Riojasaurus was a herbivorous prosauropod dinosaur. It was one of the earliest of the large, plant-eating dinosaurs. "Riojasaurus" lived during the Upper Triassic, roughly 225 to 219 million years ago. Fossils have been found in La Rioja Province in Argentina. There are include incomplete skeletons from about 20 individuals.This dino was 30ft tall and 10ft long.