45.9 - 39.7 Ma

The definition of this interval in the timescale North American Mammal Subages/Zones is taken from the following source:

• M. O. Woodburne. 1987. A prospectus of the North American Mammal Ages. In: Woodburne, M. O. (ed.), Cenozoic Mammals of North America. University of California Press, Berkelery, CA 285-290 view

There are intervals in 11 timescales which overlap this one. show

• International Chronostratigraphic Timescale: Eocene epoch, Bartonian age, Lutetian age
• Cenozoic Subepochs: Middle Eocene subepoch
• Mammal Paleogene Zones: MP 13 zone, MP 14 zone, MP 16 zone, MP 15 zone, MP 11 zone, MP 12 zone
• Paleogene Mammal Ages of Asia: Irdinmanhan age, Sharamurunian age, Arshantan age
• North American Land Mammal Ages: Uintan age
• North American Mammal Subages/Zones: Early Uintan subage
• South American Land Mammal Ages: Mustersan age, Divisaderan age
• Calcareous Nannoplankton Zones: NP15 zone, NP16 zone
• Planktic Foraminiferal Zones: G. nuttalli LOZ zone, M. lehneri PRZ zone, M. crassatus HOZ zone, A. topilensis PRZ zone, O. beckmanni TRZ zone, G. kugleri/M. aragonensis CRZ zone
• Geomagnetic Polarity Chrons: C19 chron, C20 chron, C18 chron
• Cretaceous-Cenozoic of New Zealand: Heretaungan age, Porangan age, Bortonian age, Arnold epoch, Dannevirke epoch

This interval is used in the definition of 31 collections

A total of 3712 collections with 35913 occurrences lie within this time span