Pterosaurs are an extinct clade of flying reptiles in the order Pterosauria. They existed during most of the Mesozoic: from the Late Triassic to the end of the Cretaceous. Pterosaurs are the earliest vertebrates known to have evolved powered flight. Their wings were formed by a membrane of skin, muscle, and other tissues stretching from the ankles to a dramatically lengthened fourth finger.
Pterosaur
Conical tooth, possibly from Coloborhynchus
The skull of Thalassodromeus
A neck vertebra of Arambourgiania
Reptiles, as commonly defined, are a group of tetrapods with an ectothermic ('cold-blooded') metabolism and amniotic development. Living reptiles comprise four orders: Testudines (turtles), Crocodilia (crocodilians), Squamata, and Rhynchocephalia. As of May 2023, about 12,000 living species of reptiles are listed in the Reptile Database. The study of the traditional reptile orders, customarily in combination with the study of modern amphibians, is called herpetology.
Reptile
Reptiles, from Nouveau Larousse Illustré, 1897–1904, notice the inclusion of amphibians (below the crocodiles)
"Antediluvian monster", a Mosasaurus discovered in a Maastricht limestone quarry, 1770 (contemporary engraving)
The first reptiles had an anapsid type of skull roof, as seen in the Permian genus Captorhinus