Hadrosaurs were members of the family hadrosauridae. Their most recognizable feature is a beak resembling a duck's. There was two subfamilies: hadrosaurinae and lambeosaurinae. Hadrosaurines mainly had no crests, though some had bumps on their noses or small points. Lambeosaurines had large crests. All could walk on either to legs or four.

The Land Before Time

Hadrosaurs vary in different appearance therefore have several Land Before Time terms based on their unique features. Bigmouths are Saurolophus and probably others such Edmontosaurus or Prosaurolophus. This name comes from their duck-like bill which were much large than other Hadrosauridae dinosaurs. Term, Swimmer also refers to Saurolophus (and perhaps others) due to the fact they live around water. This is not actually accurate, as it is based on theories that the crests were used as snorkels or aqua-lungs and a set of footprints that appeared to have webbed toes. Hollowhorns refers to are any of the Lambeosaurines, named after the hollow crests. Duckbill is a name used in a single scene in The Land Before Time V to describe a hadrosaur skeleton. Cera's father says that "everyone knows how stupid Duckbills are", which offends Ducky's mother. However this term references an animal that had not even evolved until after the dinosaurs died out.

Species appearing in The Land Before Time