“Roofed Lizard” discovered in Colorado in 1876 by M. P. Felch & described by Othniel C. Marsh in 1877. Stegosaurus lived during the Late Jurassic Period about 154 to 150 million years ago. It was 9-12 meters (30-40 ft.) in length, 5.8 meters (19 ft.) in height at the top of the plates, & 7 tons in weight and 2-3 foot long tail spikes (thagomizers) likely used in defensive combat. Its forelimbs were rather short in relation to its hind limbs, suggesting it was not capable of particularly swift motion. It had 17 bony plates that attached into the skin of the back that likely served as display structures. It was herbivorous with “a bite force less than half that of a Labrador retriever” meaning it was likely a browser of small, weak plants.
They are first seen on the Isla Nublar Jurassic Park when the tour group reaches the Stegosaurus Paddock situated in the volcanic plains of the south. It was described as ” 20 feet long with a bulky body, and vertical plates along his back. The tail had dangerous looking three foot spikes,” it had an “absurdly small head with a gaze like a very dumb horse.” They were afflicted with an unknown ailment that reoccurred every 6 weeks. The animal was described as having a peculiar odor “like rotting fish.” It had a dark purple tongue that, due to disease had “fine silvery blisters.” Their eyes became dilated despite the fact that the tranquilizers should have constricted the pupils, suggesting a “pharmacological effect.” The disease’s symptoms were characteristic of poisoning by West Indian Lilacs, however, the animals never ate the plants. It was revealed that they had been swallowing the plant while consuming gizzard stones, as some of the Lilac berries were stuck among the stones. Another was seen by Tim Murphy in the chapter “Tim,” he observed one walking while he was trapped in the car, and after he escaped, he chased it off by throwing rocks at it.
A Stegosaurus was again seen by Dr. Sarah Harding in her 1995 trip to Isla Sorna. Sarah Harding is brought back to consciousness on the riverbank on Isla Sorna by a Stegosaurus licking her. In her weakened state, she originally thought it was a horse , but upon reaching clarity of mind she realized its true identity. It was described as having a dark blue tongue, and warm spit, confirming its warm blooded metabolism, and its skin was was pebbled like a Rhino.
The Stegosaurs did not have any RANA DNA incorporated in it, and therefore did not breed. It had an expected population of 4, an actual population of 4, and an equilibrium population of 1. It was recorded as version number 3.9 at Isla Nublar.