Proceratosauridae is a family or clade of tyrannosauroid theropod dinosaurs from the Middle Jurassic to the Early Cretaceous.
They defined the clade containing these two dinosaurs as all theropods closer to Proceratosaurus than to Tyrannosaurus, Allosaurus, Compsognathus, Coelurus, Ornithomimus, or Deinonychus.
[4] Recently, Proceratosauridae has been found to include Proceratosaurus, Guanlong, Kileskus, Sinotyrannus, and the genera Stokesosaurus, Juratyrant, and Dilong previously recognized as non-proceratosaurid tyrannosauroids.
[2][5] In their re-evaluation of Proceratosaurus, Rauhut et al. stated that tooth taxa from the Late Jurassic and Early Cretaceous previously assigned to the dromaeosaurid subfamily Velociraptorinae may instead be proceratosaurid in nature, due to the similarity between the teeth of the two groups and the fact that velociraptorines are otherwise unknown from the fossil record until the Late Cretaceous.
[2] Proceratosaurus Kileskus Guanlong Sinotyrannus Juratyrant Stokesosaurus An analysis by Brusatte et al. in 2016 provides both parsimony and Bayesian phylogenetic analyses, with Yutyrannus being placed within Proceratosauridae as a sister taxon to Sinotyrannus and Juratyrant and Stokesosaurus being placed as more advanced tyrannosauroids in each instance.