The Late Triassic is the third and final epoch of the Triassic Period in the geologic timescale. The Triassic-Jurassic extinction event began during this epoch and is one of the five major mass extinction events of the Earth. The corresponding series is known as the Upper Triassic. In Europe the epoch was called the Keuper, after a German lithostratigraphic group (a sequence of rock strata) that has a roughly corresponding age. The Late Triassic spans the time between 237 Ma and 201.3 Ma (million years ago). It is preceded by the Middle Triassic epoch and is followed by the Early Jurassic epoch. The Late Triassic is divided into the Carnian, Norian and Rhaetian ages.