24.7 - 23.1 Ma

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

• J. Alroy. 2000. New methods for quantifying macroevolutionary patterns and processes. Paleobiology 26(4):707-733 view

The top and bottom ages have been interpolated based on the differences between the ages for international timescale boundaries quoted in the source and the currently accepted ages for those boundaries.

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

• International Chronostratigraphic Timescale: Chattian age, Oligocene epoch
• Cenozoic Subepochs: Late Oligocene subepoch
• Mammal Paleogene Zones: MP 27 zone, MP 25 zone, MP 29 zone, MP 26 zone, MP 28 zone, MP 30 zone
• Paleogene Mammal Ages of Asia: Tabenbulakian age, Hsandagolian age
• North American Land Mammal Ages: Arikareean age
• North American Mammal Subages/Zones: late Late Arikareean subage, early Early Arikareean subage, early Late Arikareean subage, late Early Arikareean subage
• South American Land Mammal Ages: Deseadan age
• Calcareous Nannoplankton Zones: NP25 zone, NN1 zone
• Cretaceous-Cenozoic of New Zealand: Landon epoch, Waitakian age

This interval is used in the definition of 51 collections

A total of 36 collections with 210 occurrences lie within this time span