Amargasaurus was a dicraeosauridae dinosaur which lived in the Early Cretaceous in South America. It had the typical dicraeosauridae build, but what really made Amargasaurus stand out from the crowd was its enlongated neck vertebrae, which were thought to be covered with skin to make a kind of frill. Whether this was used in courtship or defense remains a mystery. Amargasaurus was a herbivore.
It was small for a sauropod, only 10 metres long, and lived in the Early Cretaceous, 130 - 125 million years ago.
It was often preyed on by Giganotosaurus.