Biostratigraphic Potential of the Cryptodont Bivalve Buchiola Retrostriata From Upper Devonian Shale, Southwestern Virginia

Abstract

Buchiola retrostriata (von Buch), a former inhabitant of muddy deep-sea substrata, can be used to identify lower Upper Devonian shale (about middle Finger Lakes to basal Cohocton) in Virginia. This distinctive and fairly abundant cryptodont clam has potential as a zonal guide fossil for rocks characterized by what has been traditionally termed the "Naples fauna" in the Appalachian Basin.