Atlantic Deep-Sea Scallop (also known as Giant Scallop)
Phylum: Mollusca, Class: Bivalvia, Order: Pectinida, Family: Pectinidae, Genus: Placopecten, Species: P. magellanicus · Pectinidae (Scallop family) · Bivalve (two-shelled), whole shell, fan/disc shape
Species
Placopecten magellanicus
Shell Type
Bivalve (two-shelled), whole shell, fan/disc shape
Family
Pectinidae (Scallop family)
Size
Approximately 2 to 3 inches in the visible specimens, which is typical for younger individuals or specific regional populations; adults can reach up to 6 to 8 inches in diameter.
Color & Pattern
Smooth to finely ribbed exterior with a creamy white to pale pinkish-tan base color, featuring subtle darker peach or orange tones near the umbo (hinge area). The surface has a natural, slightly glossy sheen. The interior is smooth and pearly white.
Rarity
Common
Habitat
Found on sandy, gravelly, or shelly bottoms in cold marine waters, typically ranging from the low intertidal zone down to depths of over 100 meters on the continental shelf.
Geographic Range
Northwest Atlantic Ocean, ranging from Labrador and Newfoundland down along the eastern coast of the United States to North Carolina.
Description
These attractive bivalve shells exhibit a classic fan shape with smooth, rounded margins and subtle radial ribs concentrated near the umbo. The surface has been naturally tumbled or polished, highlighting the smooth texture and warm gradient from creamy white to soft peach near the beak. The valves are relatively sturdy with symmetrical ears.
Key Features
Rounded fan shape, smooth margins contrasting with fine radial ribs near the umbo, and a distinct lack of deep, coarse ridges across the entire surface compared to other scallop species.
Collector Value
Low to moderate commercial and collectible value. Frequently found in craft markets and shell shops, though large, pristine, naturally sourced specimens remain popular with beachcombers.
Condition Notes
Good to Fine condition. The shells are intact with well-preserved natural coloration near the umbos and minimal surface wear, showing no major cracks or predator boring holes.
Interesting Facts
Scallops are among the few bivalves that can actively swim by clapping their valves together to expel water, and they possess dozens of tiny, bright blue eyes along the mantle edge that can detect light and shadow.
Ecological Role
Scallops serve as important filter feeders in benthic marine ecosystems, helping to clear the water column of phytoplankton, and act as a vital food source for bottom-dwelling predators such as sea stars, crabs, and fish.
Similar Species
Calico Scallop (Argopecten gibbus), which is smaller and features much more prominent, high-contrast mottled patterns and deep ribs.
Beach Finding Tips
Look along cold-water beaches in the northeast United States and Canada following major storms or heavy winter wave action, particularly near sandy or gravelly offshore bars.