SDNHM catalog no. 20829. Crassatellid clam fossil. This specimen measures approximately 4.25 inches (11 cm) long.

Crassatella uvasana
Crassatellid clam
Crassatellacea

Time
Eocene

In Our Region
Shells of C. uvasana have been collected from Eocene-age siltstones in San Diego, Del Mar, Encinitas, Carlsbad, and Leucadia in San Diego County.

Description
Crassatella uvasana is an extinct species of large crassatellid clam. Clams are bivalve mollusks; their shells are made up of two valves (shell halves). The shell may be either triangular, trapezoidal, or rounded in shape, and either smooth or covered with concentric markings that radiate from the hinge. Two or three teeth are typically found on the hinge plate, inside the shell.

These crassatellid clams were common in warm, shallow seas where they burrowed into the sandy substrate for shelter.