Abstract:
Seventeen taxa of Pectinidae (Bivalvia) from lower Miocene to lower Pleistocene strata in the Lee Creek Mine,
North Carolina, and surrounding region were studied biometrically. The study of large population samples clarifies
the relationships of the taxa and their biostratigraphic utility. Because of widespread geographic distribution of the
species into various environmental conditions and relatively
short time ranges, the pectens make ideal index species for
the outcropping strata. The co-existence of planktonic Foraminifera with the pectinids in some of the strata allows
correlation with European stages.
Characters found to be most important for discrimination
at the subspecific and specific levels include the byssai notch,
shape of the resilial insertion, size and shape of the auricles,
number and shape of the plicae, and convexity of the valves.
One new species, Pecten mclellani, is described from the
upper lower Miocene part of the Pungo River Formation
exposed at the Lee Creek Mine. It is demonstrated that
Chlamys decemnaria (Conrad) from the Pliocene should include C. virginianus (Conrad). A probable intermediate
form between Placopecten clintonius of early Pliocene age
and the living P. magellanicus is illustrated and described.
Other rearrangements at the subspecific level are made.
Lectotypes are selected for Pecten yorkensis Conrad, 1867,
Pecten eboreus darlingtonensis Dali, 1898, Pecten eboreus urbannaensis Mansfield, 1929, Pecten ( Chlamys) eboreus bertiensis Mansfield, 1937, and Amusium precursor Dali, 1898.
