Dinosaurs · Large ornithopod

Gilmoreosaurus

Say it GIL-more-oh-SORE-us. The name means ‘Gilmores lizard’.

Gilmoreosaurus beside a person 1.75 m tall. Ticks mark every metre.Body shape drawn for this site, showing the general build of large ornithopods

Length: 6 m
Diet: Plant-eater
When: Late Cretaceous76 to 70 million years ago
Fossils found in: China
Named by: Brett-Surman (1979)
Family tree: Dinosauria › Ornithischia › Ornithopoda › Hadrosauridae

Where Gilmoreosaurus sits in the age of dinosaurs.Periods from the ICS chart; dinosaur dates from the Natural History Museum

Large ornithopods. Big plant-eaters that walked on two or four legs, including the duck-billed dinosaurs. See all 36

Lived at the same time

Alectrosaurus · same country
Archaeornithomimus · same country
Microceratus · same country
Mononykus · same country
Sonidosaurus · same country
Tanius · same country
Bactrosaurus · same country
Micropachycephalosaurus · same country

Other large ornithopods

Corythosaurus Late Cretaceous
Edmontosaurus Late Cretaceous
Lambeosaurus Late Cretaceous
Rhabdodon Late Cretaceous
Parasaurolophus Late Cretaceous
Prosaurolophus Late Cretaceous
Hadrosaurus Late Cretaceous
Kritosaurus Late Cretaceous

Source: Gilmoreosaurus in the Natural History Museum Dino Directory, read 12 November 2026. Sizes are the museum's estimates for a typical adult. "Lived at the same time" lists dinosaurs whose dates overlap, which does not always mean they met.