Zigzag Scallop / Calico Scallop
Phylum: Mollusca, Class: Bivalvia, Order: Pectinida, Family: Pectinidae, Genus: Argopecten, Species: Argopecten gibbus · Pectinidae (Scallop family) · Bivalve (two-shelled clam), whole single valve, fan shape
Species
Argopecten gibbus
Shell Type
Bivalve (two-shelled clam), whole single valve, fan shape
Family
Pectinidae (Scallop family)
Size
Approximately 1 inch in length and width, which is typical for a mature specimen of this species. Adults generally range from 1 to 1.5 inches.
Color & Pattern
Cream to whitish base color adorned with distinct reddish-brown zigzag or mottled patterns radiating from the umbo. Colors appear natural and well-preserved.
Rarity
Common, frequently found washed ashore on beaches within its native range.
Habitat
Found in marine environments, specifically in shallow subtidal waters down to moderate depths, inhabiting sandy or shelly substrates, often amongst seagrass beds.
Geographic Range
Western Atlantic Ocean, ranging from North Carolina down through the Gulf of Mexico, the Caribbean, and south to Brazil.
Description
A charming and compact bivalve with a classic fan-shaped morphology. The exterior features well-defined radial ribs crossed by fine growth lines, showcasing an attractive and complex zigzag pattern in reddish-brown over a pale background.
Key Features
Equilateral fan shape, well-developed radial ribs, distinct asymmetrical ears at the hinge, and characteristic zigzag or flame-like reddish color patterns.
Collector Value
Low to moderate commercial value; popular among casual beachcombers and beginner shell collectors, often used in shell crafts rather than high-end scientific collections.
Condition Notes
The shell appears to be a single intact valve in good overall condition with clear patterns and minimal wear, grading as 'Good' to 'Fine'.
Interesting Facts
Scallops are unique among bivalves for their ability to swim actively by rapidly clapping their valves together to expel water, and they possess a row of dozens of tiny, bright blue eyes along the edge of their mantle.
Ecological Role
Serves as an important prey item for various marine predators including fish, rays, and sea stars, contributing to the benthic food web in shallow coastal ecosystems.
Similar Species
Atlantic Bay Scallop (Argopecten irradians), which is typically slightly larger with shallower ribs and a more rounded profile.
Beach Finding Tips
Best found by beachcombing along high-tide lines on sandy beaches in Florida and the Gulf of Mexico, particularly after storms or heavy wave action.