First Report of Peripheral Nerves in Post-Cranial Elements of Cacops Williston, 1910, (Temnospondyli: Dissorophidae) from the Lower Permian Richards Spur, Oklahoma

Abstract: Permian bone beds that extend across several states in the US have been known for over 200 years. Those beds have yielded the richest assemblage of the world’s oldest amphibian tetrapod bones in the world. Cacops sp., a well-known amphibian tetrapod from these deposits, has been widely studied, however, no bone histology or bone decalcification has been conducted on these important animals. We report here on the results of decalcification of post-cranial limb elements of Cacops sp., donated by the Sam Nobel Oklahoma Museum of Natural History. Our results include the presence of nerve fibers that display the diagnostic crosshatch pattern known to enclose nerve fascicles and axons, and lipid droplets that exude under cover slip pressure.

Keywords: Permian, amphibian tetrapods, peripheral nerves, nerve fibers, lipids