Piatnitzkysaurus: Unveiling the Secrets of a Middle Jurassic Predator

Venture back to the Middle to Late Jurassic Period, and you’ll find the Piatnitzkysaurus, a lesser-known but fascinating dinosaur. This carnivorous Theropod, discovered in the rugged terrains of Southern Argentina, offers a unique window into a world long gone. Named in honor of Alejandro Matveievich Piatnitzky, who played a pivotal role in its discovery, this dinosaur stands as a testament to the diverse and intriguing prehistoric life.

Piatnitzkysaurus Key Facts

Meaning of namePiatnitzky’s Lizard
Type SpeciesPiatnitzkysaurus floresi
When it Lived182.0 to 175.6 MYA
PeriodMiddle-Late Jurassic Period
EpochMiddle Toarcian
Length14.0 feet
HeightApproximately 5.0 feet
Weight990.0 pounds
MobilityMoved on two legs
First Discovery1977 by Jose Bonaparte
Described by1979 by Jose Bonaparte
HolotypeMACN CH 895
Location of first findCañadón Asfalto Basin, Southern Argentina

Piatnitzkysaurus Origins, Taxonomy and Timeline

This dinosaur, whose name pays homage to Alejandro Matveievich Piatnitzky, is a testament to the varied types of life that existed millions of years ago. The Greek suffix ‘sauros,’ meaning lizard or reptile, completes its name–Piatnitzky’s Lizard.

Piatnitskysaurus dinosaur
Nobu Tamura, CC BY-SA 3.0, via Wikimedia Commons

In the realm of taxonomy, Piatnitzkysaurus is classified as a Theropod, a group known for their bipedal stance and predominantly carnivorous diet. This classification places it within the Piatnitzkysaurid family. The type species, Piatnitzkysaurus floresi, is the only species in the genus.

It thrived during the Middle to Late Jurassic Period, specifically from around 182.0  to 175.6 million years ago. This epoch, known as the Middle Toarcian, was a period of significant geological and ecological changes that undoubtedly influenced the evolution and lifestyle of Piatnitzkysaurus.

Listen to Pronunciation

Check out this video for the correct pronunciation of Piatnitzkysaurus. 

Discovery & Fossil Evidence of Piatnitzkysaurus

The holotype specimen, known as PVL 4073, was unearthed during expeditions in 1977, 1982, and 1983 within the Cañadón Asfalto Formation in Argentina. These sediment layers date back approximately 179.0 to 177.0 million years ago and contained this remarkably complete specimen. This find included a partial skull and anterior postcranial skeleton of a subadult individual. It was significant for being one of the best-preserved examples of a Megalosaur, offering a rare glimpse into the anatomy of these ancient predators.

The type species was first described by Jose Bonaparte in 1979. This naming was a tribute to Alejandro Matveievich Piatnitzky, a Russian-born Argentine geologist, acknowledging his contributions to the field. Initially classified alongside well-known dinosaurs like Allosaurus and Dilophosaurus, Piatnitzkysaurus’s classification journey has been dynamic, reflecting the evolving nature of paleontological understanding. Over time, it has been reclassified variously as an Abelisaurid, a basal Carnosaur, and a non-Megalosaurid Megalosauroid, before finally being placed in its own family Piatnitzkysauridae in 2012.

The fossil record, though limited, is quite informative. In total, two partial skeletons have been identified. These included a fractured skull and parts of two postcranial skeletons. These remains collectively make Piatnitzkysaurus the most completely known Theropod from the Middle-Late Jurassic Period in the Southern Hemisphere. Each bone and fragment adds to the story of this dinosaur and pieces together a life that once thrived millions of years ago.

Piatnitzkysaurus Size and Description

Embarking on a journey to understand the physical stature of Piatnitzkysaurus, we find a dinosaur that was both agile and robust–a combination that made it a formidable predator of its time.

Size and Weight of Type Species

Piatnitzkysaurus floresi reconstruction based on PVL 4073.
Paleocolour, CC BY-SA 4.0, via Wikimedia Commons

The holotype of Piatnitzkysaurus is a subadult but still provides crucial clues about its size. This dinosaur measured approximately 14.0  feet in length and weighed around 990.0 pounds. These estimates, while specific to the subadult holotype, give us a glimpse into the physical presence of this Jurassic predator. 

The Dinosaur in Detail

With its relatively light build and medium size, this was a bipedal carnivore that combined power and agility. Its robust arms and powerful hind legs, each adorned with four toes, speak to a lifestyle of active predation. Part of its hip bones measured an impressive 16.7 inches, hinting at a strong and efficient locomotion system. Its braincase shares similarities with the Megalosaurid Piveteausaurus from France, suggesting a common thread in the evolutionary tapestry of Megalosauroids.

A comparison with the well-known Allosaurus reveals both similarities and key differences. While there is a general resemblance, Piatnitzkysaurus’s shoulder blade was shorter and wider. This trait is more primitive among Theropods. This dinosaur’s humerus was about half the length of its femur, another characteristic of basal Theropods. Interestingly, the forelimbs of Piatnitzkysaurus were proportionally longer than those of Allosaurus and the wide contact between the pubis and ischium was quite distinct from more derived theropods. The pubis itself further differentiates Piatnitzkysaurus from Allosaurus.

The comparison with its sister taxa, Condorraptor, raises interesting questions about individual variation within the species. These two taxa are similar and differ mainly in sacral vertebrae and tibias. This aspect of its anatomy not only informs us about Piatnitzkysaurus itself but also about the diversity and complexity of theropod evolution during the Jurassic Period.

Interesting Points about Piatnitzkysaurus

Piatnitzkysaurus in its Natural Habitat

The environment this carnivore inhabited was likely diverse, with a climate and geography that supported a range of vegetation types. This setting provided the backdrop for the life and survival strategies of Piatnitzkysaurus and other South American dinosaurs.

As a carnivore, it was an integral part of the food chain. Its diet would have consisted of other contemporary creatures and its role as a predator would have influenced the dynamics of its ecosystem. The locomotion, primarily on two legs, suggests a lifestyle that included active hunting and possibly scavenging.

Whether it was a solitary hunter or part of a larger group remains a subject of speculation. However, its interactions with other species, both as predator and competitor, would have been a key aspect of its existence. Its senses were adapted for hunting and survival and would have been finely tuned to its environment, making it a formidable presence in its natural habitat.

Contemporary Dinosaurs

In the prehistoric landscapes where Piatnitzkysaurus roamed, a dance of survival played out daily. This agile predator was roughly the size of a modern-day horse. It often found itself in a tense ballet with Patagosaurus, a behemoth that dwarfed it in size. Imagine Piatnitzkysaurus, with its keen eyes and swift legs, weaving through the ancient ferns and cycads. Its life was a constant quest for sustenance that often brought it into the grazing territories of the massive, long-necked Patagosaurus. These gentle giants munched on the high canopies and were like moving mountains compared to the lithe Piatnitzkysaurus. Yet, despite their size difference, there was a mutual respect–a silent understanding that each played a role in the delicate balance of their shared world.

Now, enter Condorraptor, a contemporary and potential rival of Piatnitzkysaurus, roughly the same size but with a demeanor as fierce as its name suggests. Picture the tension in the air when these two predators crossed paths. A rustle in the underbrush, a flash of teeth, and a swift retreat–such encounters were common. While Piatnitzkysaurus was not typically the hunted, it had to be wary of Condorraptor when competing for prey or territory. These interactions were charged with the raw energy of survival, painting a vivid picture of the dynamics at play in this ancient ecosystem. Piatnitzkysaurus, with its own set of skills and instincts, navigated this world of giants and rivals and carved out its own place in the annals of prehistoric life.

Frequently Asked Questions

What period did it live in?

This dinosaur lived during the Middle to Late Jurassic Period, approximately 182.0 to 175.6 million years ago.

Where was this dinosaur first discovered?

It was first discovered in the Cañadón Asfalto Basin in Southern Argentina.

What type of diet did it have?

It was a carnivore, feeding on other animals in its ecosystem.

How did this dinosaur move?

It moved on two legs like many of its Theropod relatives.

Who first described this dinosaur?

Jose Bonaparte first described Piatnitzkysaurus in 1979.

What does its name mean?

The name Piatnitzkysaurus means “Piatnitzky’s Lizard,” honoring Alejandro Matveievich Piatnitzky.


The information in this article is based on various sources, drawing on scientific research, fossil evidence, and expert analysis. The aim is to provide a comprehensive and accurate overview of Piatnitzkysaurus. However, please be aware that our understanding of dinosaurs and their world is constantly evolving as new discoveries are made.

This article was last fact checked:Joey Arboleda, 12-09-2023

Featured Image Credit: Paleocolour, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons