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
Specimens of Tyrannosaurus both humeri and right hand phalanges, as well as metacarpal III. Because the skeleton is of the gracile morphotype, Peck's Rex is believed to be a male, although the hypothesis which suggests that the sex of "Tyrannosaurus" specimens can be determined by the degree of skeletal sturdiness has been debated in recent years. Peck's Rex has been the subject of research regarding parasitic infections in dinosaurs. The forelimbs of Peck's Rex have also been studied as they show evidence of use. This evidence includes the construction of metacarpal III, as well as repeated fractures in the furcula – possibly caused