# Stegosaurus - Source: Kiddle (kids.kiddle.co), CC BY-SA 3.0, Kiddle encyclopedia, adapted from Wikipedia - Reading level: Grade 5 - Subjects: Dinosaurs, Science - Topics: stegosaurus, long, legs, plates, drawing, first - Length: 704 words, about 5 min - Published: 2025-10-17 - Original: - Page: - Open in Sprouts: ![Bałtów Park Jurajski 001.jpg](https://sprout.rootsofreason.org/media/kiddle-stegosaurus-facts-for-kids-b17216f502.jpg) ![Stegosaurus Senckenberg](https://sprout.rootsofreason.org/media/kiddle-stegosaurus-facts-for-kids-c4bc6a1df9.jpg) *Stegosaurus* ![Stegosaurus size](https://sprout.rootsofreason.org/media/kiddle-stegosaurus-facts-for-kids-69c07a19ac.png) The size of a *Stegosaurus* compared to a human ![Stegotooth](https://sprout.rootsofreason.org/media/kiddle-stegosaurus-facts-for-kids-157d71f14b.png) Stegosaurus tooth ***Stegosaurus*** (which means "roof-lizard") was a large plant-eating [dinosaur](https://sprout.rootsofreason.org/r/kiddle/dinosaur-facts-for-kids). It lived in what is now western North America. This amazing dinosaur lived during the Upper Jurassic period. This was about 155 to 145 million years ago. *Stegosaurus* is easy to recognize. It had two rows of kite-shaped plates on its back. It also had long spikes on its tail. These spikes and plates helped protect it. It lived alongside fierce meat-eaters like *Allosaurus* and *Ceratosaurus*. ## Discovering the Stegosaurus Scientists first found *Stegosaurus* fossils in 1877. Othniel Charles Marsh named it from bones found near Morrison, Colorado. These first bones led to the naming of the first *Stegosaurus* type: *Stegosaurus armatus*. Many different types of *Stegosaurus* have been found. - ***Stegosaurus armatus***: This was the first type discovered. Scientists have found over thirty skeletons of this species. It had four tail spikes and small plates. At 9 meters (30 feet), it was the longest *Stegosaurus* species. - ***Stegosaurus stenops***: Marsh named this type in 1887. It was found near Cañon City, Colorado. This is the most famous *Stegosaurus* species. We have at least one complete skeleton of it. It had large, wide plates and four tail spikes. *S. stenops* was shorter than *S. armatus*, growing to about 7 meters (23 feet). - ***Stegosaurus longispinus***: We know this type from one incomplete skeleton. *S. longispinus* had very long tail spikes. It was also about 7 meters (23 feet) long. ## How Stegosaurus Lived *Stegosaurus* was the biggest of the stegosaur family. It could grow up to 12 meters (39.4 feet) long. It weighed as much as 5,000 kilograms (5.5 tons). However, most were usually 7 to 9 meters long. ### Its Head and Diet The skull of *Stegosaurus* was long and thin. Its front legs were short. This meant its head was close to the ground, about 1 meter (3.3 feet) high. Because of this, it ate plants that grew low to the ground. It did not have front teeth. Instead, it had a beak covered in horn. Its chewing teeth were small and shaped like triangles. They did not grind food much. ### Its Brain and Nerves People often say the *Stegosaurus* brain was the size of a walnut. But it was actually several times bigger than a walnut. It also had a large group of nerves near its tail. These nerves helped control the back of its body. Some people even called this a "second brain." You can learn more about this in Dinosaur brains and intelligence. ### How it Stood *Stegosaurus* had very short front legs compared to its back legs. Its back legs had three short toes. Its front legs had five toes. All four legs had pads behind the toes to help support its weight. ## Stegosaurus in Pop Culture ![Dinosaurs Sci Am 1884](https://sprout.rootsofreason.org/media/kiddle-stegosaurus-facts-for-kids-cb285b55cc.png) An early drawing of *Stegosaurus* from 1884 *Stegosaurus* is one of the most famous dinosaurs. You can see it in movies, cartoons, comics, and as toys. For a long time, scientists only had small pieces of *Stegosaurus* fossils. This made it hard to draw what it really looked like. An early drawing of *Stegosaurus* was made in 1884. It showed the dinosaur standing on two legs with a long neck. It also had spikes all over its back and tail. This drawing was not very accurate. In 1891, Marsh published a more correct drawing of the *Stegosaurus* skeleton. Soon, *Stegosaurus* became one of the most drawn dinosaurs. Artist Charles R. Knight made his first drawing in 1897. It showed a single row of plates. Later, he drew it with a double row of plates. This drawing was used to create the puppet in the 1933 movie *King Kong*. ![Stegosaurus stenops model Smithsonian](https://sprout.rootsofreason.org/media/kiddle-stegosaurus-facts-for-kids-7d3430a2c2.png) A life-sized model of *Stegosaurus stenops* from around 1911 *Stegosaurus* made its first big public appearance as a paper model in 1904. This model had the double row of plates. It was shown at big events before moving to the Smithsonian National Museum of Natural History. Recently, on July 17, 2024, a large *Stegosaurus* skeleton called "Apex" was sold. It went for $44.6 million (£34 million) at an auction in New York City. This was the most money ever paid for a fossil! ## Picture credits - Jakub Hałun, CC BY-SA 3.0 () - EvaK, CC BY-SA 2.5 () - CC BY-SA 3.0 () - CC BY-SA 3.0 () - A. Jobin, Public domain () - Charles W. Gilmore, Public domain ()