Pteranodon
Pteranodon (; from Greek πτερόν ( pteron, "wing") and ἀνόδων (anodon, "toothless") is a genus of pterosaur that included some of the largest known flying reptiles, with wingspans over 8 meters (26 feet). They lived during the late Cretaceous geological period of North America in present-day Kansas, Alabama, Nebraska, Wyoming, and South Dakota. More fossil specimens of "Pteranodon" have been found than any other pterosaur, with about 1,200 specimens known to science, many of them well preserved with nearly complete skulls and articulated skeletons. It was an important part of the animal community in the Western Interior Seaway.
Rodan (film)
Shigeru confirms that the creature he saw did indeed resemble a "Pteranodon", and that it had eaten all of the Meganulon. He and a group of police and scientists once again descend into the mine and enter the cave where the egg had been. They are able to recover a fragment of the shell before a rock slide forces them to flee back to the surface. In the lab, Dr. Kashiwagi is able to determine the size of the egg and its age: 200 million years old. After amassing the evidence, Kashiwagi calls a meeting with members of the town, along with members of the Japanese Self-Defence Force, to communicate his findings. He tells the men that the UFO seen flying all across the world at supersonic speeds is a gigantic pterosaur he has dubbed Rodan. How Rodan could have resurfaced after millions of years is also a mystery, but Kashiwagi theorizes that nuclear bomb testing, which loosened the Earth's crust and opened cavities to long buried crevices and caves, might be the possible cause.