Panthera youngi is known from Choukoutien, northeastern China and Japan, and lived about 350,000 years ago in the Pleistocene epoch, Harington, 1969 suggested that the American lion, the Eurasian cave lion and the large Chinese "Panthera youngi" are conspecific, The American lion ("Panthera leo atrox" or "P. atrox" ) – also known as the North American lion, Naegele’s giant jaguar or American cave lion – is an extinct lion of the family Felidae, endemic to which location during the Pleistocene epoch?
American lion The American lion ("Panthera leo atrox" or "P. atrox" ) – also known as the North American lion, Naegele’s giant jaguar or American cave lion – is an extinct lion of the family Felidae, endemic to North America during the Pleistocene epoch (340,000 to 11,000 years ago), existing for about 0.33 million years. It has been shown by genetic analysis to be a sister lineage to the Eurasian cave lion ("Panthera leo spelaea" or "P. spelaea"). It was part of the abundant Pleistocene megafauna, a wide variety of very large mammals that lived at the time. The most abundant remains have come from the La Brea Tar Pits.
Neoplagiaulax Neoplagiaulax is a mammal genus from the Paleocene of Europe and North America. In the case of the latter continent, there may possibly be some slightly earlier, Upper Cretaceous material too. It existed in the age immediately following the extinction of the last dinosaurs. This animal was a member of the extinct order Multituberculata, lying within the suborder Cimolodonta and family Neoplagiaulacidae.