Dire wolf

The dire wolf ("Canis dirus", "fearsome dog") is an extinct species of wolf in the genus "Canis". It is one of the most famous prehistoric carnivores in North America. The dire wolf lived in the Americas during the Late Pleistocene and Early Holocene epochs (125,000–9,440 years ago). The species was named in 1858, four years after the first specimen had been found. 
Subspecies.
Two subspecies are recognized. These subspecies are "Canis dirus guildayi" and "Canis dirus dirus". The dire wolf probably evolved from Armbruster's wolf ("Canis armbrusteri") in North America. 
The dire wolf was about the same size as the largest gray wolves alive now.
Diet.
The dire wolf probably ate horses, ground sloths, mastodons, bison, and camels. The dire wolf was probably a pack hunter. This means that many dire wolves would hunt for prey together. Modern wolves are also pack hunters.
Extinction.
The dire wolf became extinct during the Quaternary extinction event.