Atlantic Calico Scallop
Phylum: Mollusca, Class: Bivalvia, Order: Pectinida, Family: Pectinidae, Genus: Argopecten, Species: A. gibbus · Pectinidae (Scallop family) · Bivalve (Fan-shaped single valve)
Species
Argopecten gibbus
Shell Type
Bivalve (Fan-shaped single valve)
Family
Pectinidae (Scallop family)
Size
Approximately 1.5 to 2 inches in width. This is a mature specimen; typical adult range is 1 to 3 inches.
Color & Pattern
Deep pink to reddish-purple base color with faint cream-colored mottling and white flecks near the umbo. The interior (not fully visible) is likely white with matching pigment near the hinge.
Rarity
Very Common. One of the most frequently found shells on the beaches of the Carolinas.
Habitat
Shallow subtidal to deep water (up to 400 feet) on sandy or gravelly seabeds. Marine environment.
Geographic Range
Western Atlantic from North Carolina to Brazil, very common in the Gulf of Mexico and coastal waters of South Carolina and Florida.
Description
An attractive, fan-shaped bivalve with roughly 19 to 22 radiating ribs. The shell is nearly equilateral with two distinct 'ears' (auricles) at the hinge. The texture is characterized by strong, smooth radial ribs that give the margin a scalloped edge.
Key Features
Circular fan shape, roughly 20 sturdy radial ribs, nearly equal-sized auricles (ears) on either side of the hinge, and vibrant calico-like mottling.
Collector Value
Low monetary value due to abundance, but high aesthetic value for casual collectors and crafters because of the bright, varied colors.
Condition Notes
Excellent beach-found condition. The color is vivid and not sun-bleached. The ribs are sharp with minimal erosion. Collectibility grade: Fine.
Interesting Facts
Unlike many bivalves, scallops are active swimmers that use jet propulsion by clapping their valves together. They also possess dozens of tiny, bright blue eyes along the edge of their mantle to detect motion.
Ecological Role
Filter feeders that help maintain water clarity. They are a vital food source for sea stars, octopuses, and various large crustaceans.
Similar Species
Argopecten irradians (Bay Scallop) which is usually drabber (grey/brown) and has flatter ribs, whereas A. gibbus is more inflated and colorful.
Beach Finding Tips
Best found after heavy surf or storms in Myrtle Beach. Look for them in the 'shell wash' at low tide, especially in the winter months when currents bring them closer to shore.
Notes
Myrtle Beach SC