Wikipedia
Changhsingian
In the geologic time scale, the Changhsingian or Changxingian is the latest age or uppermost stage of the Permian. It is also the upper or latest of two subdivisions of the Lopingian epoch or series. The Changhsingian lasted from to million years ago (Ma). It was preceded by the Wuchiapingian and followed by the Induan.
The greatest mass extinction event in the Phanerozoic eon occurred during this age. The extinction rate peaked about a million years before the end of this stage.