Xenovenator espinosai Xenovenator

Xenovenator (“strange hunter”) is an extinct genus of troodontid theropod dinosaurs known from the Late Cretaceous (Campanian age) of North America. The type species of the genus, Xenovenator espinosai, is known from fragmentary skull bones found in the Cerro del Pueblo Formation of Mexico. It is characterized by an unusually expanded and rugose skull roof, somewhat comparable to that seen in pachycephalosaurs. This may imply Xenovenator individuals engaged in combat with other members of their species, a behavior for which adaptations had not been previously observed in non-avian paravians.

Saurornitholestes robustus, known from the Kirtland Formation of New Mexico, United States, may also belong to this genus, although it lacks the characteristic domed skull roof of X. espinosai.