Istiodactylus was a medium sized pterosaur from the Early Cretaceous period. Discovered on the Isle of Wight, Istiodactylus latidens was originally placed in the genus Ornithodesmus by H.G. Seeley in 1901 and was fully described by R.W. Hooley in 1913. The type species of the genus Ornithodesmus, however, was later discovered to be based on bones belonging to a theropod dinosaur, which meant a new genus had to be named for O. latidens. This species was assigned to its own genus Istiodactylus by Howse, Milner, and Martill in 2001. Since then, a second species, I. sinensis from China, has also been discovered.
This was a moderately large pterosaur; its skull was 65 cm long, and its wingspan was probably in the 5 meter range, making it about half the size of Pteranodon. Because of the flat, rounded shape of its beak, Istiodactylus is sometimes referred to as a "duck billed pterosaur". However, unlike a duck, it had small, sharp teeth that allowed the capture of fish. Recent studies, however, show that it might had been a scavenger