Therizinosaurus was a theropod dinosaur that lived in Asia during the Late Cretaceous Period. Therizinosaurus is a marvel of evolution, a creature that seems to defy categorization. Its long, scythe-like claws, its herbivorous diet as a theropod, and its hulking size make it a subject of fascination and study.
With its unique features and peculiar lifestyle, this dinosaur offers a glimpse into a world that is both alien and familiar. It is a testament to the endless forms life has taken on Earth, forever evolving.
Key facts
| Keyword | Fact |
|---|---|
| Therizinosaurus pronunciation | Ther-uh-zino-sawr-us |
| Meaning of name | Scythe lizard |
| Group | Theropoda |
| Type Species | Therizinosaurus cheloniformis |
| Diet | Herbivorous |
| When it Lived | 72.1 to 66.0 MYA |
| Period | Late Cretaceous |
| Epoch | Maastrichtian |
| Length | 33.0 ft |
| Height | 20.0 ft |
| Weight | 5.0 tons |
| Mobility | Moved on two legs |
| First Discovery | 1948 by Mongolian Paleontological expeditions organized by the USSR Academy of Sciences |
| Location of first find | Mongolia |
| First Described by | 1954 by Evgeny Maleev |
| Holotype | PIN 551-1 |
Therizinosaurus Taxonomy and Timeline
Therizinosaurus, or “scythe lizard,” gets its name from its most distinctive feature: its (really) long, scythe-like claws. The name is a fitting one, capturing the unique and somewhat eerie nature of this creature. It is derived from the Greek words “therizo” meaning scythe and “sauros” meaning lizard.
Taxonomically, Therizinosaurus belongs to the group Theropoda. This group includes some of the most well-known dinosaurs, such as Tyrannosaurus Rex and Velociraptor. However, unlike its carnivorous cousins, this dinosaur was an herbivore. This unusual dietary preference has made it a subject of much study and speculation.
It lived during the Late Cretaceous period, in the Maastrichtian epoch, approximately 72.1 to 66 million years ago. This was a time of great change, as the world was transitioning from the age of dinosaurs to the age of mammals. With its unique adaptations, this dinosaur was well-suited to this changing world.
Discovery & Fossil Evidence
The first fossils were discovered in 1948 by the Mongolian Paleontological expeditions organized by the USSR Academy of Sciences. The find, made in Mongolia, was a significant one, as it shed light on a previously unknown group of dinosaurs. It was initially mistaken for a turtle-like reptile due to its unusual features, but further study revealed its true nature.
Since the initial discovery, several other fossils have been found that provide a more complete picture of this enigmatic dinosaur. These fossils include parts of the limbs, vertebrae, and the distinctive claws that give Therizinosaurus its name. The fossils are well-preserved and offer a wealth of information about the dinosaur’s physical characteristics and lifestyle.
The holotype, or the specimen that defines the species, is a set of claws and limb bones. Designated as PIN 551-1, this specimen is housed in the Paleontological Institute of the Russian Academy of Sciences. It serves as the benchmark for all subsequent discoveries, providing a reference point for paleontologists studying this fascinating creature.
Therizinosaurus Size and Description
This is a dinosaur that stands out in the fossil record, not just for its unique features but also for its size. Therizinosaurus was a large theropod, a group of dinosaurs that is almost exclusively made up of carnivores. Despite its lineage and frightening appearance, this dinosaur was an herbivore with a unique set of physical characteristics.
Its most distinctive feature was its long, scythe-like claws, which could reach lengths of up to 3.3 feet. These claws, which could reach lengths of up to 3.3 feet, are among the longest of any known animal. They were likely used for foraging and defense, allowing Therizinosaurus to reach high vegetation and fend off predators.
Being a herbivore, quite unusual in the Theropoda family, is reflected in the dinosaur’s physical characteristics, including its round belly and small head. The dinosaur’s long neck would have allowed it to reach vegetation at various heights, making it a versatile forager. It moved on two legs and its tail served as a counterbalance to its heavy front body.
The dinosaur’s skin is believed to have been covered in feathers, a trait shared with other theropods. This feather covering would have provided insulation, protecting the dinosaur from the cold. Its speed is not well known, but given its size and body shape it was likely not a fast runner.
Its adaptability is reflected in its survival during the Late Cretaceous period, a time of great change and upheaval. The dinosaur’s unique features, including its long claws and herbivorous diet, allowed it to thrive in a changing world.
Size and Weight of Type Species
Its size is a subject of ongoing research. Based on the available fossil evidence, it is estimated that this dinosaur could reach lengths of up to 33 feet and stand about 20 feet tall. However, these estimates are subject to change as more fossils are discovered and studied.
The weight is also a matter of speculation. Some estimates suggest that Therizinosaurus could weigh as much as 5 tons. However, without more complete fossil evidence, it is difficult to provide a definitive weight estimate. Despite these uncertainties, there is no doubt that Therizinosaurus was a large and imposing creature. Its size and unique features made it a formidable presence in its environment.
Therizinosaurus in its Natural Habitat
This dinosaur lived in what is now Mongolia, a region known for its diverse and rich fossil record. The Late Cretaceous period was a time of warm climate and lush vegetation. The dinosaur’s herbivorous diet suggests that it lived in areas with abundant plant life, possibly forests or woodlands. Its long neck and claws would have allowed it to reach vegetation at various heights, making it a versatile forager. The dinosaur’s large size and unique features suggest that it was a dominant presence in its environment, shaping the landscape around it.
Its social behavior is not well known but it is possible that it lived in groups or herds. This social structure would have provided protection against predators and increased the chances of finding food. The dinosaur’s long lifespan, estimated to be several decades, suggests that it was a successful and adaptable creature.
Interesting Points about Therizinosaurus
- Its long, scythe-like claws are among the longest of any known animal. These claws were likely used for foraging and defense, making the Therizinosaurus a formidable presence in its environment.
- Despite belonging to a group of almost exclusively carnivorous dinosaurs, the Therizinosaurus was a herbivore. This unusual dietary preference sets it apart from other theropods.
- It lived during the Late Cretaceous period, a time of great change and upheaval. The dinosaur’s unique adaptations allowed it to thrive in a changing world.
- It is known from relatively few fossils, making it a subject of ongoing research and study. Despite this, the dinosaur’s unique features and lifestyle make it a fascinating subject for paleontologists.
- The size and weight are a matter of ongoing speculation. Based on the available fossil evidence, it is estimated that this dinosaur could reach lengths of up to 33 feet and weigh as much as 5 tons.
Contemporary Dinosaurs
Therizinosaurus was not the only interesting dinosaur roaming Asia in the Late Cretaceous. Among these were Tarbosaurus, Saurolophus, and the iconic Tyrannosaurus. Each of these dinosaurs, distinct in their own right, contributed to the intricate dynamics of life.
The terrifying Tarbosaurus might have posed a significant threat to Therizinosaurus. Its massive jaws and sharp teeth were tools of terror capable of inflicting lethal damage. Yet, Therizinosaurus was no easy prey. Its long, clawed forelimbs could have served as a formidable defense against such predators. Saurolophus, on the other hand, was an herbivore like Therizinosaurus. They might have competed for the same plant resources, yet their different feeding heights could have allowed them to coexist without much conflict.
Tyrannosaurus, arguably the most famous of all dinosaurs, was another contemporary that shared Therizinosaurus‘ world. Its reputation as a fearsome predator might suggest a predator-prey relationship between them. However, Therizinosaurus‘ unique physical attributes, particularly its massive claws, might have deterred even the mighty Tyrannosaurus. This intricate network of relationships paints a vivid picture of the Therizinosaurus’ life, highlighting its role and resilience in a world teeming with both danger and opportunity.
List of All Dinosaurs
We have created a list of all dinosaurs we have covered here, sorted across the seven main groups of dinosaurs. We also include information about their type of diet, (omnivore, herbivore or carnivore) and the time they lived.
Frequently Asked Questions
The name translates to “scythe lizard,” a reference to the dinosaur’s long, scythe-like claws.
Despite its appearance and lineage, it was an herbivore that fed on a variety of plant matter.
This dinosaur lived during the Late Cretaceous period, around 72.1 to 66.0 million years ago.
The first fossils were discovered in Mongolia in 1948.
It could reach lengths of up to 33 feet and stand about 20 feet tall. It is estimated to have weighed as much as 5 tons.
Its long, scythe-like claws and herbivorous diet despite being a theropod make it a unique dinosaur.
Sources
Please note that 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 the Therizinosaurus, but 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, 04-06-2025