Early Miocene; Extinct.
Original Description (from Dall, 1892, p. 374):
"Old Miocene of the Chipola beds, near Bailey's Ferry, Chipola River, Calhoun Co., Florida.
Shell closely related to Ampullina sigaretina of the Parisian Eocene, from which it differs by its somewhat more depressed spire, less impressed suture, wider basal fasciole, and by the thick, complete coat of callus, which in the adult covers completely the fasciole and umbilicus, as in Cernina fluctuosa. The shell is also slightly less expanded and rounded than the European fossil. It has a low but pointed spire, six or seven whorls, smooth surface with impressed incremental lines, slightly flattened callus, and in front of the suture the whorl is flattish instead of rounded, as in A. sigaretina. A shell of six whorls measures 33 mm. high and 38 mm. in maximum diameter, but I have fragments which measure over 60 mm. in diameter.
This form was at first regarded by me as being merely a mutation of A. streptostoma, but of more than twenty-five specimens from various localities which were in a state to show the base, not a single one has an open umbilicus, while all the Ballast Point and Claibornian specimens have the umbilicus open. The young of both are not separable. It may eventually prove to be a local race of A. streptostoma, but at present would seem better kept apart.
It is respectfully dedicated to Dr. Paul Fischer, of Paris, the distinguished paleontologist and malacologist."
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