Ultrasaurus is a large sauropod from the Cretaceous period that lived in South Korea. A holotype specimen of Ultrasaurus from the Jurassic period in Colorado turned out to be a mixture of Supersaurus and Brachiosaurus, meaning it was not even a true genus. Ultrasaurus as used for the latter use is now just an alternate name for the dinosaur officially known as Supersaurus.
Jurassic Park franchise
Ultrasaurus appeared in the website Jurassic Park: Institute on Dinopedia.
The Ultrasaurus are located in a section called Ultrasaur Lagoon. They spend most of their time in the water, eating aquatic plants. One Ultrasaurus is an adult, the other a smaller infant. They share their section with Psittacosaurus.
Behind the Scenes
Early in the development of the first film, Phil Tippett lobbied for the Apatosaurus from the novel to be replaced by either Ultrasaurus or Brachiosaurus due to being being larger then Apatosaurus and a much more interesting design.
Oddly (most likely due to mechanical functions), the adult Ultrasaurus at the Hollywood version of Jurassic Park: The Ride seems to bend its neck up and down from the sides instead of from the front and back, and in all versions seems to have its head always facing straight forward even when bending its neck.