In 1981, during the Soviet-Mongolian paleontological expedition to the Gobi Desert , a theropod skeleton was discovered. In 1984, the found specimen was named and described by the Mongolian paleontologists Rinchengyin Barsbold and Altangaralyn Perle as a new species of Harpymimus okladnikovi . The generic name contains a reference to harpies - monsters from ancient Greek mythology, with the addition of lat. mimus - "imitator." The species name was given in honor of the Soviet paleontologist Alexei Pavlovich Okladnikov [3] .
The IGM 100/29 holotype sample consists of an almost complete, articulated but crushed skeleton, in which there are no fragments of the shoulder girdle, pelvic girdle and hind limbs. The sample was found in the Shinehuduk Formation ( Dundgov Province), which dates from the middle to late Cretaceous album [3] .
The first harpimim was described in detail in the dissertation of Yoshitsugu Kobayashi in 2004 [4] . In 2005, Barsbold and Kobayashi were diagnosed with harpimima based on a number of anatomical characteristics: 11 teeth in the front of the lower jaw ; the transition between the anterior and posterior caudal vertebrae occurs on the 18th vertebra; triangular depression over the dorsal surface of the deltapectoral crest on the scapula , over the shoulder joint; a low ridge above a characteristic recess along the posterior edge of the scapula; a small but deep collateral cavity on the lateral condyle of the III metacarpal bone [5] .
The skull of a typical specimen of harpimime is almost complete, but is strongly destroyed, which makes some details unclear. There is evidence of a beak covering the upper jaw, which, in combination with the cheek teeth, was most likely used to grab and hold food. Outwardly, the animal was similar to late ornithomimosaurs: a long neck, long tenacious paws and long legs with legs. Harpimim's teeth differ from the teeth of another basal ornithomimosaurus - pelecanimimus - in that they are limited by the location on the tooth bone, cylindrical in shape and separated by interdental plates, with at least 10 or 11 teeth on each side. The pelicanimus dental apparatus consisted of 75 teeth on each side of the lower jaw and 35 teeth on each side in the upper. Harpimimus probably used his small teeth only for capturing and holding food, while other theropods could chop and tear the flesh of the victims with their teeth. Of all known ornithomimosaurs, only harpimim and pelecanimimus have preserved teeth, which is a primitive (plesiamorphic) sign for the Ornithomimosauria clade. Other basal features are a very short first metacarpal bone and a third metatarsal bone, which, being clamped from above, still does not stand out from the front surface of the metatarsus, so the foot is not arctomatatarsal [5] .
The length of the skull of harpimim is approximately 262 millimeters, which is more than twice its height and less than half the length of the neck, whose length was approximately 600 millimeters [5] .
In the original description, harpimim was taken to its own family Harpymimidae [3] . In a 2005 article, Barsbold and Kobayashi carried out a detailed cladistic analysis and found that harpimim occupies a basal position in the clade Garudimimus brevipes plus Ornithomimidae, but is more advanced than Pelecanimimus polyodon . According to the researchers, the findings of the analysis confirmed the model according to which ornithomimosaurs originated either in East Asia or in Europe before the Barremian era of the Early Cretaceous (130-125 million years ago), and then migrated to North America during or slightly earlier than the Late Cretaceous [5 ] .
