The now extinct 'American Lion' was a giant predator roaming North and South America as recently as 11,000 years ago. It is thought to have been about twenty-five percent larger than the modern African lion. "American lions likely preyed on deer, North American horses (now extinct), North American camels, North American tapirs, American bison, mammoths, and other large, herbivorous animals."
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 and northwestern South America during the Pleistocene epoch (0.34 mya to 11,000 years ago), existing for approximately 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).@Wikipedia.org