The Pterodactyl is a dinosaur seen in the prehistoric past in 199,997,682 BC. It is part of a death sequence in Journeyman Project Turbo (and original), it will attack Gage Blackwood if he lingers too long. It can be seen flying to the rightside of the 350 meter cliff, and also its shadow flies over the canyon.
In Pegasus Prime, in the 200,000,000 BC (2x10^8 BC) while Gage Blackwood is on an unstable island, Pterodactyls can be seen flying by in a couple of brief cutscenes; one on the leftside of the TSA platform near the cliff where Gage Blackwood is sent into the past, and near a second cliff with a river down below near the bridge to the Historic Log.
Behind the scenes[]
In Pegasus Prime rather than being eaten by a pterodactyl, if the Gage waits too long, the island becomes more and more unstable, until the island breaks apart, and Gage falls into the lava below, or becomes stranded and eaten by the denizens of the jungle (Hypsolophodon (sic)).
Pterodactyls actually existed around 150,000,000 to 140 million years ago in the late Jurassic. But still much younger than the dates given in the Journeyman Project and Remake.