Herrerasaurus

Herrerasaurus was from the triassic period and the first Dinosaur larger than 9 feet, growing up to 18 feet long. It is unknown if Herrerasaurus was a Dinosaur or an close cousin.

In Jurassic Park
Herrerasaurus is not seen in person in the Jurassic Park movies, but its name is on a map inside of the Jeep's brochure in Jurassic Park. Herrerasaurus is also seen in Jurassic Park III: Park Builder.