Tivela
Look alikes:
The genera Tivela and Planitivela share the characteristic split posterior tooth (3b) on the right valve. Species of the genus Tivela have more inflated valves and more prominent umbones than those of Planitivela (Olsson 1961).
Morphology:
Within the species of the genus Tivela, the posterior tooth (3b) on the right valve is extremely bifid, resulting in the appearance of four cardinal teeth, rather than three.