Late Pliocene; Extinct.
Southern Florida to Viriginia.
Original Description (from Conrad, 1839, p. 51):
"Shell very oblique, convex-depressed; ribs about 26, broad, flat; interstices narrow and very shallow; summit narrow and not very prominent, oblique; anterior margin rectilinear, extremity angular; posterior extremity rounded; basal margin very long, arcuated. Length about 4 inches. Locality, James river, near Smithfield."
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