Thanos (named for the Marvel Comics character) is a genus of carnivorous brachyrostran abelisaurid dinosaur that lived in Brazil during the Santonian stage of the late Cretaceous Period.

[1] In 2018, the type species Thanos simonattoi was named and described by Rafael Delcourt and Fabiano Vidoi Iori in an advance online publication in the journal Historical Biology.

[1] The holotype specimen, MPMA 08–0016/95, was found in the São José do Rio Preto Formation, part of the Bauru Group and dating from the Santonian.

Their resulting cladogram is:[1] Chenanisaurus Pourcieux taxon "Kryptops" Rugops Rajasaurus Indosaurus Majungasaurus Genusaurus Arcovenator La Boucharde Taxon Thanos Viavenator Carnotaurus Aucasaurus Abelisaurus Quilmesaurus Pycnonemosaurus Skorpiovenator Ekrixinatosaurus Ilokelesia Xenotarsosaurus Rahiolisaurus Dahalokely Thanos shared only two synapomorphies with the Brachyrostra.

[1] Thanos shared its environment with an undescribed larger theropod believed to be a megaraptoran of which a vertebra, specimen MPMA 08–0003/94, has been found at Ibirá.