The Pterosaurs, meaning winged lizards, often called pterodactyls were flying reptiles of the clade Pterosauria. They appeared in Late Triassic and persisted until the end of the Cretaceous Period when they met extinction with the dinosaurs. The Pterosaurs were the first vertebrates to evolve flight.
Some 60 genera of pterosaurs have been discovered, ranging in size from that of a small bird to a wingspan of more than 30 feet. The first pterosaur fossil was discovered in the late Jurassic Solnhofen limestone in 1784, and since then 29 other kinds of pterosaurs have been found in the Solnhofen site. Once believed to be gliders, paleontology now widely accepts that they were active flyers.
Hollow bones of Pterasaurs resulted in poor preservation as fossils. Competition with early bird species may have contributed to a decline in pterosaurs so that, by the end of the Cretaceous, only large species of pterosaurs still existed. All went extinct at the end of the Cretaceous period, along with all the dinosaurs.