Quetzalcoatlus was a pterodactyloid pterosaur known from the Late Cretaceous of North America (Maastrichtian stage, about 68–65.5 million years ago), and one of the largest known flying animals of all time. It was a member of the Azhdarchidae, a family of advanced toothless pterosaurs with unusually long, stiffened necks. Its name comes from the Mesoamerican feathered serpent god Quetzalcoatl.
The first Quetzalcoatlus fossils were discovered in Texas, from the Maastrichtian Javelina Formation at Big Bend National Park (dated to around 68 million years ago) in 1971 by a geology graduate student from the University of Texas at Austin’s Jackson School of Geosciences, Douglas A. Lawson. The specimen consisted of a partial wing (in pterosaurs composed of the forearms and elongated fourth finger), from an individual later estimated at over to 10 m (33 ft) in wingspan.
Skull material (from the unnamed smaller species) shows that Quetzalcoatlus had a very sharp and pointed beak, contrary to some earlier reconstructions that showed a blunter snout, based on the inadvertent inclusion of jaw material from another pterosaur species, possibly a tapejarid or a form related to Tupuxuara. A skull crest was present but its exact form and size is still unknown.
The nature of flight in Quetzalcoatlus and other giant azhdarchids is poorly understood. Their method of flight depends largely on their weight, which has been controversial, with widely differing masses favored by different scientists. Some researchers have suggested that these animals employed slow, soaring flight, while others have concluded that their flight was fast and dynamic. In 2010, Donald Henderson argued that the mass of Q. northropi has been underestimated, even the highest estimates, and that it was too massive to have achieved powered flight. Henderson argued that it may have been flightless.
Size comparison of Q. northropi (green), the unnamed smaller species (blue), and a human