Pterodactylus ("winged finger") is a genus of pterosaurs, whose members are popularly known as pterodactyls. It was the first to be named and identified as a flying reptile. Pterodactyls are any of a number of genera of flying reptiles of the extinct order Pterosauria, from the Jurassic and Cretaceous periods, having a highly reduced tail and teeth, birdlike beak and and a wingspan of 3.3 ft or less. Pterosaurs ("winged lizard") were flying reptiles of the order Pterosauria. Pterosaurs are the earliest vertebrates known to have evolved powered flight.