analysis that tyrannosauroids were widespread in Laurasia and Gondwana since the Middle Jurassic. They have proposed new subclade names for Tyrannosaurioidea. The first is Pantyrannosauria referring to all non-proceratosaurid members of the group, while Eutyrannosauria for larger tyrannosaur taxa found in the northern hemisphere such as Dryptosaurus, Appalachiosaurus, Bistahieversor, and Tyrannosauridae. Below is their phylogeographic tree they have recovered, in which displays the phylogenetic relationships of the taxa as well as the continents those taxa have been found. In 2021, Chase Brownstein published a research article based on more thorough descriptions of tyrannosauroid metatarsals and vertebra from the Merchantville Formation in Delaware. This reanalysis of phylogenetic relationships of tyrannosauroids in Appalachia has brought the rediscovery of the clade Dryptosauridae due to the similarities of the metatarsals II and IV compared to the same bones in Dryptosaurus holotype. However the Merchantville taxon was able to still be different enough to separate it on the genus level from Dryptosaurus. In the phylogentic tree constructed Dryptosauridae is found to be a valid family of non tyrannosaurid eutyrannosaur. It currently sits in a potylomy with the Iren Dabasu taxon and more basal eutryannosaurs. Distribution The tyrannosauroids lived on the supercontinent Laurasia, which split from Gondwana in the Middle Jurassic. The earliest recognized tyrannosauroids lived in the Middle Jurassic, represented by the proceratosaurids Kileskus from the Western Siberia and Proceratosaurus from Great Britain. Upper Jurassic tyrannosauroids include Guanlong from China, Stokesosaurus from the western United States and Aviatyrannis and Juratyrant from Europe. Early Cretaceous tyrannosauroids are known from Laurasia, being represented by Eotyrannus from England and Dilong, Sinotyrannus, and Yutyrannus from northeastern China. Early Cretaceous tyrannosauroid premaxillary teeth are known from the Cedar Mountain Formation in Utah and the Tetori Group of Japan. The Middle Cretaceous record of Tyrannosauroidea is rather patchy. Teeth and indeterminate postcrania of this interval are known from the Cenomanian-age Dakota Formation of western North America and Potomac Formation of New Jersey, as well as formations in Kazakhstan and Tajikistan; two genera, Timurlengia and Xiongguanlong, have been found in Asia, while the Brazilian Santanaraptor may belong to this group. Suskityrannus has been found in the Moreno Hill Formation of the Zuni Basin of western New Mexico. The first unquestionable remains of tyrannosaurids occur in the Campanian stage of the Late Cretaceous in North America and Asia. Two subfamilies are recognized. The albertosaurines are only known from North America, while the tyrannosaurines