Wikipedia
Charassognathus (meaning 'notched jaw') is an extinct genus of Late Permian cynodont. Described in 2007 from a locality near Fraserburg, South Africa, Charassognathus is the earliest and most basal cynodont. It is known only from the Holotype which dates from the upper Permian Period. The type species C. gracilis is the only species of Charassognathus. The holotype ( South African Museum SAM-PK-K 10369) is made up of a crushed skull, partial lower jaw and one leg.
Charassognathus was a quadrupedal predator. It was named for a notch on its coronoid process which most likely was the insertion point for a chewing muscle, the adductor mandibulae externus. Charassognathus was a tiny animal, with a skull only 5 centimeters in length. Since the body of Charassognathus hasn't been discovered, its full length remains unknown, but estimates have been made at 50 centimeters.