 Iguanodon gives its name to the unranked clade Iguanodontia , a very populous group of ornithopods with many species known from the Middle Jurassic to the Late Cretaceous . Aside from Iguanodon , the best @-@ known members of the clade include <unk> , Camptosaurus , Ouranosaurus , and the duck @-@ bills , or hadrosaurs . In older sources , Iguanodontidae was shown as a distinct family . This family traditionally has been something of a <unk> taxon , including ornithopods that were neither <unk> or hadrosaurids . In practice , animals like <unk> , Camptosaurus , <unk> , <unk> , <unk> , <unk> , Ouranosaurus , and <unk> were usually assigned to this family . 
