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Evidence of large Tyrannosauroid Dinosaurs living on the East Coast of North America shortly before the End Cretaceous Extinction.
https://sciencythoughts.blogspot.com/2019/04/evidence-of-large-tyranosauroid.html
Ben CreislerA new paper not yet mentioned:Chase D. Brownstein (2018)Large basal tyrannosauroids from the Maastrichtian and terrestrial vertebrate diversity in the shadow of the K-Pg extinctionThe Mosasaur 10: 105-115Free pdf:The extinction of the non-avian dinosaurs during the Cretaceous-Paleogene event is one of the most discussed subjects in paleontology. However, the diversity, biogeography, and ecology of this and other clades of terrestrial vertebrates proximal to the extinction are poorly known. The terrestrial record from this period comes almost exclusively from a relatively small region in western North America. This scarcity of fossil evidence has contributed to a fairly poor understanding of the effects of the extinction on ecosystems on land. Here, I describe three foot bones of large tyrannosauroid theropods collected from marine deposits near the coastal margin of the Cretaceous Atlantic Ocean that add to the notoriously poor dinosaur fossil record from eastern North America. Despite their late Maastrichtian age, these bones retain characteristics that indicate a basal position relative to the coeval Tarbosaurus bataar and Tyrannosaurus rex. The new pedal elements represent the largest known tyrannosauroid dinosaurs from eastern North America, suggesting multiple lineages of tyrant dinosaur approaching 9 meters persisted into the latest Cretaceous. Emphasizing that non-avian dinosaurs remained a diverse clade until their demise, the new bones provide a rare glimpse at the anatomical and evolutionary diversity of megapredatory theropods during the eve of the Mesozoic===