Pegomastax

Pegomastax Temporal range: Early Jurassic, 200–190 Ma PreЄ Є O S D C P T J K Pg N
Lower jaws of specimen SAM-PK-K10488
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Clade:	Dinosauria
Order:	†Ornithischia
Family:	†Heterodontosauridae
Subfamily:	†Heterodontosaurinae
Genus:	†Pegomastax Sereno, 2012
Type species
†Pegomastax africana Sereno, 2012

Pegomastax ("strong jaw") is a genus of heterodontosaurid dinosaur discovered in Lower Jurassic rocks in South Africa. It is based on SAM-PK-K10488, a partial skull including a postorbital bone, both dentaries (the tooth-bearing bone of the lower jaw), and a predentary (a toothless beak-like bone found at the tip of the lower jaw). From head to tail the parrot-like herbivore measured no more than 60 cm.

This specimen was found in Voyizane, Joe Gqabi District, Cape Province, in rocks of the upper Elliot Formation, a rock formation that dates to the early part of the Early Jurassic (Hettangian–Sinemurian, approximately 200 to 190 million years ago). It was collected during a 1966–1967 expedition but not formally named and described until 2012, when Paul Sereno, who had recognized it as unusual in the 1980s, published a description. The type species is P. africana.Pegomastax differed from other heterodontosaurids by details of the skull. The lower jaw was robust, with a short beak. Like most other heterodontosaurids, Pegomastax had an enlarged canine-like tooth at the beginning of the lower jaw's tooth row, which may have had a defensive function.