Hylaeosaurus ("forest lizard") was a nodosaurid ankylosaur from the Early Cretaceous of England. It was the third dinosaur to be named.
In The Land Before Time
Some Hylaeosaurus appear in The Land Before Time IV: Journey Through the Mists, in the crowd scene after the longneck herd arrives.
- The character Rooter, from The Land Before Time was also proposed to be a Hylaeosaurus, but it is more likely he is based on reconstructions of Scolosaurus.