The Archosaurs Archosaur, (Greek for prevailing repitles ) are a taxonomic group of higher vertebrate animals that includes living and extinct dinosaurs, crocodiles and pterosaurs or flying reptiles. Some scientists believe that all the animals mentioned above should be included in a new taxonomic class called "Archosauria " which would eliminate the class "Birds " and it would separate the crocodiles, dinosaurs and reptiles pterosaurs. Others however prefer to include these within the class of the Diapsids, along with lizards, snakes and mosasaurs.