page_title: Byronosaurus
section_title: Discovery and naming
hierarchical_section_title: Byronosaurus / Discovery and naming
caption_attribution_description: English: Illustrations of multiple troodontid teeth crowns. A. Troodon formosus, ANSP 9259 (holotype), isolated crown. B. Troodontidae, TMP 83.12.11, isolated crown. C. Zanabazar junior, GIN 100/1 (holotype), premaxillary crown. D. Zanabazar junior, GIN 100/1 (holotype), mesial maxillary crown. E. Sinornithoides youngi, IVPP V9812 (holotype), mesial dentary crown. F. Zanabazar junior, GIN 100/1 (holotype), distal dentary crown. G. Zanabazar junior, GIN 100/1 (holotype), distal maxillary crown. H. Sinornithoides youngi, IVPP V9812 (holotype), mesial maxillary crown. I &amp; J. Non-theropodan teeth whose identities will be revealed at a later date. K. Paronychodon lacustris, morphotype B, isolated crown. L. Byronosaurus jaffei, GIN 100/983 (holotype), mesial maxillary crown. M. Troodontidae, TMP 2000.21.11, isolated crown. N. Euronychodon, isolated crown.
context_page_description: Byronosaurus is a genus of troodontid dinosaur from the Late Cretaceous Period of Mongolia.
context_section_description: In 1993, Michael Novacek, a member of an American Museum of Natural History expedition to the Gobi Desert, discovered the skeleton of a small theropod at Ukhaa Tolgod. This was further excavated in 1994 and 1995. The find was illustrated in a publication in 1994. On 15 July 1996, at the Bolor's Hill site, about eight kilometers (five miles) away from the original location, a second specimen was discovered, a skull.
  In 2000, Mark Norell, Peter Makovicky and James Clark named and described the type species Byronosaurus jaffei. The species name as a whole honoured Byron Jaffe, "in recognition of his family's support for the Mongolian Academy of Sciences-American Museum of Natural History Paleontological Expeditions".
  The holotype, IGM 100/983, was found in a layer of the Djadochta Formation dating from the late Campanian. It consists of a partial skeleton with skull. It contains a partial skull with lower jaws, three neck vertebrae, three back vertebrae, a piece of a sacral vertebra, four partial tail vertebrae, ribs, the lower end of a thighbone, the upper ends of a shinbone and calf bone, a second metatarsal and three toe phalanges. The paratype, specimen IGM 100/984, is the skull found in 1996, of which only the snout has been preserved. Both specimens are of adult individuals.
  In 2003, the skeleton was described in detail.
  In 2009, two front skulls and lower jaws of very young, perhaps newly hatched, individuals, specimens IGM 100/972 and IGM 100/974, were referred to Byronosaurus, after originally having been identified as Velociraptor exemplars.
caption: Comparison of troodontid teeth; L is Byronosaurus
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