fan-shaped
Species
Argopecten gibbus
Shell Type
Bivalve (two-shelled), whole individual valve, fan-shaped
Family
Pectinidae (Scallop family)
Size
Approximately 1.5 to 2 inches in diameter, which is average for an adult specimen of this species. Adults typically range between 1.5 and 2.5 inches.
Color & Pattern
Displays a vibrant mottled pattern featuring shades of deep purple, lavender, and white. The coloration is entirely natural, showing classic calico-style streaks and radial bands radiating from the umbo toward the ventral margin. The interior shows matching purple tinges within the white nacre.
Rarity
Common, frequently found by beachcombers along the southeastern coast of the United States and the Gulf of Mexico.
Habitat
Inhabits shallow marine waters, commonly found on sandy, shelly, or gravelly bottoms in offshore beds, typically ranging from the intertidal zone down to depths of about 150 feet.
Geographic Range
Western Atlantic Ocean, extending from North Carolina through Florida, the Gulf of Mexico, the Caribbean, and south to parts of South America.
Description
A classic, charming fan-shaped bivalve with roughly 18 to 22 well-defined radial ribs. The surface texture is finely striated, featuring a slightly asymmetrical auricle (ears) at the hinge line. The shell exhibits an attractive purple-and-white color palette with distinct zig-zag or mottled patterns that make it a favorite for shell crafts and beginner collections.
Key Features
Symmetrical fan shape with roughly 20 rounded radial ribs, unequal auricles at the hinge typical of the genus Argopecten, and distinctive purple mottled coloration.
Collector Value
Low to moderate commercial value, but highly desirable for casual beachcombers and crafters. Specimens with exceptionally bright purple or pink hues command slightly more interest among color-form collectors.
Condition Notes
Good condition. The valve is mostly intact with minor wear along the ventral margin. Colors remain bright and natural with minimal sun-bleaching. Collectibility grade is Fine.
Interesting Facts
Unlike many bivalves that burrow or remain sessile, scallops like Argopecten gibbus can swim actively by rapidly clapping their valves together to expel water, allowing them to escape predators. They also possess dozens of tiny, bright blue eyes along the mantle edge that can detect light and motion.
Ecological Role
Scallops are filter feeders, playing an important role in maintaining water clarity by consuming phytoplankton and suspended organic particles. They serve as an important food source for bottom-feeding fish, rays, sea stars, and octopuses.
Similar Species
Atlantic Bay Scallop (Argopecten irradians), which tends to be slightly larger and slightly more inflated with flatter ribs, and the Rough Scallop (Aequipecten muscosus), which has more pronounced, scaly ribs.
Beach Finding Tips
Best found by beachcombing along sandy ocean-facing beaches after storms or strong onshore winds. Look along the high tide line where shell drift accumulates.