Riojasaurus Characteristics

Riojasaurus measured 33 feet (10 metres) in length and weighed 1.1 tons. It was heavily built and had a bulky body and was quadrupedal, moving slowly around on 4 thickly built legs. Its leg bones were dense and massive for a prosauropod and its hinds limbs and fore limbs were not much different in size. Riojasaurus had relatively longer hands and feet than a sauropod and more of its digits were tipped with claws. Riojasaurus had a very long neck and a long tail. No skull was found with the first skeleton of Riojasaurus, but its long slender neck suggests that its head was quite small. Its vertebrae were made lighter by hollow cavities, and unlike most prosauropods, Riojasaurus had 4 sacral vertebrae instead of 3.

The teeth of Riojasaurus were spoon shaped and serrated. The upper jaw contained 5 teeth at the front, with 24 more behind them in a row that ended under the eyes.

Riojasaurus was a plant eater (herbivore) and fed up on foliage on tall conifer trees, raking off the leaves and needles with its spoon-like teeth. Riojasaurus used its flattened teeth to cut and grind plants. This huge dinosaur would have had to eat huge amounts of vegetation to sustain itself.

Riojasaurus was a sauropodomorpha, whose intelligence (as measured by its relative brain to body weight, or EQ) was the lowest among the dinosaurs.

Experts think that Riojasaurus probably traveled in herds for protection. Unlike smaller prosauropods such as Plateosaurus, Riojasaurus could not rear up on its hind legs. It would have used its huge size to protect itself from fierce carnnivores such as Saurosuchus.

An almost complete Riojasaurus skeleton was found in northwest Argentina, in La Rioja Province.

Riojasaurus was named after La Rioja Province in Argentina where it was found by José Bonaparte.