Pachycrocuta was a
genus of prehistoric
hyenas. The largest and most well-researched
species is
Pachycrocuta brevirostris, colloquially known as the giant hyena as it is estimated to have averaged in weight, almost the size of a lioness or tigress, making it the largest known hyena.
Pachycrocuta first appeared during the late
Pliocene about 3 million years ago and went extinct during the middle
Pleistocene, 400,000 years ago.