Y'all may not know much about Appalachiosaurus but it is a very cool species of tyrannosaur. It was likely the apex predator of its namesake home continent of Appalachia, which was separated from Laramidia during the Late Cretaceous as a result of the Western Interior Seaway. While Laramidia does house more famous American dinosaur genera such as Tyrannosaurus, Triceratops, Ankylosaurus, and many others, Appalachian lifeforms aren't as well known, and were in fact completely absent from the fossil record from the Middle Jurassic up until the Early Cretaceous strangely enough.
Now Appalachiosaurus lived alongside a lot of unique basal dinosaurs in its home continent, such as nodosaurids which were more diverse in Appalachia than in Laramidia as well as a ton of other ornithischians. As far as I know sauropods weren't very diverse in Appalachia but I might need to do more research on this, still this variety of herbivores that tended to be very bulky as with the case of the nodosaurids likely had something to do with the adaptations of Appalachiosaurus. While it was itself a basal tyrannosaur, the only known specimen of Appalachiosaurus comes from a juvenile. As we can see in the image above, it already rivals the size of a juvenile T. rex specimen by the nickname of Jane, potentially indicating that adult Appalachiosaurus were just as large as some megatheropods if we go with the route that Appalachiosaurus also had the same ontogenetic niche-shifting as Tyrannosaurus. For those uninformed, this basically means younger individuals were more lightly built and hunted small to medium size prey that were rather speedy, while older more mature individuals hunted large and well armored prey with a set of adaptations to match. Overall, a very fascinating species to talk about. I will do this series a hundred times with Ekrixinatosaurus.
I hear a rumble in the mountains.
