Puertasaurus

“The ribcage of a Puertosaurus was as large as a school classroom!”

Puertasaurus Facts

• A discovery of the Puertosaurus in 2001 was the first dinosaur belonging to the clade Titanosauria.
• Only one specimen in Argentina has been discovered.
• The Puertasaurus is believed to have been fairly peaceful and non-aggressive herbivores that would only fight when provoked.
• Their necks were very flexible and may have allowed them to bend over backward while eating high treetop vegetation.
• With an estimated top walking speed of 7.6 miles per hour, the Puertasaurus was one of the slowest of all dinosaurs.
• The size and shape of their vertebrae indicate they would have had the widest rib cages of any titanosaur.

Puertasaurus Scientific name

The scientific name of Puertasaurus is Puertasaurus reuili. In Latin, Puertasaurus means, “Puerta’s Reptile.” It was named in honor of Pablo Puerta, the head of the team that first discovered the creature in Patagonia in the far south of Argentina. The second half of the name, reuili, honors Santiago Reuil, Puerta’s research partner. Puertasaurus is part of the order Dinosauria and the family Saurischia.

Description & Size

The Puertasaurus was a sauropod dinosaur, meaning it walked on four legs and had a small head, long neck, and long tail. It is estimated to have been up to 98 feet long and weighed up to 55 tons. Estimating from its broad vertebrae, its rib cage would have been 16.4-26.2 feet wide. For comparison, in many modern schools, a hallway is 16 feet wide, and a classroom measures 30 by 30 feet on average. This immense size places the Puertasaurus in the class of titanosaurs along with other enormous species such as the Argentinosaurus, Supersaurus, and Dreadnoughtus. Collectively, these were the largest animals ever to walk the Earth.

Because of its huge mass, the Puertasaurus most likely moved at a slow pace, perhaps reaching a maximum of only 7.6 miles per hour. This is about half the maximum speed of a modern Komodo dragon. It would have been one of the slowest of all dinosaurs. However, as an herbivore living in densely forested habitat, it would not have had the need to run quickly. Its size was its greatest defense against predators because it was simply too large and strong to attack. Moreover, it likely multiplied its defense by moving about in herds of its own kind. Although it was likely not an aggressive species, if attacked, it could use its size, long neck, tail, and massive legs to strike out and defend itself with brute force.

Puertasaurus Evolution and History

The evolution of the Puertasaurus begins with the evolution of sauropods — the larger classification to which these dinosaurs belong. Sauropods were a group of large, quadrupedal dinosaurs that lived during the Jurassic and Cretaceous periods.

During the Early Jurassic period, around 200 million years ago, the first true sauropods appeared. These animals were much larger and had longer necks and tails than their ancestors. They also had small heads and large, barrel-shaped bodies. These early sauropods were still relatively small, but over the next few million years, they continued to evolve and grow larger. In the Middle Jurassic period, around 170 million years ago, sauropods reached their peak in size and diversity. The most famous sauropods, such as the Diplodocus and Apatosaurus, lived during this time.

During the Late Jurassic and Early Cretaceous, sauropods continued to diversify and adapt to different environments. Some sauropods, such as Brachiosaurus, had longer forelimbs than hind limbs, which allowed them to reach high branches and leaves in trees. Other sauropods had long, whip-like tails they may have used as defensive weapons.

Puertasaurus evolved in the Late Cretaceous period and, along with similar titanosaurs, represents the culmination of this line of evolution. They went extinct around 65 million years ago in the mass extinction event at the end of the Cretaceous period that brought the era of the dinosaurs to an end.

Diet – What Did the Puertasaurus Eat?

As an herbivore, Puertasaurus would have eaten all sorts of vegetation, including leaves, grasses, conifers, and cycads. Their enormously long necks and the possibility of standing on their hind legs would have given them access to the highest treetops that many other herbivores could not reach. In addition, the shape and placement of their vertebrae indicate their necks were more flexible than most other sauropods. They would have had an advantage in bending and stretching to reach the most remote tidbits of greenery. All vegetation, from the forest floor all the way up to the highest treetops, would have been in range for this dinosaur.

Herds of them likely stood in the same place for a long time, systematically devouring everything they could reach before moving on, leaving a destructive trail of deforestation behind them. In the rainy, humid climate of their habitat, the forest would have regrown quickly, but that process would have generated a lot of lower, tender new shoots of vegetation in the newly cleared land smaller herbivores could eat.

Habitat – When and Where Puertasaurus Lived

Puertasaurus lived during the Late Cretaceous, 83.6-66 million years ago in what today is Patagonia in the southern region of Argentina. Based on discoveries of fossilized vegetable matter, researchers believe the climate at that time was rainy and humid, and that part of the world would have been cloaked in a dense forest. This would have provided a nearly endless supply of food, even for animals as big as the Puertasaurus. In fact, in the same geologic formation where the Puertasaurus was discovered, researchers found other titanosaurs like Dreadnoughtus. This shows the environment was clearly able to sustain multiple enormous herbivorous species.

Threats and Predators

The Puertasaurus was so mind-bogglingly huge it is doubtful any predator would have attempted to take on an adult in a fight. In general, paleontologists believe large herbivorous sauropods like this were placid, cow-like creatures that spent most of their days moving slowly through forests and munching on trees to sustain their massive dietary requirements. However, even the largest species have eggs and young that could be easy pickings for predators, as would an adult Puertasaurus that was elderly, sick, or injured.

One predator that would have been better equipped than most for this risky venture was the Orkoraptor. This was a medium-sized theropod of up to 30 feet long that weighed up to 1.5 tons. This species lived in the same general time and place as the Puertasaurus and had specialized teeth for ripping and tearing flesh.

The Puertasaurus was not without defense against predatory attacks. It could swing its neck and tail like a club or lift up on its back legs to stomp with its forelimbs in a way that would have shaken the ground for some distance and dealt a fatal blow to anything in the way. The Puertosaurus may have also simply used its massive bulk to block and shove away anything that tried to attack its young.

We don’t know much about the animal’s social behavior, but if, as researchers believe, they moved in herds as many modern herbivores do, taking them on would have been like fighting an entire mountain range. Most predators probably moved on to easier pickings.

Discoveries and Fossils – Where Puertasaurus was Found

Only a single specimen of Puertasaurus has been found, consisting of four excellently preserved vertebrae. The discovery was made by Pablo Puerta and Santiago Reuil in 2001 in the Santa Cruz province of Patagonia, Argentina. In 2005, Fernando Novas and his colleagues described the species and named it after Puerta and Reuil.

Extinction – When Did the Puertasaurus Die Out?

The Puertasaurus went extinct along with most other species of dinosaurs at the end of the Cretaceous period. At the time, they were the most successful animals on the planet, inhabiting every continent, including Antarctica. Some studies show that during this time, dinosaurs were already beginning to go extinct and lose diversity before the asteroid hit the Earth in Mexico’s Yucatan Peninsula about 66 million years ago. This event created a global catastrophe as a result of a huge amount of debris being thrown into the atmosphere and cooling the planet drastically for a long time.

Being mostly adapted to tropical and subtropical climates, dinosaurs could not adjust to the drop in temperature or the loss of food sources as plants died off in those cold and dark conditions. It is thought that smaller omnivorous and carnivorous terrestrial animals like mammals, lizards, or birds may have been able to survive by feeding on the bodies of dead dinosaurs, roots, and dying plant matter. This allowed them to emerge as dominant species after the crisis passed.

Similar Animals to the Puertasaurus

• Argentinosaurs are a type of dinosaur referred to as titanosaurs because of their gigantic size. They were relatively slow creatures that had a speed of only five miles per hour.
• The Sauroposeidon lived in Texas, Oklahoma, and Wyoming during the Early Cretaceous period. When it was first discovered, people believed it was the largest dinosaur of all time.
• The Maraapunisaurus may be one of the world’s largest dinosaurs, but the one fossil that was ever discovered has unfortunately been lost.

Related Animals

• Xenoposeidon
• Diplodocus
• Barosaurus