Late Pliocene to Late Pleistocene; Extinct.
Southern Florida to North Carolina.
Original Description (from Dall, 1903, p. 1290):
"Miocene of Florida, sixteen miles southwest of Tallahassee near and at Jackson Bluff (upper bed); Vaughan.
Shell rather large, compressed, the sculpture behind the middle of the disk obsolete, the radial feebly defined, the concentric lamellae little elevated and distant; hinge normal, the teeth entire; anterior adductor scar elongated, posterior shorter and smaller; pallial sinus nearly obsolete; lunule slightly larger and proportionately narrower than in C. cancellata. Length 35, height 32, diameter 17 mm.
Many of the specimens have the sculpture almost entirely obsolete."
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