Dinosaurs · Prosauropod

Riojasaurus

Say it ree-oh-hah-sore-us. The name means ‘[La] Rioja lizard’.

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

Length: 5.2 m
Diet: Plants, perhaps animals too
When: Late Triassic221 to 210 million years ago
Fossils found in: Argentina
Named by: Bonaparte (1969)
Family tree: Dinosauria › Saurischia › Sauropodomorpha › Anchisauria › Melanorosauridae

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

Prosauropods. Early long-necked plant-eaters, relatives of the sauropods. See all 16

Lived at the same time

Other prosauropods

Coloradisaurus Late Triassic
Guaibasaurus Late Triassic
Mussaurus Late Triassic
Melanorosaurus Late Triassic
Thecodontosaurus Late Triassic
Plateosaurus Late Triassic
Massospondylus Early Jurassic
Jingshanosaurus Early Jurassic

Source: Riojasaurus 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.