The Quetzalcoatlus is a pterosaur, and the second largest known. They appear in the third film chasing Buck, Crash and Eddie while they were flying to save Sid in Lava Falls. They almost caught them but Buck piloted a pteranodon to Lava Falls. He pulled up sharply in front of a lava waterfall, but the Quetzalcoatlus were unable to pull up fast enough and they plunged straight into the lava.
Just like other pterosaurs, they were not actually dinosaurs. A lone Quetzalcoatlus was flying down a cliff near a Momma Dino's feeding spot. Momma Dino brings a Archaeopteryx for her young, but a sloth named Sid throws it off the cliff (thinking it can fly) because he wants to raise the Baby Dinos vegetarian. The flightless bird instantly falls, and the quetzalcoatlus finds it an easy meal, swooping down and eating it in one bite.
Not long after, several Quetzalcoatlus was resting on the large rocks of Lava Falls, waiting for easy prey. All a sudden a pteranodon called Roger flew nearby. All of the hungry flying reptiles chase the smaller pterosaur rode by a weasel named Buck and two opossums named Crash and Eddie. Some Quetzalcoatlus lunge towards Roger who dodge their lunges. Buck leads the pterodactyl into rocky tunnels, hoping to confuse the flying predators. The mammals reach a Brachiosaurus feeding spot with berries. Buck and the opossums use them as weapons, knocking out several Quetzalcoatlus and inflating one with Crash stating : "Hasta La Vista, Birdy". Both reptiles dodge the Brachiosaurus', leaving five Quetzalcoatlus chasing Buck, Crash and Eddie. The mammals avoid crashing into Lava Falls, but unfortunately for the Quetzalcoatluses; they crash to the lava and are burned alive.