Gondwanax (meaning "lord of Gondwana") is an extinct genus of silesaurid dinosauriform from the Triassic Pinheiros-Chiniquá Sequence of Brazil.

While the possession of two sacral vertebrae characterizes more basal "silesaurid" taxa, Gondwanax has three—the oldest occurrence of this trait in the fossil record.

[1] In 2024, Rodrigo Temp Müller described Gondwanax paraisensis as a new genus and species of silesaurids based on these fossil remains.

[3][4] These results are displayed in the cladogram below:[1] Saurischia Soumyasaurus Asilisaurus Gamatavus Gondwanax Amanasaurus Technosaurus Ignotosaurus Sacisaurus Lutungutali Eucoelophysis Pisanosaurus Laquintasaura Gondwanax was found in the "Linha Várzea 2" site of the Dinodontosaurus Assemblage Zone (AZ) of the Santa Maria Formation.

[9][10] The Brazilian Dinodontosaurus Assemblage Zone shares many faunal similarities with the Argentinian Tarjadia Assemblage Zone, the dinosauromorph-bearing units of the Tanzanian Lifua Member, and the Zambian Ntawere Formation, potentially indicating that these units belong to similar temporal ranges.