Xiongguanlong baimoensis, a theropod dinosaur, lived during the Early Cretaceous period. It is known for its elongated skull and robust jaw, suggesting a mix of carnivorous and omnivorous diet. This species bridges the gap between early tyrannosauroids and the larger Tyrannosaurus rex.

Xiongguanlong baimoensis is a genus of tyrannosauroid dinosaur that lived during the Early Cretaceous period, approximately 125 to 100 million years ago. Fossil evidence suggests that it inhabited what is now known as northwestern China, specifically the Gansu Province. The region during the Early Cretaceous would have been part of the ancient landmass called Laurasia.

During the Early Cretaceous, the area where Xiongguanlong baimoensis lived was characterized by a semi-arid climate with seasonal variations. The environment likely consisted of floodplains, river systems, and possibly forested areas. The climate would have supported a diverse range of plant life, including conifers and early angiosperms, providing ample food resources for herbivorous dinosaurs and subsequently for carnivorous predators like Xiongguanlong.

Xiongguanlong baimoensis occupied a niche as a mid-sized predator. It likely preyed upon smaller herbivorous dinosaurs and possibly scavenged for carrion. Its presence indicates an ecosystem with a complex food web, where it played an important role as a carnivore controlling the population of other species. The adaptations of Xiongguanlong, such as its long legs, suggest it was a capable runner, which would have been beneficial for both hunting and avoiding larger predators.