Angulomastacator (meaning "bend chewer", in reference to both the shape of its upper jaw and to the Big Bend area of the Rio Grande, where the type specimen was found) is a genus of duck-billed dinosaur from the Campanian-age (Late Cretaceous) Aguja Formation of Big Bend National Park, Texas.
In 2009, Purnell conducted a study into the chewing methods and diet of hadrosaurids, a herbivore species of duck-billed dinosaurs from the Late Cretaceous period.
Animals named by Langston include the theropod Acrocanthosaurus (1950), the hadrosaurid dinosaur Lophorhothon (1960), and the microsaur Carrolla (1986).