The Therizinosaurus is part of a group of large dinosaurs belonging to the Therizinosauridae family. These specimens roamed on the surface of the Earth about 70 million years ago, during the Late Cretaceous era. This lizard is also called the scythe lizard.
Only a single type species comes under this dinosaur genus, the Therizinosaurus cheloniformis.
The discovery of the first fossil remains of the Therizinosaurus was made in the year 1948. It was found in China, at the Gobi Desert during a field expedition of a Mongolian team. The species was later described in the year 1954 by Soviet paleontologist Evgeny Maleev.
The knowledge of this genus comes from the presence of a few bones alone. These include large manual unguals (claw bones). Additional information came from other fore and hindlimb elements that were discovered between the 1960s to the 1980s.
The most catchy feature is huge claws of Therizinosaurus. Earlier, fossil skeletal remains of this Therizinosaur were thought to belong to a huge turtle-like reptile. This huge dinosaur weighed about 6,613.9 lb (3,000 kg)! Imagine how huge these Therizinosaurs were!
The Therizinosaurus pronunciation goes as 'Ther-ih-zine-oh-sore-us'.
The Therizinosaur is an extinct genus of dinosaurs that were Therizinosaurids.
The existence of this Theropod dinosaur was roughly 70 million years ago, in the Late Cretaceous period.
Despite knowing a lot about this Theropod with long claws, we do not know when exactly this dinosaur became extinct.
These dinosaurs were said to live in present-day Asia, in the Nemegt formation, all the way back during the Late Cretaceous period.
We do not have any information about the habitat of this dinosaur.
We do not know who these dinosaurs lived with as there is not much research available on whether these dinosaurs with claws were solitary or lived in groups.
Despite having a lot of information on this Theropod, we are not aware of the lifespan of the Therizinosaurus.
Unfortunately, there is not much known on the reproductive history of Therizinosaurs.
Unfortunately, the complete Therizinosaurus skeleton has not been found.
The Therizinosaurus skull was small in proportion to its body, according to assumed reconstructions. This large skull had a long neck, with a horny beak (rhamphotheca) as well as a wide torso, which was required to better process food.
Forelimbs of this herbivore were well advanced, having three fingers each. These fingers bore unguals (sharp claws) that were elongated, stiff, and had curvatures at the tips. This dinosaur genus is known to have the longest manual unguals of all the land animals, reaching up to more than 1.6 ft (50 cm) in length.
Hind legs had four weight-bearing toes. These toes are different from other known Theropod dinosaurs, with the first toe being slightly reduced to a dewclaw. This resembles toe structures of Sauropodomorphs, unlike their relatives, Theropods.
Legs were strong and robust, helping these animals balance and making them capable to move efficiently.
As the discovery of the entire skeleton has not been made, from existing fossil remains we are unaware of the total number of bones in this specimen.
We do not know how these Therizinosaurs communicated exactly. Most dinosaurs are believed to have used grunts and bellows to communicate.
This colossal Therizinosaur had a total length of about 29.5-32.8 ft (9-10 m). This is about nine times the length of the Parvicursor remotus, which existed about 72 million years ago.
Due to its large body structure and body mass, we can conclude that Therizinosaurs were slow-moving.
It has been estimated that the Therizinosaurus had a body weight of about 6,613.9 lb (3,000 kg). Extremely massive, isn’t it?
A female dinosaur of this genus can be called a Therizinosaura, while a male dinosaur can be referred to as a Therizinosaurus.
There is no specific name for a baby Therizinosaurus. You can call it a hatchling.
It has been discovered that this dinosaur was a herbivore. The diet probably consisted of leaves, shrubs, and herbs. Baby dinosaurs also ate plants and berries. This animal was not a predator and spent its life eating plant material.
The possible dinosaur which would have been on the list of predators for these long-clawed scythe dinosaurs includes the Tarbosaurus.
We do not know how aggressive the scythe lizard was.
There is no direct evidence on this, but Therizinosaurus feathers may have existed, given their place in the family tree of Theropods and their lifestyle. There may have been some period when these Therizinosaurs were covered in feathers on their arms.
Some members of the Therizinosauroidea superfamily, such as the Beipiaosaurus, were said to have layers of feathers. These feathers did not help them fly but instead kept them warm. This specimen was also herbivorous, and not a dangerous predator.
The generic name of this dinosaur, Therizinosaurus, is derived from the Greek term ‘θερίζω’ (therizo) which translates to cut, scythe, or reap. ‘Σαῦρος’ or ‘sauros’ is a Greek word that translates to ‘lizard’. This name is given in reference to giant claws possessed by the dinosaur.
The specific name, cheloniformis, comes from the combination of the Greek word 'χελώνη' (chelóni), meaning ‘turtle’, and Latin term ‘formis’. This name was assigned as the Therizinosaurus fossil was earlier assumed by the paleontologist to have belonged to a turtle-like reptile.
Russian paleontologist Evgeny Maleev declared a separate family for the new taxon, Therizinosauridae. At the time of the original description, much information about this group was not known. Hence, Maleev assumed that the PIN 551-483 skeletal remains actually belonged to a 15 ft (4.6 m) long turtle. This turtle was thought to have used its giant claws to harvest and feed on seaweed. You can find the holotype PIN 551–483 claws at the Moscow Paleontological Museum.
The Soviet paleontologist has two dinosaurs, the Maleevus and the Maleevosaurus, named in his honor.
Much information on the history and life of this dinosaur has been written in the 'Paleontology and Biostratigraphy of Mongolia: The Joint Soviet-Mongolian Paleontological Expedition'.
The 'Paleontology and Biostratigraphy of Mongolia: The Joint Soviet-Mongolian Paleontological Expedition' has been contributed to by many scientists and researchers.
To date, scientists are yet to have discovered a complete skull of this dinosaur.
Other Mongolian origin dinosaurs include the Talarurus, the Deinocheirus, the Tsagantegia and the Achillobator.
About 17 egg clutches were discovered in the Gobi Desert. Yoshitsugu Kobayashi of Hokkaido University announced that these were actually from Therizinosaurus egg nests.
Of all animals known on the planet, the Therizinosaurus is said to have the longest claws.
Among the most attractive features which belong to fossils of these Therizinosaurs are the Therizinosaurus claws. Arms of the dinosaurs were equipped with long claws. These claws were earlier confused by scientists to have belonged to a turtle-like animal.
However, later it was clarified that it in fact belonged to this dinosaur genus. It has been suggested that these claws may have been for pulling out vegetation. The presence of these long claws has also given these Therizinosaurs an alternate name, the scythe lizard.
From fossils which belonged to this animal, it has been closely observed and has been concluded that this dinosaur actually had a herbivore diet. The Therizinosaurus claw would have been used for pulling out vegetation and tree leaves.
Here at Kidadl, we have carefully created lots of interesting family-friendly dinosaur facts for everyone to discover! Learn more about some other dinosaurs from our Austroraptor fun facts for kids and Zuniceratops interesting facts pages.
You can even occupy yourself at home by coloring in one of our free printable Therizinosaurus coloring pages.
Main image by Mariolanzas.
Second image by Woudloper.