Early Miocene; Extinct.
Original Description (from Dall, 1892, p. 410-411):
"Older Miocene of the Chipola beds, Calhoun Co., Florida, Burns.
Shell small, with four whorls, the whorls tricarinate, the umbilicus wide, rapidly narrowing, funicular, the outer margin bordered by a crenate rib; suture distinct; transverse sculpture of fine, elevated, close-set lines, which are usually a little gathered up, close to the suture, into short wrinkles; aperture nearly circular, slightly thickened, the outer margin angulate from the ends of the keels. Alt. 2.0; max. diam. 2.5 mm.
This little shell is the precursor of L. gemma of the Newer Miocene and the variety tricarinata Stearns of the Pliocene and recent faunas. From them it differs in its much smaller size and relatively much wider umbilicus. It seems to be very rare in the marl."
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