Geringian
Introduction The '''Geringian North American Stage''' on the geologic timescale is the North American  faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 30,800,000 to 26,300,000 years BP, a period of  . It is usually considered to fall within the Oligocene epoch. The Geringian is preceded by the Whitneyan and followed by the Monroecreekian NALMA stages.The Geringian overlaps with the Rupelian and Chattian ages.
References