Early Miocene; Extinct.
Original Description (from Dall, 1903, p. 1432-1433):
"Oligocene of the Chipola beds on the Chipola River and Alum Bluff on the Chattahoochee River; Dall and Burns.
Shell small, solid, rounded or ovate, slightly inequilateral, with a lanceolate escutcheon and a subcordate, smooth, impressed lunule; sculpture of twelve or thirteen narrow, squarish, closely nodulous radial ribs separated by wider interspaces, faintly concentrically striated; beaks rather low, slightly prosogyrate, situated at the anterior third; hinge heavy, the laterals distinct; internal margins strongly fluted. Length 4.0, height 3.5, diameter 2.75 mm.
Exceptional specimens may reach a length of five millimetres, and some specimens are shorter and higher than others."
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