 However, Quebrada del Barro is more abundant in sphenodontians ("Sphenotitan"), tritheledontid cynodonts, and coelophysoid dinosaurs ("Lucianovenator"), while sauropodomorphs are somewhat less common and aetosaurs are completely absent, in contrast to the Los Colorados Formation.Sphenodontians and cynodonts are also abundant in microfossil assemblages.In addition, the Quebrada del Barro Formation preserves some of the only pterosaur and "Dromomeron" specimens known from Triassic strata in Argentina.