Ichthyosaurus (name meaning "Fish Lizard") is a genus of ichthyosaurs that originated during the Early Jurassic period in what is now Europe and Asia. Measuring around 3 meters long and weighing 220 kg, it is among the best-known ichthyosaur, in addition to being the name-sake.
In the episode, "Cruels Seas," a pod consisting of nine individual Ichthyosaurus were brought to the park from Late Jurassic Europe, 149 million years ago. They reside in the Primeval Aquarium Enclosure.