Reconsideration of Dating of the Late Paleozoic Radiolarian Latentifistula crux Ecozone in the Southern Urals

Resumo

The age of the Upper Paleozoic radiolarian Latentifistula crux Ecozone is revised. The Latentifistula crux assemblage was originally established by Nazarov and Ormiston (1985, 1990, 1993; Nazarov, 1988) in 1985 in the basal deposits of the Asselian Stage of the Nikolskoe section on the Ural River. The new biostratigraphic position of the radiolarian Latentifistula crux Ecozone corresponds to the terminal Streptognathodus bellus and Streptognathodus wabaunsensis conodont zones of the Gzhelian Stage (Chernykh, 2012, 2016).