Xenovenator

What it was like

Xenovenator was a small, bird-like troodontid with a very odd head. The top of its skull was thick, swollen and rough, a little like the domes of pachycephalosaurs.

That thick skull roof may mean these animals pushed or butted each other, a kind of behavior never shown before in this group of feathered dinosaurs. For now that idea is a suggestion, not a certainty.

Its world

It lived about 84 to 72 million years ago, in the Late Cretaceous, in what is now Mexico and the United States. Its fossils come from the Cerro del Pueblo Formation in Mexico and the Kirtland Formation in New Mexico, where the horned Pentaceratops and the tyrannosaur Bistahieversor also lived.

How it was found

Rivera-Sylva and colleagues named Xenovenator in 2026 from pieces of the skull. Fossils from New Mexico that had been given another name were moved into the same genus.