39.7 - 37 Ma

The definition of this interval in the timescale North American Land Mammal Ages is taken from the following source:

• A. D. Barnosky, M. Holmes, R. Kirchholtes, E. Lindsey, K.C. Maguire, A.W. Poust, M.A. Stegner, J. Sunseri, B. Swartz, J. Swift, N.A. Villavicencio and G. Wogan. 2014. Prelude to the Anthropocene: Two new North American Land Mammal Ages (NALMAs). The Anthropocene Review I(3):225-242 view

There are intervals in 9 timescales which overlap this one. show

• International Chronostratigraphic Timescale: Bartonian age, Priabonian age, Eocene epoch
• Cenozoic Subepochs: Middle Eocene subepoch, Late Eocene subepoch
• Mammal Paleogene Zones: MP 16 zone, MP 19 zone, MP 18 zone, MP 17A zone, MP 17B zone, MP 20 zone
• Paleogene Mammal Ages of Asia: Houldjinian age, Ergilian age, Arshantan age, Ulangochuian age, Sharamurunian age, Irdinmanhan age
• South American Land Mammal Ages: Divisaderan age
• Calcareous Nannoplankton Zones: NP17 zone, NP18 zone, NP16 zone
• Planktic Foraminiferal Zones: M. crassatus HOZ zone, G. semiinvoluta HOZ zone
• Geomagnetic Polarity Chrons: C17 chron, C18 chron
• Cretaceous-Cenozoic of New Zealand: Arnold epoch, Bortonian age, Kaiatan age

This interval is used in the definition of 109 collections

A total of 1926 collections with 23788 occurrences lie within this time span