Yutyrannus huali was a large theropod from the Early Cretaceous period discovered in the Yixian Formation in northeastern China. It is especially famous for being the largest known dinosaur with direct evidence of feathers, which has had a huge impact on how we understand the appearance and biology of large tyrannosauroids.

It measured approximately 9 meters in length and weighed between 1 and 1.5 tons, making it a top predator in its ecosystem. Its skull was long and robust, with large, serrated teeth, while its arms were still relatively developed compared to later tyrannosaurids like Tyrannosaurus rex.

Yutyrannus's body was covered in feather-like filaments, mainly on its neck, back, and tail, functioning as thermal insulation—an important adaptation to the colder, seasonal climate of the region where it lived. This indicates that down was not restricted to small dinosaurs but was also present in some large carnivores.

(probably my last LoRA of 2025)