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 have been reported in at least one of these specimens. The abundance of fossil material has allowed significant research into many aspects of its biology, including its life history and biomechanics. The feeding habits, physiology and potential speed of "Tyrannosaurus rex" are a few subjects of debate. Its taxonomy is also controversial, as some scientists consider "Tarbosaurus bataar" from Asia to be a second "Tyrannosaurus" species while others maintain "Tarbosaurus" is a separate genus. Several other genera of North American tyrannosaurids have also been synonymized with "Tyrannosaurus". As the archetypal theropod, "Tyrannosaurus" is one of the best-known dinosaurs since the