Rhabdodontids were herbivorous ornithopod dinosaurs from the Cretaceous Period. Rhabdodontids were similar to large, robust "hypsilophodonts", with deep skulls and jaws. The family was first proposed by David B. Weishampel and colleagues in 2002. The rhabdodontids were defined as "the most recent common ancestor of Zalmoxes robustus and Rhabdodon priscus and all the descendants of this common ancestor". In 2005, Paul Sereno defined the family as "the most inclusive clade containing Rhabdodon priscus but not Parasaurolophus walkeri". The Rhabdodontidae includes the type genus Rhabdodon, Zalmoxes, Mochlodon and possibly Muttaburrasaurus. Rhabdodontid fossils have been found in Europe and Australia in formations dating from the Early to Late Cretaceous, 100 to 66 million years ago. Ősi et al.