Reptiles are a monophyletic groups of ancient tetrapods.
The first reptiles appeared during the carboniferous, and had common traits like laying eggs and having scales. The first reptiles were terrestrial, but after many niches opened up for them, they became aquatic (like marine reptiles) and aerial (like pterosaurs).
Groups[]
Dinosaurs
Mosasaurs
Pterosaurs
Plesiosaurs
Ichthyosaurs
Turtles
Lizards
Snakes
Crocodilians