Hadrosaurus is simultaneously a very important and a very obscure dinosaur. It was the first near-complete dinosaur skeleton ever to be discovered in North America (in 1858, on the coast of New Jersey ), and it gave its name to a populous class of herbivores--the hadrosaurs, or duck-billed dinosaurs. Celebrating this history, New Jersey named Hadrosaurus its official state dinosaur in 1991.
However, as far as the duck-billed dinosaurs are concerned, Hadrosaurus itself occupies the far fringes. To date, no one has discovered this creature's skull, so recreations are based on skulls of similar genuses, like Gryposaurus. And second, Hadrosaurus appears to be the only member of its own genus, prompting some paleontologists to believe that it may be a species of another genus of hadrosaur.
