Peteinosaurus was one of the earliest Pterosaurs, dating to the Mid Triassic Period, around(225-200)Though not the earliest Pterosaur known, with Early Triassic relatives, it was one of the very earliest Pterosaurs to become widely successful, clearly establishing reptiles as 'the new masters of the air.
It was a comparatively small Pterosaur of the characteristic long-tailed Rhamphorhynchids, at around 40-60 centimetres in wingspan. Its diet would have consisted largely of insects, such as Dragonflies, due to its tiny but very sharp needle-like teeth.
A Peteinosaurus is chasing dragonflys at the beggining of the episode. Kenneth Branagh explain that this little pterosaur has little sharp teeth, efficient to eat little insects.
At the second part of the episode, a peteinosaurus is shown cooling him from the drought in a rest of a stream.