Dimorphodon daiˈmɔː(r)f.ə.dɑn ("Two-form Teeth") was a genus of medium-sized (wing span 1.6 m., length of skull 22 cm.) pterosaur from the Early Jurassic Period (180-170 million years ago). Today, it lives on Dinotopia, and used as messengers, conveying messages across the island. It was named by paleontologist Richard Owen in 1859. Dimorphodon means "two-form tooth" (Greek δι/di meaning 'two', μορφη/morphe meaning 'shape' and οδον/odon meaning tooth), referring to the fact that it had two distinct types of teeth in its jaws - which is comparatively rare among reptiles.
It had a large, bulky skull whose weight was reduced by large cavities separated from each other by thin bony partitions. Its structure, reminiscent of the supporting arches of a bridge, prompted Richard Owen to declare that, in far as achieving great strength from light-weight materials was concerned, no vertebrae was more economically constructed. Otherwise, of course, the body structure of Dimorphodon displays many primitive characters, such as a very small brain-pan. The neck was strong and flexible and may have had a membraneous pouch on the under side.
Our knowledge of how Dimorphodon lived is also very small. It probably inhabited coastal regions and had a very varied diet.
Fossil remains have been found in England. Mary Anning made the first Dimorphodon (D. macronyx) discovery, at Lyme Regis in Dorset, UK in 1828. This region of Britain is now a World Heritage Site, dubbed the Jurassic Coast. Dimorphodon was approximately 1 metre (3.3 ft) long, with a 1.4 meter (4.6 ft) wingspan.
It has been argued that Dimorphodon was a biped, though fossilised track remains of other pterosaurs (ichnites) show a quadrupedal gait while on the ground. Its teeth and jaws suggest it was, like most pterosaurs, a piscivore (fish eater), although until quite recently it was suggested that it hunted small land animals. Most depictions give it a puffin-like 'beak'.
Dimorphodon lived approximately 200 million to 180 million years ago.