Raptorex Raptorex Raptorex is a dubious genus of tyrannosaurid dinosaur. Its fossil remains consist of a single juvenile specimen probably uncovered in Mongolia, or possibly northeastern China. The type species is "R. kriegsteini", described in 2009 by Sereno and colleagues. The genus name is derived from Latin ', "robber", and ', "king". The specific name honours Roman Kriegstein, a survivor of the Holocaust, whose son Henry Kriegstein donated the specimen to the University of Chicago for scientific study. While initially considered to have come from the Yixian Formation of China, dated to approximately 125 million years ago during the early Cretaceous
Tyrannosaurus considered "Tyrannosaurus rex" remains. In 1892, Edward Drinker Cope found two vertebral fragments of large dinosaur. Cope believed the fragments belonged to an "agathaumid" (ceratopsid) dinosaur, and named them "Manospondylus gigas", meaning "giant porous vertebra", in reference to the numerous openings for blood vessels he found in the bone. The "M. gigas" remains were, in 1907, identified by Hatcher as those of a theropod rather than a ceratopsid.. Henry Fairfield Osborn recognized the similarity between "Manospondylus gigas" and "Tyrannosaurus rex" as early as 1917, by which time the second vertebra had been lost. Owing to the fragmentary nature of the