The phylogenetic position of the Tyrannosauridae: implications for theropod systematics | Semantic Scholar

A new cladistic analysis of the early dinosaur radiation was performed to assess the relationships among the three major clades (Ornithischia, Sauropodomorpha and Theropoda) and to define the phylogenetic position of the basal members of the group.

An analysis of forty one primary ingroup taxa and 386 characters yielded a set of most parsimonious cladograms which preserves many previously discovered relationships, and a mosaic of derived character state distributions for troodontids relative to the dromaeosaurid-bird-bird clade, the tyrannosaurids-ornithomimosaur clades, and the therizinosauroid-oviraptorosaur clade suggests that relationships alternative to the most Parsimonious

A new giant carnivorous dinosaur from the Upper Creta-ceous of northwestern Patagonia (Argentina) is reported, characterized by a proportionally low skull, a reduced shoulder girdle, and robust vertebrae and hind limbs, and provides an opportunity to exam-ine the Gondwanan dinosaur palaeocommunities and their relation to those from Laurasia.