Khankhuuluu

Khankhuuluu ( ; ) is an extinct genus of early tyrannosauroid theropod dinosaurs from the Late Cretaceous of what is now the Gobi Desert in Mongolia. The genus contains a single species, Khankhuuluu mongoliensis, known from several skull bones and two partial skeletons, including shoulder, pelvic, and hindlimb bones, and several vertebrae from the back and tail. The remains were discovered in 1972 and 1973 and first described in 1977 as belonging to the Chinese Alectrosaurus. Later researchers recognized the uniqueness of the bones, and they were eventually named as belonging to a new species in 2025. Khankhuuluu is a medium-sized tyrannosauroid with a shallow skull and long, slender legs. Its skeleton demonstrates a unique combination of anatomical traits seen in both earlier-diverging (basal) tyrannosauroids and the later-diverging (derived) tyrannosaurids.

Khankhuuluu is known from the Bayanshiree Formation, which dates to around the Turonian–Santonian ages. The formation has yielded abundant fossils of diverse dinosaurs including various theropods, ankylosaurs, marginocephalians, hadrosauroids, and sauropods, in addition to pterosaurs, crocodylomorphs, turtles, and fish. These fossils were deposited in an environment with meandering rivers.