Early Miocene to Middle Miocene; Extinct.
Original Description (from Dall, 1903, p. 1354):
"Upper Oligocene of the Oak Grove sands, at Oak Grove, Santa Rosa County, Florida; Burns.
Shell much resembling L. janus, but with the beaks slightly more anterior, the posterior dorsal area distinct, the anterior more emphatic, the concentric striation stronger, the lunule shorter and wider, and the surface retaining traces of four or five color zones alternately lighter and darker. The scar of the posterior adductor is also rather longer. Height 36, length 41, diameter 25 mm. A large fragment is 65 mm. long, and the interior, except in the middle of the disk, is rather conspicuously radially striate. The best preserved specimens show a fine, even, concentric lamellation on the dorsal areas."
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