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The Isle of Wight pterosaur
 The Isle of Wight pterosaur
The new Isle of Wight pterosaur
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Unique flying reptile
While dinosaurs were the most important land animals during the Mesozoic era, flying over their heads was a major group of flying reptiles, the pterosaurs. Unlike bats, which fly with skin stretched between all of their fingers, and unlike birds, which fly with feathers, pterosaurs had a unique kind of wing in which a single hugely-enlarged finger supported a wing membrane stretched between the finger and the body and leg.
In the past, this wing form was often thought to have been inferior to bat and bird wings. But given that pterosaurs inhabited the skies from the Late Triassic to the end of the Cretaceous (a period of about 165 million years) and included the largest flying animals of all time (the biggest of them had wingspans exceeding 10 metres), they were in fact a phenomenal success story.
A new kind of pterosaur
Only one kind of pterosaur is well known in the Lower Cretaceous rocks of the Isle of Wight, an unusual long-skulled form with odd petal-shaped teeth called Istiodactylus latidens. Other fragments from the Isle of Wight have long suggested that other kinds of pterosaurs were present there, but until recently there had been no way of knowing what kinds of pterosaurs these were. This changed in 2002, when a partial skull of a completely new kind of Isle of Wight pterosaur was discovered.
Fang-toothed ornithocheirids
As shown by the presence of enlarged, fang-like teeth at its jaw tips, this new pterosaur belonged to the long-skulled, predatory group called the ornithocheiridae. Ornithocheirids have been known since 1859, but the English fossils on which the group was based were all incomplete and unimpressive. Beginning in the 1970s, many excellent ornithocheirid skeletons have more recently been discovered in the mid Cretaceous rocks of Brazil and these have provided a wealth of information on ornithocheirid anatomy, evolution and diversity.
Although the new Isle of Wight specimen is not as complete as the best Brazilian specimens, it has a unique tooth configuration and represents an entirely new kind of ornithocheirid. Like several of the Brazilian ornithocheirids, it has a keel-like crest running along the top of its snout. Exactly why some ornithocheirids had these remains controversial, but possibly they helped these pterosaurs drag their beaks through the water when they grabbed prey from the water surface. It has also been suggested that the crests were display devices only present in adult males.
Bony crests
The Isle of Wight specimen is even more remarkable, however, in possessing not only a keel-like snout crest but also a backward-projecting bony crest. This is similar to that of the famous North American Pteranodon (itself not an ornithocheirid but a distant relative).
No ornithocheirid was thought to have a crest like this until 2000, when a new Brazilian species showed that some of them did. The Isle of Wight ornithocheirid appears to be a close relative of this Brazilian form, so we now have two ornithocheirids with Pteranodon-like crests. It's odd that, while ornithocheirids have been known since 1859, these two new kinds, both with the same kind of crest yet separated by thousands of kilometres, have each been discovered within the space of just two years.
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