The extinct North American wolf that lived during the Pleistocene and was generally more massive than modern gray wolves was the dire wolf.
The dire wolf, traditionally known as Canis dirus and now often classified as Aenocyon dirus, was a distinctive Ice Age predator of North America. It lived alongside mammoths, ancient bison, horses, camels, ground sloths, and other megafauna, with fossils found at famous sites such as California's La Brea Tar Pits.
Dire wolves had heavy skulls, powerful jaws, and large shearing teeth suited to processing large prey and cracking bones. Average weight estimates vary by population, but some forms averaged roughly 60 to 68 kilograms, making them heavier and more robust than many modern gray wolves. They were not simply oversized gray wolves: genetic evidence shows that dire wolves belonged to a separate evolutionary lineage.
The species survived until the end of the Pleistocene, roughly 10,000 years ago. Its disappearance occurred during a period of major climate change and megafaunal losses, when prey communities and ecosystems were being transformed across North America. Despite its name, the dire wolf was a real prehistoric animal, not merely a legendary wolf.