Harpymimus, meaning “Harpies mimic”, is a genus of dinosaur from the Early Cretaceous Period of what is now Mongolia. Only one species is known: H. oklandnikovi. It was found in the Shinekhudug Formation at Dundgov, Mongolia. Harpymimus possibly migrated from Asia during the Early Cretaceous and ended up in North America sometime before the Late Cretaceous Period.
The skull of Harpymimus was relatively complete, though badly crushed, which obscured some detail of its anatomy. Evidence shows a possible beak that was used for grasping and holding onto prey. It had a long neck, long arms with sharp claws, and long legs. The teeth of the Harpymimus were small and most likely only used, along with the beak, to grab and hold onto prey. Of all known ornithomimosaurs, Harpymimus and Pelecanimimus were the only two dinosaurs to retain teeth. This was a primitive trait among ornithomimosaurs. The skull length was 10 inches.