Dinosaurs · Large ornithopod

Secernosaurus

Say it see-ser-noh-sore-us. The name means ‘separated lizard’.

Secernosaurus 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: 3 m
Diet: Plant-eater
When: Late Cretaceous71 to 66 million years ago
Fossils found in: Argentina
Named by: Brett-Surman (1979)
Family tree: Dinosauria › Ornithischia › Ornithopoda › Hadrosauridae

Where Secernosaurus 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

Neuquensaurus · same country
Noasaurus · same country
Saltasaurus · same country
Abelisaurus · same country
Dreadnoughtus · same country
Puertasaurus · same country
Aucasaurus · same country
Gasparinisaura · same country

Other large ornithopods

Hypacrosaurus Late Cretaceous
Saurolophus Late Cretaceous
Corythosaurus Late Cretaceous
Edmontosaurus Late Cretaceous
Gilmoreosaurus Late Cretaceous
Lambeosaurus Late Cretaceous
Rhabdodon Late Cretaceous
Parasaurolophus Late Cretaceous

Source: Secernosaurus 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.