The Natosians are a near extinct race that were known to inhabit the planet of Natos, the only known member of this species is Wyvern.
The Natosians evolved from intellectual beings, known as Quadillions by modern historians. Quadillions almost went extinct after an unknown plague, but some survived, and evolved into Natosians, which could resist the plague. The Natosians were smarter than the Quadillions, having better physical attributes than them. But, during the year 1953, a scientist named Norx created the Norxus, a mechanical being that used to be a cyberman. It was intended to be used to defend the planet, but it turned it's creator into one of them, and went on to kill all of the Natosians. This would lead to the near extinction of the Natosians. Only one has been known to have survived. This was the last time the Natosians would be seen, as no sign of them would come up in U42's history.
The Natosians have the rare ability to resist almost any plague, due to the fatal plague that struck them in the far past. They also have the ability to renew themselves whenever their body is fatally wounded or 'dies'.