Fun Siamotyrannus Facts For Kids

Tanya Parkhi
Dec 08, 2022 By Tanya Parkhi
Originally Published on Sep 30, 2021
Edited by Monisha Kochhar
Here are some great Siamotyrannus facts which you are sure to love!
Age: 3-18
Read time: 5.6 Min

The Siamotyrannus (Siamese tyrant) was a genus of medium-sized theropod which roamed the earth during the Berriasian-Barremian age of the Early Cretaceous period. It was first found in Thailand in 1993 by Somchai Traimwichanon and was given its name in 1996 by Eric Buffetaut, Varavudh Suteethorn, and Haiyan Tong as the Siamotyrannus isanensis.

This dinosaur was carnivorous in nature and is theorized to be an early ancestor of the famous Tyrannosaurus rex as it shared quite a few characteristics.

Its name given by Buffetaut is similar as well, incorporating Siam (the old name for Thailand) along with Tyrannosaur. However, it was not as large, being medium-sized in length.

To learn more about this roar-some reptile, read on! For more relatable content, check out these Sanjuansaurus facts and Plateosaurus facts for kids.

Siamotyrannus Interesting Facts

How do you pronounce 'Siamotyrannus'?

Siamotyrannus is pronounced as 'sy-am-o-ty-ran-nuss'.

What type of dinosaur was a Siamotyrannus?

The Siam tyrant was a genus of metriacanthosaurid theropod dinosaur, meaning it had hollow bones and three toes on each foot. Metriacanthosaurid meant moderately spined lizard, pointing to the medium size of this dinosaur.

In which geological period did the Siamotyrannus roam the Earth?

The Siamotyrannus roamed the Earth around the early Cretaceous period, which lasted from around 100-145 million years ago.

When did the Siamotyrannus become extinct?

The Siamotyrannus most likely became extinct around 100 million years ago.

Where did a Siamotyrannus live?

The Siam tyrant dinosaur lived on what is now the continent of Asia, in and around Thailand.

What was a Siamotyrannus' habitat?

The remains of this dinosaur genus were found on the Khorat Plateau; hence we can assume that this dinosaur preferred to live among the plains.

Who did a Siamotyrannus live with?

Dinosaurs mostly lived in packs. There are high chances of similar species dinosaurs living and feeding together in groups, and this theory has been developed due to the discovery of a number of fossilized trackways containing a sequence of dinosaur footprints, all suggesting the presence of dinosaurs traveling in groups.

How long did a Siamotyrannus live?

Though the exact lifespan of a dinosaur cannot be determined, it has been estimated that they lived quite long lives, akin to those of similar reptiles like crocodiles and turtles. Due to their slow metabolisms and herbivorous diets, these beasts have been estimated to live between 80-300 years. The lifespan of this carnivore most likely fits in this range.

How did they reproduce?

Siamotyrannus dinosaurs were oviparous and reproduced by laying eggs. Their mating process was mostly similar to that of modern-day reptiles, with internal fertilization taking place inside the female's body.

Siamotyrannus Fun Facts

What did a Siamotyrannus look like?

The Siamotyrannus was a medium theropod, meaning that it had hollow bones and three toes on each foot. Its features were a long, slender body with a thick, tapering tail.

It had a large head with a short neck and powerful jaws to rip apart its prey. It was bipedal in nature, with its hind legs being stronger and thicker in order to support its weight. Its forelimbs were short and thinner and mostly used in order to grab things.

An illustration of what a typical medium-sized theropod looked like, which is likely very similar to how the Siamotyrannus dinosaur looked like
We've been unable to source an image of Siamotyrannus and have used an image of a Tyrannosaurus rex instead. If you are able to provide us with a royalty-free image of Siamotyrannus, we would be happy to credit you. Please contact us at


How many bones did a Siamotyrannus have?

Though the exact number of bones this theropod carnivore genus found had has not been determined, partial Siamotyrannus skeletons have been unearthed. The number of bones possessed by the average dinosaur has been worked out to be around 200; hence the Siamotyrannus dinosaur most probably had around 200 bones.

How did they communicate?

Dinosaurs are known for their loud, earth-shaking roars, which is mostly how this dinosaur communicated. They mostly used bellowing roars, grunts of low rumbling noises to communicate in order to mate or chase away other dinosaurs from their territories. Visual displays were also probably used, with raising of the front legs, stomping, and tail whipping involved.

How big was a Siamotyrannus?

The Siamotyrannus was a medium-sized dinosaur, estimated to measure between 20-33 ft (6.1-10.1 m) in length.

How fast could a Siamotyrannus move?

Though the exact speed of the Siamese tyrant has not been estimated, we do know that medium-sized theropods have been thought to run at an average speed of 27 mph (43.5 kph).

How much did a Siamotyrannus weigh?

The Siamotyrannus weight has been estimated to be between the range of 1102.3-3858.1 lb (500-1750 kg).

What were the male and female names of the species?

A male dinosaur has been termed a saurus whereas the female dinosaur is known as saura. We do not make any distinction in sex while referring to dinosaurs, though.

What would you call a baby Siamotyrannus?

Baby Siamotyrannus dinosaurs hatched out of eggs and were hence known as hatchlings.

What did they eat?

Being a carnivore in nature, dinosaurs of the Siam tyrant genus most likely hunted down and ate smaller dinosaurs, other terrestrial creatures, eggs, and fish.

How aggressive were they?

Due to their carnivorous natures, these theropod dinosaurs were probably quite aggressive. They would have had to hunt and chase their prey down, which would have involved baring their sharp teeth and baring their claws.

Despite being predators, there is a high chance that they were still hunted down by predatory dinosaurs of larger size such as velociraptors, which meant that they had to stay on their guard and be aggressive towards any probable intruders on their territory.

Did you know...

The name Siamotyrannus means 'Siamese tyrant' or 'Siam tyrant,' and was named in 1996 by Eric Buffetaut, Varavudh Suteethorn, and Haiyan Tong as the Siamotyrannus isanensis species.

Siam is the old name for Thailand, which is what this reptile has been named after.

This medium carnivore is thought to halfway evolved into a tyrannosaurus rex, being one of its ancestors. Many of its features reference those of the T-Rex, and the theory that tyrannosaurs originated in Asia were supported when the Siamotyrannus was found.

Siamosaurus vs Siamotyrannus - the name Simosaurus means Siamese reptile, and it was found in Thailand as well. However, rather than a tyrannosaur, it was a spinosaurus, bearing a number of spines features or humps on its back, which were absent in the Siamotyrannus. The Siamosaurus features a much larger length, measuring around 17-30 ft (5.1-9.1 m).

Is the Siamotyrannus a Tyrannosaur?

Though the Siamotyrannus belongs to the same family as the Tyrannosaurus rex, it is not quite as evolved as the latter carnivore, being placed between allosaurs and tyrannosaurs in terms of evolutionary characteristics. It was also medium in length features, which was marginally smaller than the Tyrannosaurus rex.

When was the Siamotyrannus discovered?

The Siamotyrannus skeleton was first discovered in 1993 by Somchai Traimwichanon in Phu Wiang 9 site in Khon Kaen, in Thailand. It was given the name Siamotyrannus isanensis in 1996 by Eric Buffetaut, Varavudh Suteethorn, and Haiyan Tong.

Here at Kidadl, we have carefully created lots of interesting family-friendly dinosaur facts for everyone to discover! Learn more about some other creatures from our Pedopenna facts, or Claosaurus facts for kids.

You can even occupy yourself at home by coloring in one of our free printable Siamotyrannus coloring pages.

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Written by Tanya Parkhi

Bachelor of Arts specializing in Economics

Tanya Parkhi picture

Tanya ParkhiBachelor of Arts specializing in Economics

Tanya is a skilled content creator with a passion for writing and a love for exploring new cultures. With a degree in Economics from Fergusson College, Pune, India, Tanya worked on her writing skills by contributing to various editorials and publications. She has experience writing blogs, articles, and essays, covering a range of topics. Tanya's writing reflects her interest in travel and exploring local traditions. Her articles showcase her ability to engage readers and keep them interested.

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