Late Pliocene to Middle Pleistocene; Extinct.
Southern Florida to Virginia.
Original Description (from Dall, 1898, p. 767):
"Oligocene of the Oak Grove sands, Santa Rosa County, Florida, Burns; Miocene of Darlington, South Carolina, and the Duplin Natural Well, Duplin County, North Carolina, Burns.
Shell small, thin, inflated, oblique, with a moderate gape, sculptured with concentric lines of growth and rather sharp, fine, numerous, somewhat irregular radial threads, obsolete on the beaks, absent from the posterior submargin and the anterior ears; submargins not impressed, beak prominent, ears small, the margin of the gape forming a concave sinuosity in front of and below the anterior beak; hinge-line short, with a very wide pit, its lower margin projecting from the cardinal plate; interior radially striate, the basal margin slightly crenulate. Alt. 16, lat. 12, diam. 7 mm.
This differs from L. papyria Conrad, from the Maryland Miocene, in the absence of the angle which in the latter species modifies the margin just below the anterior car, and in the presence of dense radial striation on the anterior submargin, while in L. papyria this region is smooth."
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