Amargasaurus, was a rather small sauropod, with a distinctly short neck. It lived in modern day Argentina around 130-125 million years ago, during the Early Cretaceous Period. Named after the La Amarga Formation in Argentina where it was found, it is an interesting species within the sauropods.

Obviously large if compared to any living animal, at 30-40 feet length and just short of ten tons, it was a small’ish sauropod. Along with the unusually short neck (for a sauropod) it also had a double set of spines along its neck and back that sets it apart from sauropods.

Amargasaurus Key Facts

Amargasaurus Origins – Taxonomy, Timeline, and Discovery

Amargasaurus cazaui, as I mentioned above, gets its name from the location where it was found, the La Amarga Formation in Argentina. The type name A. cazaui is in honor of Argentinian geologist Dr. Luis Cazau.

It belongs to the Sauropodomorpha group, specifically the Dicraeosauridae family. And so far it is the sole species in its genus. A. cazaui lived during the Early Cretaceous period, a time of significant evolutionary change with the appearance of several new dinosaur groups and the extinction of others.

The first discovery of the Amargasaurus was made in 1984 by Guillermo Rougier. The dinosaur was later described in 1985 by José Bonaparte, making it a relatively recent addition to our knowledge of dinosaur life.

Fossil Evidence

This first discovery from 1984 in the La Amarga Formation was significant, providing a nearly complete skeleton that offered a wealth of information about this unique dinosaur. Since then, additional fossils have been found in the same region, further expanding our understanding of the Amargasaurus.

The fossils discovered include vertebrae, ribs, and parts of the skull and limbs. These fossils have been well-preserved, allowing researchers to study the dinosaur’s physical characteristics in detail. Moreover, specimens include a nearly complete skeleton, which has provided valuable insights into the dinosaur’s size, shape, and locomotion.

Amargasaurus Size and Description

Amargasaurus cazaui was a medium-sized dinosaur, mking it small for a sauropod. Setting it apart from its sauropoda cousins was its shorth neck. Its most distinctive feature however was a double row of tall spines along its neck, back, and tail. These spines, which were likely covered in skin, may have been used for display or defense, demonstrating the dinosaur’s adaptability to its environment. Its long neck and tail, manner of locomotion, and herbivorous diet are typical of sauropods. Like other sauropods, the Amargasaurus moved on all four legs and had a body built for a herbivorous lifestyle.

Size and Weight of Type Species

This was a relatively small sauropod, measuring about 30 to 43 feet in length. Despite its smaller size compared to other sauropods, it was still a substantial creature. Its weight is estimated to be around 9 tons. These estimates are based on the nearly complete skeleton found, which has provided valuable insights into the dinosaur’s size and weight.

The Amargasaurus in its Natural Habitat and Environment

It lived in what is now Argentina during the Early Cretaceous period. The environment during this time was likely lush and vegetated, providing ample food sources for this herbivorous dinosaur. 

As a result of being an herbivore, it likely fed on a variety of plants including ferns, cycads, and conifers. Its long neck would have allowed it to reach vegetation that other dinosaurs couldn’t. This would give it an evolutionary advantage in its environment. 

Even with its relatively small size for a sauropod, it was large enough to have had a significant impact on its environment. Its feeding habits may have shaped the vegetation in its habitat, and its physical presence would have been a notable feature of the landscape.

Contemporary Dinosaurs

Imagine the Amargasaurus coexisting with the similarly-named Amargatitanis. These two dinosaurs are also closely related, belonging to the same group called Dicraeosauridae. They likely went back-and-forth in a lifelong battle of competition over the same resources. Similarly, the Padillasaurus could have been a direct competitor for resources as another herbivorous dinosaur of similar size.

In contrast, the Ligabueino was a smaller carnivore. It might have viewed the larger Amargasaurus as a potential source of food, leading to possible predator-prey interactions. These interactions paint a vivid picture of a time when these magnificent creatures roamed the Earth, each playing a role in the intricate balance of their ecosystem and maintaining the competitive environment that encouraged adaptation and evolution.

Interesting Points about Amargasaurus

Frequently Asked Questions

Sources

Article last fact checked: Marius, 12-24-2024

Featured Image Credit: Nobu Tamura, CC BY-SA 4.0, via Wikimedia Commons