Martialotyrannus

Martialotyrannus is an extinct Gorgosaurus-sized Tyrannosaur that lived in what is now Mexico, Texas, New Mexico, South Dakota, and Montana during the Late Cretaceous (from 68 to 66 million years ago). They likely evolved from the same ancestors as Tyrannosaurus Rex, but Martialotyrannus went onto a completely different approach, they evolved to replace the Albertosaurines they killed off to extinction by becoming sleeker in build and faster animals. They were carnivorous and most likely preyed on Alamosaurus as one fossil site seems to show, where fossilized Alamosaurus fossils are next to Martialotyrannus fossils and both teeth and claws seems to fit the claw and bite marks on Alamosaurus bones. They may have also preyed on ceratopsids, hadrosaurs, and other dinosaurs, as well as pterosaurs and crocodilians when fully grown, but Martialotyrannus hatchlings most likely fed on insects, spiders, fish, and frogs. They may have went extinct due to the asteroid impact and its effects. With no Tyrannosaurs including Martialotyrannus, Alamosaurus hatchlings survived through the earliest part of the Cenozoic into adulthood and made it into modern times.