SYSTEMATIC REVISIONS TO AOROCRINUS, DORYCRINUS, MACROCRINUS, PARADICHOCRINUS, STROTOCRINUS, AND UPEROCRINUS - MISSISSIPPIAN CAMERATE CRINOIDS (ECHINODERMATA) FROM THE STRATOTYPE REGION

Systematic revisions and revised stratigraphic occurrences are made to Aorocrinus, Dorycrinus, Macrocrinus, Paradichocrinus, Strotocrinus, and Uperocrinus from the Osagean and Meramecian stratotype region in Iowa and Missouri. Systematic revisions include the assignment of Batocrinus procerus Miller and Gurley as a junior synonym of Macrocrinus mundulus. Batocrinus heteroclitus Miller and Gurley, B. vicinus Miller and Gurley, and B. stelliformis Miller and Gurley are assigned to Uperocrinus heteroclitus n. comb. The concept of Aorocrinus spinosulus (Hall) did not match characteristics of the holotype. Consequently, the appropriate name for this concept is Aorocrinus kelloggi (Worthen) n. comb., and A. spinosulus is assigned to Dorycrinus mississippiensis as a junior synonym. Batocrinus strenuus is assigned to Aorocrinus strenuus n. comb.?; and Strotocrinus glyptus is as the valid name for the only species recognized in this genus. These systematic revisions result in the restriction of Strotocrinus glyptus to the middle Osagean Burlington Limestone, and extension of Aorocrinus, Dorycrinus, Macrocrinus, and Uperocrinus into the Meramecian upper Warsaw Formation.