Claosaurus agilis

Claosaurus is a genus of hadrosauroid dinosaur that lived during the Late Cretaceous Period (Santonian-Campanian) of what is now North America. The type and only known valid species is Claosaurus agilis. Traditionally classified as an early member of the family Hadrosauridae, a 2008 analysis found Claosaurus to be outside of the clade containing Hadrosaurus and other hadrosaurids, making it the closest non-hadrosaurid relative of true hadrosaurids within the clade Hadrosauromorpha.