Original: The Marsupial Lion (Thylacoleo carnifex, the "murderous (or 'meat-cutting') marsupial lion" from thylakos - pouch, leo - lion, carnifex - murderer, tormentor, 'butcher') is an extinct species of carnivorous marsupial mammal that lived in Australia from the early to the late Pleistocene (1,600,000–46,000 years ago).
Simplified: The Marsupial Lion, Thylacoleo carnifex, is an extinct species of carnivorous marsupial  that lived in Australia from the early to the late Pleistocene, from 1,600,000 to 40,000 years ago. The scientific name comes from the words thylakos - pouch, leo - lion, and carnifex - murderer, tormentor, or butcher.