Late Pliocene to Middle Pleistocene; Extinct.
Southern Florida to Virginia.
Original Description (from Dall, 1892, p. 386-387):
"Newer Miocene of the Cape Fear River, North Carolina? Johnson; Pliocene of the Caloosahatchie beds, Dall; and the Myakka River and Shell Creek, Willcox.
Shell small, rather elevated, with a smooth, one-whorled, minute nucleus and three subsequent spirally sculptured whorls; whorls shouldered by a more or less evident obtuse keel above, obsolete toward the aperture; early whorls more coarsely, later ones finely evenly spirally grooved above and below; base amply rounded; umbilicus very minute, margined by a stout rounded striated rib; aperture rounded, pillar broad, arched, sulcate at the base opposite the umbilical rib, with a prominent pustule above and a smaller one below the sulcus; outer lip reflected and thickened in the adult, smooth within, joined to the pillar by a thin callus in the adult. Alt. 4.25; max. diam. 4.5 mm.
The specimen from the Cape Fear River may possibly have been derived from adjacent Pliocene beds. Some young specimens show a considerably coarser spiral sculpture than the majority of individuals, but there are intermediate gradations."
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