Ankylosaurus was a large, armored dinosaur that lived during the late Cretaceous period, around 68 to 66 million years ago. It was known for its heavy body covered in bony plates and spikes, which provided protection from predators. Ankylosaurus could grow up to 30 feet long and had a distinctive club-like tail that it could use as a weapon. This dinosaur primarily fed on low-lying plants, using its beak-like mouth to clip vegetation. Fossils of Ankylosaurus have been found in North America, and it is often associated with other dinosaurs from the same era, such as Tyrannosaurus rex and Triceratops.