Paleontologists have identified a new species of extinct crocodyliform from the fossilized remains of a juvenile individual found in southwest Montana, the United States. The newly-described species lived at the edge of the ancient Western Interior Seaway about 95 million years ago (Late Cretaceous epoch). Named Thikarisuchus xenodentes, the ancient creature was a type of neosuchian. The specimens also presented clues about Thikarisuchus xenodentes’ newly-named family group Wannchampsidae and a similar group found in Eurasia known as Atopasauridae. A new, diminutive, heterodont neosuchian from the Vaughn member of the Blackleaf Formation (Cenomanian), Southwest Montana, and implications for the paleoecology of heterodont neosuchians.