Quetzalcoatlus - Sky Sailors

Three Quetzalcoatlus northropi soar over a flooded, mud-choked river in Late Cretaceous Texas. Far below, three massive Alamosaurus lumber slowly towards a stand of conifer trees.

Quetzalcoatlus is well known as the "biggest" pterosaur, having a 40-foot wingspan, though the recently discovered Hatzegopteryx from Transylvania is even larger. Both are members of the giant Azdarchid family, one of the last great clans of pterosaurs.