Corbicula fluminea (Müller, 1774)
Other common names Asiatic clam,Corbicula.
Key characters Relatively small, yellowish brown to black shell with numerous, evenly spaced, concentric, elevated ridges on the surface. Three cardinal teeth in each valve located below the umbo. Paired lateral teeth in each valve, two on each side of the umbo in the right valve, one on each side in the left. The presence of serrated lateral teeth separate Corbicula from the fingernail- clams.
Similar species Fingernailclam.
Description Shell rounded to slightly triangular and inflated. Anterior and posterior margins rounded. Umbos high, centrally located, and elevated above the hinge line. Periostracum yellowish brown to black with numerous concentric rows of elevated lines covering the surface of the shell. Young shells with a purple stripe on the umbo. Length to 1.5 inches (3.8 cm).
Three triangular cardinal teeth in each valve located directly below the umbo. Two sets of lateral teeth in each valve, moderately long, straight, and serrated; paired in the right valve, one on each side in the left. Beak cavity deep. Nacre white or purple and highly polished outside of the pallial line.
Habitat Lakes and streams of all sizes in silt, mud, sand, or gravel.
Status Widespread and common. Introduced.