Open Paleo

Pegomastax

Sereno, 2012 peg-o-mas-tahks

From Greek pego- (πηγός, 'strong' or 'stout') and mastax (μάσταξ, 'jaw' or 'mouth'), meaning 'strong jaw', referring to its robust lower jaw

201.4–192.9 million years ago Hettangian–Sinemurian, Early Jurassic
Early Jurassic stages

Pegomastax is a genus of heterodontosaurid dinosaur that lived during the Early Jurassic of South Africa. The only known specimen was discovered in a 1966-1967 expedition in Transkei District of Cape Province, but was not described until 2012 when Paul Sereno named it as the new taxon Pegomastax africana. The genus name is derived from the Greek for "strong jaw", and the species name describes the provenance of Africa; it was originally spelled africanus, was corrected to africana to align with the gender of the genus name.

Diagnosis

  1. Proportionately deep predentary with dorsal margin about 70% the anteroventral margin
  2. Predentary dorsal margin angled anteroventrally at approximately 45°
  3. Postcaniniform dentary crowns with mesially-bowed primary ridge angling from apical denticle to mesial crown base
  4. Slightly concave denticulate crown margins flanking prominent apical denticle

Species

Pegomastax africana Sereno, 2012

Type species

From Latin 'africana' meaning 'pertaining to Africa', after South Africa, the country where the holotype was discovered.

Holotype
SAM-PK-K10488 , Iziko South African Museum
Material
Fragmentary skull preserving right and left dentaries and the predentary
Horizon
upper Elliot Formation, Hettangian–Sinemurian, Early Jurassic , 201.4–192.9 million years ago
Locality
Voyizane, Eastern Cape, South Africa

References

  1. Kitching, J. W.; Raath, M. A. (1984). Fossils from the Elliot and Clarens formations (Karoo Sequence) of the northeastern Cape, Orange Free State and Lesotho, and a suggested biozonation based on tetrapods. Palaeontologia africana 25: 111-125.

    Lists "Voisana" (Voyizane, Foisani) at 30°34'S 27°26'E, the table Sereno (2012) cites for the type locality.

    kitching1984a
  2. Sereno, P. C. (2012). Taxonomy, morphology, masticatory function and phylogeny of heterodontosaurid dinosaurs. ZooKeys 226: 1-225. Pensoft Publishers. doi:10.3897/zookeys.226.2840 sereno2012a
  3. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Ornithischians. Princeton University Press.

    Source of the body length, mass, and hip height estimates, and the appearance features.

    jones2026a