Because Iguanodon is one of the first dinosaur genera to have been named , numerous species have been assigned to it . While never becoming the wastebasket taxoned several other early genera of dinosaurs became ( such as Megalosaurus ) , Iguanodon have had a complicated history , and its taxonomy continue to undergo revisions . Although Gregory Paul recommended restricting I. bernissartensis to the famous sample from Bernissart , ornithopod workers like Norman and McDonald have disagreed with Paul 's recommendations , except exercising caution when accepting records of Iguanodon from France and Spain as valid .