Late Pliocene to Late Pleistocene; Recent.
Southern Florida to Virginia.
Original Description (from Conrad, 1837, p. 239-240):
"Shell elliptical, compressed; anterior margin very regularly rounded; posterior side with a slight fold; disk with numerous prominent not very regular concentric striae, and obscure radiating lines, which are profound near the anterior and posterior extremities; beaks rather nearer the posterior extremity; lateral teeth prominent, distinct in both valves; margin entire.
Inhabits Mobile Point, Alabama. Occurs sparingly in the Newer pliocene marl, near Newbern, N. C."
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