Zunityrannus was a mid-sized tyrannosaur that lived [92-87] million years ago in what will one day be the Zuni Basin in New Mexico, USA. Zunityrannus appeared in the Episode "The Great Survivors" when an individual attacks a pair of Nothronychus, but is driven off. It is then seen feeding off a carcass of another Zunityrannus. Later, the Nothronychus are attacked by a pack of Zunityrannus, but they failed to make a kill and later were forced to feed on the carcass of one of their own kind, which is the same one that tried to attack the Nothronychus earlier, having died for an unknown reason.The pack died shortly afterwards and are revealed to have caught a disease called botulism that is caused by bacteria that thrives in rotting flesh. The narrator later explains that because Nothronychus completely changed it's diet it is usually safe from such dangers that its Tyrannosaur cousins are victims of. It is based on a tyrannosaur that was discovered in the Zuni Basin that has yet to be given a scientific name, and was named "Zunityrannus" by the programme.It was about 5 meters (16.5 ft) long.