pterosauria

Pterosauria is an extinct order of flying reptiles that lived from the Late Triassic to the end of the Cretaceous, roughly 228 to 66 million years ago. They are part of Archosauria and, within that group, are closer to dinosaurs and birds than to crocodilians. Pterosaurs were the first vertebrates to achieve powered flight and occupied a wide range of ecological roles.

A defining feature of pterosaurs is a wing membrane supported primarily by an elongated fourth finger, with other digits reduced. Their skeletons were generally light and hollow, and many possessed pycnofibers—hair-like filaments—that may have provided insulation. Flight adaptations varied across groups, and some lineages show substantial cranial crests, dental diversity, and specialized feeding strategies.

Two major clades are commonly recognized: Rhamphorhynchoidea, typically long-tailed and earlier in time, and Pterodactyloidea, which includes many later, shorter-tailed forms that diversified widely in body shape and ecology. Pterodactyloids became the dominant pterosaur group during the Jurassic and Cretaceous.

The size of pterosaurs ranged from small, with wingspans of about 20–50 centimeters in some taxa, to giants such as Quetzalcoatlus northropi with estimated wingspans approaching 10 meters. They inhabited coastal, marine, and inland environments, feeding on fish, small vertebrates, insects, and other prey depending on the lineage.

Pterosaurs went extinct at the Cretaceous–Paleogene boundary. Their fossil record provides key insights into the evolution of powered flight, vertebrate ecology, and Mesozoic ecosystems.