Early Miocene; Extinct.
Original Description (from Dall, 1903, p. 1290):
"Oligocene of the Chipola horizon at Alum Bluff and on the Chipola River, Calhoun County, Florida; Dall and Burns.
Shell moderately convex, in general much resembling C. cancellata, but smaller, with the radial sculpture finer, the radii more numerous, the concentric lamellae more regularly, evenly, and distinctly fluted on the ventral side, the lunule larger, and the pallial sinus more sharply angular. The mutations of the individuals pass through about the same range as in C. cancellata, but modified by the differences above noted. Length of a fully adult specimen 32.0, height 25.5, diameter 18.0 mm."
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