Smooth Duck Clam or Lateral Duck Clam
Phylum: Mollusca, Class: Bivalvia, Order: Cardiida, Family: Cardiidae, Genus: Anatina, Species: Anatina anatina · Cardiidae (Cockle family) · Bivalve (clam/two-shelled), whole shell, ovate to triangular fan shape
Species
Anatina anatina
Shell Type
Bivalve (clam/two-shelled), whole shell, ovate to triangular fan shape
Family
Cardiidae (Cockle family)
Size
Approximately 1 to 1.5 inches in length, which is average for this species. Adults typically range from 1 to 2 inches.
Color & Pattern
Pale whitish base color with concentric growth rings and a warm, brownish-orange patch near the umbo (beak). The colors are natural and well-preserved.
Rarity
Common, frequently discovered during routine beachcombing after heavy tides or storms.
Habitat
Found in shallow marine waters, typically buried just beneath the surface in sandy or muddy substrates of intertidal zones and shallow bays.
Geographic Range
Widely distributed across coastal regions of the Indo-Pacific and parts of the Eastern Atlantic.
Description
An attractive, compact bivalve shell featuring a smooth, rounded outline with fine concentric growth lines. The umbo is prominent, showing a distinct gradient from white to a warm peach-brown. The margins are smooth and the interior exhibits a clean, porcelain-like finish.
Key Features
Compact rounded-oval shape, prominent smooth concentric ridges, and a characteristic warm-toned umbo area distinguishing it from other small bivalves.
Collector Value
Low to moderate commercial value, commonly collected by amateur beachcombers rather than specialized conchologists, with individual values typically nominal.
Condition Notes
Good condition, whole single valve with intact margins and clear color patterns, minor natural wear near the edges; collectibility grade is Good.
Interesting Facts
Like many bivalves, this species uses a muscular foot to burrow into the sand to escape predators and maintain stability in shifting coastal tides.
Ecological Role
Serves as an important prey item for shorebirds, crabs, and carnivorous gastropods, contributing to the benthic food web of sandy coastal ecosystems.
Similar Species
Various small venus clams and cockle species, which can be distinguished by heavier radial ribs or distinct hinge teeth.
Beach Finding Tips
Look along sandy beaches during low tide, particularly in the wrack line where shells wash ashore following windy weather or high surf.