Puertasaurus

Overview

Puertasaurus reuili was a colossal titanosaur sauropod from the Late Cretaceous period in Patagonia, Argentina. Known from only a few vertebrae, Puertasaurus exhibits some of the most massive dorsal vertebrae discovered, suggesting it reached enormous lengths—potentially 95–100 ft (29–30 m)—and weighed upwards of 50–60 tons. Its remains highlight the extreme size that titanosaurian sauropods achieved in South America.

Unearthed in the Santa Cruz Province, the dinosaur was named after the landowner who helped find the fossils. While only partial remains have been recovered, Puertasaurus stands out for its exceptionally wide vertebrae, reflecting a robust trunk and an immense, broad torso. Ongoing studies compare it with other giant titanosaurs, such as Patagotitan and Argentinosaurus, to unravel evolutionary trends in the region’s megaherbivores.

Quick Facts

Diet

Herbivore (ferns, cycads, and other plant matter)

Weight

~50–60 tons (est.)

Length

~95–100 ft (~29–30 m)

Speed

~5 mph (walking pace est.)

Bite Force

~400–500 psi (estimated)

Discovery & Significance

Puertasaurus was described by Argentine paleontologist Fernando E. Novas and colleagues in 2005, based on vertebrae unearthed by a fossil-hunting team in southern Patagonia. The large dorsal and cervical vertebrae indicate a short, wide torso, distinguishing Puertasaurus from other titanosaurs. Despite limited fossils, it contributes to our understanding of how sauropods diversified and reached enormous sizes in Gondwana’s Late Cretaceous ecosystems.

Ongoing research attempts to refine Puertasaurus’s body proportions and relationships with close relatives. Comparisons to Futalognkosaurus and Patagotitan highlight both unique features, like trunk width, and shared traits that define giant titanosaurs. The remains underscore Patagonia’s role as a hotspot for some of the largest dinosaurs ever known.

Puertasaurus vs. Other Giant Titanosaurs

More Details

One might wonder how many huge titanosaurs one continent can hold. In southern Patagonia’s Cerro Fortaleza Formation, Puertasaurus reuili offers another glimpse into that world of super-sized dinosaurs. Discovered in 2001 by a pair of dedicated fossil hunters, Puertasaurus is known from only four vertebrae—yet even these scant remains paint a picture of a titanosaur that may have pushed the boundaries of size. When first announced, estimates of 35 to 40 meters in length and 80 to 100 tonnes circulated, but as more research rolled in, experts refined the length to around 30 meters and the mass to a humbler (though still impressive) 50 to 60 tonnes. Arguments occasionally crop up whether it was bigger than certain other titanosaur heavyweights, but so far, the data indicates Puertasaurus belongs among the top-tier, broad-bodied group called Lognkosauria, alongside Argentinosaurus and Patagotitan. Dramatic proof of this dinosaur’s girth lies in a single dorsal vertebra measuring 1.68 meters across—sometimes cited as the broadest known among sauropods. And the neck vertebra, while incomplete, suggests that Puertasaurus carried a formidable cervical column, enabling it to graze foliage high above the ground. That large, robust build, combined with its wing-like transverse processes on the back vertebra, tells us Puertasaurus was well-suited to supporting considerable weight, an essential adaptation for a creature that likely roamed lush floodplains and forests teeming with conifers. Geologically speaking, the Cerro Fortaleza Formation has raised some confusion regarding age, but it’s likely that Puertasaurus hailed from the Campanian–Maastrichtian stage, roughly 76 to 70 million years ago. During this era, the environment was moist, with ample vegetation. Fossil evidence of cycads, conifers, and other plants indicates a forested habitat, probably shared by predators like Orkoraptor, herbivores such as Talenkauen, and the gargantuan Dreadnoughtus. Even though Puertasaurus left only four bones behind, each vertebra is a window into a life spent traversing a fertile floodplain—another reminder of how profound the Mesozoic world truly was.

References & Further Reading