Early Miocene to Middle Miocene; Extinct.
Original Description (from Dall, 1898, p. 678):
"Middle Oligocene of the Chipola beds at Alum Bluff and on the Chipola River, Florida, and in the silex beds at Ballast Point, Tampa Bay, Florida; Dall and Burns.
Shell rather thin, irregular, coarsely ribbed, more or less imbricated, margin plicate, form tending to ovate or rounded."
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