Experts believe they are more closely related to crocodiles and dinosaurs and birds than they are to lizards and snakes
https://www.independent.co.uk/news/science/ancient-marine-reptile-snake-cartorhynchus-lenticarpus-a9
https://www.independent.co.uk/news/science/ancient-marine-reptile-snake-cartorhynchus-lenticarpus-a9