Unaysaurus unaysaurid. "Unaysaurus" lived between about 225 to 200 million years ago, in the Carnian or Norian age of the late Triassic period. It was found in the south of Brazil, which at the time was connected to northwest Africa. The whole world was united into the great supercontinent of Pangaea, which was just starting to divide into Laurasia in the north, and Gondwana in the south. A U-Pb (Uranium decay) dating found that the Caturrita Formation dated around 225.42 million years ago, putting it less than 10 million years younger than the Santa Maria and Ischigualasto Formations, from where the
Pangaea Gondwana drifted slowly towards the South Pole. This was the first step of the formation of Pangaea. The second step in the formation of Pangaea was the collision of Gondwana with Euramerica. By the Silurian, 440 Ma, Baltica had already collided with Laurentia, forming Euramerica. Avalonia had not yet collided with Laurentia, but as Avalonia inched towards Laurentia, the seaway between them, a remnant of the Iapetus Ocean, was slowly shrinking. Meanwhile, southern Europe broke off from Gondwana and began to move towards Euramerica across the newly formed Rheic Ocean. It collided with southern Baltica in the Devonian, though this