A
pterosaur ("winged lizard") was a flying reptile of the order Pterosauria. They existed from the late
Triassic to the
Cretaceous periods (from 228 to 65 million years ago). The earlier species had long, fully-toothed jaws and long tails, while later forms had a stump for a tail, no teeth and a jaw more like a beak than the elongated jaw of the earlier species.
At least 60 genera of pterosaurs have been found ranging in size from a small bird to wingspans in excess of 40 feet. The wings were thin membranes of skin, similar to the wings of bats, attached to the extremely long fourth finger of each arm and extending along the sides of the body. There is no fossil evidence of feathers.
Their bones were hollow and had openings at each end. Unlike typical reptiles, pterosaurs had a breastbone that was developed for the attachment of flight muscles and a brain that was more developed than comparable dinosaurs of similar sizes.
Most paleontologists now believe that pterosaurs were adapted for active flight, not just gliding as was earlier believed.
Examples of pterosaurs include
- Pterodactyl, with a wingspan of about 50-75 cm (20-30 inches), that lived during the late Jurassic on lake shores.
- Dsungaripterus, with a wingspan of 3 metres (10 feet) wingspan, an unusual bony crest running along its snout, and long, narrow, curved jaws with a pointed tip, that lived during the early Cretaceous period.
- Pteranodon, 1.8 metres (six feet) long with a wingspan of 7.5 m (25 feet), that lived during the late Cretaceous period.
- Quetzalcoatlus, with a wingspan of 12 m (40 feet) and a weight of only about 50 kg (110 pounds), that lived during the late Cretaceous period.