Incisivosaurus gauthieri -
Literally called the “incisor lizard”, this herbivorous, possibly omnivorous theropod lived during the early Cretaceous in modern day China. It is related to the oviraptors, although its skull and beak were much more distinctive than its later cousins. It is speculated to be the same species as Protarchaeopteryx, but possibly at a different life stage.
The two front incisors were an unusual trait. Most raptors did not have any teeth. Not only did it have two large incisors, but it also had plant grinding molars and small canines. Its incisors had wear that showed it gnawed on its food, probably feeding on tough seeds and vegetation. It also swallowed stones to help with digestion.
Incisivosaurus was a small raptor which grew to about 3 feet long and only weighed about 10 lbs. Like most other theropods and oviraptors, it was feathered and shared similar skeletal traits to the birds of today.