Stegosaurus from Planet Dinosaur.

Stegosaurus (roof lizard or covered lizard) was a ornithoschian dinosaur from Late Jurassic North America.  It was the largest stegosaurid as well as the base species.


Stegosaurus was a herbivorous dinosaur.  It was discovered in the upper Morrison formation 1877 by Othniel Charles Marsh.  Recently, a new species has been discovered in Portugal.  Four species have been identified so far:

  • S. armatus (Marsh, 1877)
  • S. stenops (Marsh, 1887)
  • S. sulcatus (Marsh, 1887)
  • S. longispinus (Gilmore, 1914)

Due to its thagomizer and osteoderms, Stegosaurus is one of the most recognizable dinosaurs.  Its thagomizer is used to defend itself from predators and used to fight off rivals.  Its osteoderms were probably used for intimidation and display.  Stegosaurus flushed blood into the osteoderms to create a red, fierce colouring when suprised.  During the Jurassic, many theropod dinosaurs like Allosaurus and Saurophaganax existed so it needed to be in groups.  Loads of fossils of Stegosaurus, as well as other dinosaurs, have been discovered in the same place, suggesting a natural predator trap.  The Stegosaurus would drink from a river and become stuck in thick mud, causing it to starve.  Predators would come and attempt to kill it but then they would become stuck themselves.

In Walking with Dinosaurs

Stegosaurus appeared in the episode `Time of the Titans.`  A male Stegosaurus wandered to a pond to drink with the cresh of baby Diplodocus.  Suddenly, a pair of Allosaurus appeared.  Panicked, the Stegosaurus swinged its thagomizer at a baby Diplodocus, killing it.  The Stegosaurus flushed blood into its osteoderms to intimidate the Allosaurus.  The Allosaurus, who was confused and intimidated by the display, backed down.  The Stegosaurus continued drinking.

Stegosaurus in Walking with Dinosaurs.

In Planet Dinosaur

Stegosaurus appeared in the episode `Fight for Life`.  A herd of Stegosaurus and Camptosaurus were browsing.  The two species were working together.  The Stegosaurus were the defense and offense of the group whilst Camptosaurus were the scouters, always keeping a look out.  However, despite being a team, the Stegosaurus would budge the Camptosaurus to get at their food.  The Camptosaurus however, could still do the same.  Then, the Camptosaurus saw an Allosaurus in the distance which was waiting there.  They alerted the rest of the group but, then, the Allosaurus vanishes.  Just as the group began to settle down, the Allosaurus came charging.  The group scattered in all directions, trying to escape.  The Stegosaurus were too slow to run though.  The Allosaurus stopped chasing the Camptosaurus, realising that they were too far away, and turned towards the Stegosaurus instead.  It ran towards an individual, who was swinging its tail at it.  The Allosaurus circles it, narrowly missing the Stegosaurus' thagomizer, and then, dashes towards a juvenile.  The Allosaurus bites one of its osteoderms then its side.  It then bit the juvenile's neck but, then, suddenly, an adult Stegosaurus whacked the Allosaurus with its thagomizer!  The Allosaurus, laying on the ground in agony, watched as the group staggered away.

In The Ballad of Big Al

A Stegosaurus was seen with a group of Othnielia.  The Othnielia feed where the Stegosaurus stepped.

A dead Stegosaurus was seen stuck in a bog near a lake.  An Allosaurus was seen next to it, also stuck.  Another Allosaurus came to eat the Stegosaurus but got stuck as well.

A dead Stegosaurus in the Ballad of Big Al.

A pair of Stegosaurus came to a lake to mate.  However, Big Al came to the lake to drink.  Because of the smell of blood on his mouth, he made the pair nervous.  The pair then drove him away so they could mate in peace.

In Primeval

A Stegosaurus appeared in Series 4 Prequel Episode 1 where it went on a rampage in the House of Commons. Its fate was unknown.