Irvingtonian


The Irvingtonian North American Land Mammal Age on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology, spanning from 1.9 million – 250,000 years BP. Named after an assemblage of fossils from the Irvington District of Fremont, California, the Irvingtonian is usually considered to overlap the Lower Pleistocene and Middle Pleistocene epochs. The Irvingtonian is preceded by the Blancan and followed by the Rancholabrean NALMA stages.
The Irvingtonian can be further divided into substages:
The beginning of the Irvingtonian is defined by the first appearance of Mammuthus south of 55° N in North America, and the beginning of the succeeding Rancholabrean is defined by the first appearance of Bison.

Fauna

Notable mammals

Artiodactyla - even-toed ungulates
  • Platygonus, peccaries
Carnivora - carnivores
Lagomorpha - lagomorphs
Perissodactyla - odd-toed ungulates
  • Nannippus, horses
  • Plesippus, horses - may belong in Equus
Proboscidea - elephants
  • Elephantidae, mammoths
  • Mammutidae, mastodons
  • Rhynchotherium, gomphotheres
  • Stegomastodon, gomphotheres
Rodentia - rodents
  • Paenemarmota, giant marmots

    Notable birds

Charadriiformes
Falconiformes - diurnal raptors
Passeriformes