Hypsilophodontid

Hypsilophodontids are a group of small  Dinosaurs. The group is called after the genus Hypsilophodon. Which dinosaurs belonged to this group has been a subject of debate for a long time. This debate has influence on which dinosaurs appear in the Jurassic Park novels

published a review article in which he made a classification of all species. For instance, he placed Dryosaurus outside of this family.

Other paleotologists like Jack Horner think that Dryosaurus did belonged to the Hypsilophodontid family.

Jurassic Park Franchise
A group called Hypsilophodontids appears in both novels. It is unclear what dinosaur species belonged to this group.

Jurassic Park (novel)
In the chapter Control a list of all dinosaurs in the park appears. One of them is Hypsilophodontids These animals are first seen during the Park Drive in the Hypsilophodon Highlands. The logic conclusion would be that these animals are Hypsilophodons. The fact that the animal count screen is using the generic term for a specific species is hardly unusual considering its use of "Pterosaurs" instead of "Cearadactylus". However, there are indication that other species than Hypsilophodon belonged to this group.

During the Park Drive this information is given:

Hypsilophodontids are the gazelles of the dinosaur world: small, quick animals that once roamed everywhere in the world, from England to Central Asia to North America.

Hypsilophodons are never found outside Europe.