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Nowadays dinosaurs are an integral part of pop culture. They are known to the general public, children are often fans of them, they are present in many works of fiction and museums in their honor are quite numerous.

But do you really know all the dinosaurs? It is easy to mention the Tyrannosaurus Rex, the Velociraptor, the Brachiosaurus or the Triceratops, globally all the dinosaurs present in the Jurassic Park saga, as well as the Apatosaurus thanks to Arlo The Good Dinosaur. But there are many dinosaurs, small, big, dangerous or peaceful, with scales or feathers. Some of them are really weird creatures.

Today we are going to introduce you to 10 dinosaurs less known to the general public but no less interesting and particularly strange.


This is our top 10 of the weirdest dinosaurs in the Mesozoic era.


 1) Chilesaurus


Chilesaurus Diegosuarezi is "one of the weirdest dinosaurs ever discovered" according to paleontologists. It was herbivorous and could grow up to about ten feet long ( 3meters ). It lived in the geological Jurassic period, about 145 million years ago, more specifically in the Tithonian. The fossil was found in the Toqui Formation near Aysén, a region of southern Chile that is part of Patagonia.

This dinosaur belongs to the theropod family, which includes the famous carnivores Velociraptor, Carnotaurus, and Tyrannosaurus. But the anatomy of Chilesaurus presents some unusual characteristics. According to Bernardino Rivadavia, a paleontologist at the Museum of Natural Sciences in Buenos Aires, Argentina, "Its pelvic girdle resembles that of ornithischiens [...] and its hind legs - wide and four-toed - are much more similar to primitive sauropodomorphs" than those of the thinner, three-toed theropods. The relatively small skull of Chilesaurus, the shape of its beak, and its leaf-shaped teeth show that it was a plant-eater.

The fossil of this dinosaur was accidentally discovered by Diego Suarez, a seven-year-old boy who accompanied his geologist parents to the Andes in 2004. Following this initial discovery, a dozen specimens were collected, including four complete skeletons. This dinosaur clearly shows the principle of convergent evolution. That is to say the presence in several animal species of similar characters, which were not inherited from a common ancestor, but which result from the same adaptation to a type of environment.

According to paleontologist Martin Ezcurra, Chilesaurus diegosuarezi "is one of the most interesting cases of convergent evolution documented in the history of life".


  • Meaning: Found in Chile
  • Height: 3.2m long (10.5ft) 
  • Weight: Unknown
  • Group: Theropoda
  • Family: Tetanurae
  • Period: Late Jurassic (140ma)
  • Diet: Plant-Eater
  • Distribution: Chile


2) Hesperonychus


When we think of dinosaurs we often think of large and imposing animals. But there are also small dinosaurs, even tiny ones. Hesperonychus is one of them. A mini-dinosaur. The discovery of this dwarf cousin of the velociraptor, about half the size of today's cat, Hesperonychus elizabethae, reveals the diversity of prehistoric animals.

This small carnivorous predator weighed about 1-2kg for a maximum height of 50cm lived in the Upper Cretaceous period, about 80 million years ago. To help you visualize it imagined a mixture between a chicken and a velociraptor. A small bipedal animal covered with feathers with claws and teeth sharp as razor blades. Of course, it did not hunt the same prey as its theropod congeners. Nevertheless, it was most probably a fierce and dangerous small predator for animals of its size. According to its weight and skeleton, we can consider that it was a fine sprinter, it must have been fast enough to hunt small animals and insects that lived in its habitat. His jaws were filled with many small teeth that would help him to break the shells of insects and the bones of small animals. 


  • Meaning: Western claw
  • Height: 50cm long   
  • Weight: 1-2kg
  • Group: Theropoda
  • Family: Dramaeosauridae
  • Period: Late Cretaceous (76ma)
  • Diet: Carnivore
  • Distribution: North America




The archaeopteryx was a 50 to 60 cm long dinosaur weighing 0.8 to 1 kg, which lived 161 to 145 million years ago in the Upper Jurassic.

Its body was partially covered with black feathers, some of which, the remiges, were asymmetrical like those of present-day birds. It is assumed that this theropod could fly with its wings or at least glide. Thus, for nearly 150 years it was considered one of the very first birds, which meant that it belonged to the avian lineage.

However, it seems that it is indeed a dinosaur and that it could fly!

In order to be sure of the color of the feathers, paleontologists have compared the melanosomes of the Archaeopteryx with those of 87 species of modern birds, classified into four types of feathers: black, grey, brown and those characteristic of penguins. Professor Ryan Carney says, "We found that the feather was black with 95 percent certainty." According to this scientist, these melanosomes give greater strength and resistance to the feathers of modern birds. This could prove that Archaeopteryx was a flying dinosaur. The black color of this animal's feathers could also be used to regulate its temperature by protecting it from the sun, for camouflage, or, on the contrary, as a signal to recognize each other between individuals of the same species or for reproduction.


  • Meaning: Old wing
  • Height: 0.5 m (1ft 8in)   
  • Weight: 1kg
  • Group: Theropoda
  • Family: Archaeopteryhidae
  • Period: Late Jurassic (150ma)
  • Diet: Carnivore
  • Distribution: Europe




"A crocodile's head on a T-rex body."

Suchomimus ("crocodile mimic") is a large dinosaur of the family Spinosauridae with a jaw comparable to that of a crocodile that lived between 110 and 120 million years ago, in the mid-Cretaceous period in Africa.

Unlike most giant theropods, Suchomimus had very long, narrow jaws with about 100 teeth, relatively unpointed and curved backward. The animal is reminiscent of crocodilians feeding mainly on fish, such as the Gavial of the Ganges. At the time the Sahara was a hot and humid swamp, and Suchomimus may have had a dorsal sail, although not as large as that of the Dinosaur. A detailed study shows that the specimen discovered was that of a young adult, 11 meters long, and some scientists believe that it could have reached the size of the Tyrannosaurus, 12 meters long.

Suchomimus has been classified as a spinosaurus because it is very similar to the Baryonyx although larger, suggesting by some paleontologists that Baryonyx is a juvenile form of Suchomimus.


  • Meaning: crocodile mimic
  • Height:  9-11m  
  • Weight: Around 2.5tons
  • Group: Theropoda
  • Family: Spinosauridae
  • Period: Early Cretaceous ( 125ma ) 
  • Diet: Carnivore
  • Distribution: Africa




Nothronychus is a very peculiar dinosaur, quite weird, let's face it. It looks like a cross between a sloth, a giraffe, and a dinosaur. And probably covered in feathers. A curious looking.

This very strange herbivore is descended from carnivorous dinosaurs that evolved into herbivores. It's closely related to Therizinosaurus, a larger Asian relative. Nothronychus may have been feathered because other dinosaurs of its family have been found with protoplumes in their fossils. Thanks to this dinosaur, we can better imagine what life was like in mid-Cretaceous North America, a period for which very few fossils have been discovered.

Although the claws of the Therizinosauridae were long, they were not very curved. One theory is that these claws were used to bring leaves back to their mouths, but that they also served as defensive weapons. Therizinosaurs had a fairly long neck, small heads, and teeth that were used to eat plants.


  • Meaning: Claws like the sloth
  • Height: 6 meters long, 3 meters high
  • Weight: 900 kg
  • Group: Segnosaurs
  • Family: Therizinosaurids
  • Period: Upper Cretaceous (93-89 ma)
  • Diet: Herbivore
  • Distribution: United States (New Mexico)


6)Corythoraptor Jacobsi

Corythoraptor Jacobsi

A new dinosaur, a close cousin of the raptor, has been discovered and described by Chinese paleontologists. Called Corythoraptor jacobsi, it probably looked like a species of ostrich dinosaur with a feathery crest, a rather weird mix.

It is a member of a famous extinct family of feathered theropod dinosaurs, this family includes raptors family such as oviraptors, velociraptors, and many other carnivores.

The fossilized remains of this dinosaur were unearthed in 2015 not far from Canton (Guangzhou), the capital of Guangdong province in southern China. Almost complete, they reveal an animal about 1.6 meters high, carved for bipedal running in the manner of modern ostriches. This one died as a young adult of at least 8 years of age during the Upper Cretaceous period, between 100 and 66 million years ago.

The animal is distinguished by the presence of a bony crest 15 cm high. Given its general appearance, it probably closely resembled the unicaronculate casoar (Casuarius unappendiculatus), a bird species that live in northern New Guinea, or the helmet casoar (Casuarius casuarius), from Australia and Indonesia. Although fearful, casoars are dangerous because their legs have a long claw that can inflict wounds comparable to those left by a dagger.


  • Meaning: Crested raptor
  • Height: 1.6 meters long (5.2ft)
  • Weight: Unknown
  • Group: Theropoda
  • Family: Oviraptoridae
  • Period: Late Cretaceous (74-70 ma)
  • Diet: Carnivore
  • Distribution: China


 7)Ambopteryx Longibrachium


Here's another weird and surprising dinosaur. This very small dinosaur of the theropods family (these carnivorous bipedal dinosaurs, the best known of which are the raptors or tyrannosaurus) measured no more than 30cm long. It had wings and probably used them to fly between trees, or rather to glide between trees, in the manner of some modern squirrels.

The Ambopteryx had amazing wings. They show that the dinosaur was already hovering before the first birds appeared. Scientists from the Chinese Academy of Sciences (Beijing) have analyzed the fossil of this specimen. This now-extinct animal was capable of gliding, which prompts us to rethink our view of the evolution of dinosaurs.

The specimen was found in Liaoning, a province of China close to North Korea, known for its many well-preserved fossils. The bones are those of a non-aviary dinosaur, i.e. one that became extinct. Why this precision? Because many dinosaur specialists believe that modern birds are avian (not extinct) dinosaurs.

The new fossil analyzed seems to confirm the idea that these wings, quite different from those of feathered birds, may be the result of a short-lived adaptation of dinosaurs to fly. Scansoriopterygidae appears to have evolved independently of other dinosaurs, such as Coelusauria. The latter were theropods (carnivorous and bipedal dinosaurs) that had links with birds. More broadly, today's birds are descended from theropods.

Ambopteryx longibrachium belongs to the family Scansoriopterygidae, a family of feathered dinosaurs that lived during the Upper Jurassic. They are among the smallest known non-avian dinosaurs.

However, scientists are finding that the state of the fossil does not allow for the reconstruction of this wing. So it seems difficult to find out what "its exact function" was. One possible hypothesis is that the wings of Ambopteryx longibrachium could have been used to help the dinosaur run on sloping terrain.


  • Meaning: Both wing
  • Height: 0.25-0-30m long (10in)
  • Weight: Unknown
  • Group: Theropoda
  • Family: Scansoriopterygidae
  • Period: Late Jurassic (163 ma)
  • Diet: Carnivore / Insectivore
  • Distribution: China




This one is a little better known than the others, but it remains quite weird. It's the most famous representative of the duck-billed dinosaur family. It can be seen in various works of fiction such as Jurassic Park or Dinotopia.

The Parasaurolophus is recognized by its long bony stem (crest), resembling a long tube curved backward from the top of the skull. (The function of this crest is a subject of debate among scientists) . And by its strange duck beak. It was a common herbivore inhabiting the earth during the Cretaceous period, it could be found in North America, As for many dinosaurs, the skeleton of Parasaurolophus is not known in its entirety. Its morphology is therefore not 100% known. Its length is estimated at around 10 m for a skull measuring between 1.60 m and 2 m long (including the crest) according to the typologies (three species of this dinosaur are recognized: P. walkeri (the type species), P. tubicen and P. cyrtocristatus) and a weight of about 3 tons. Like the other hadrosaurs, the Parasaurolophus was able to walk on its two hind legs ( to run and escape from danger) or on all fours (to look for food and feed itself for example).


  • Meaning: near crested lizard
  • Height: 10m long (31ft) 2m tall
  • Weight: 2.5 metric tons
  • Group: Ornithischia
  • Family: Hadrosauridae
  • Period: Late Cretaceous (76-73ma)
  • Diet: Herbivore
  • Distribution: North America




Here's another very surprising dinosaur, another weird mix. Somewhere between the tyrannosaurus and the ostrich, with its five-meter high, hooked beak, this Gigantoraptor, discovered in China, surprises many specialists. It deserves its presence in our ranking of the weirdest dinosaurs.

The Gigantoraptor had to run fast. But was it to flee predators or to hunt? His way of life remains enigmatic. This fearsome looking dinosaur ran on two slender two-meter-high legs, and its long neck could lift its small head with a large hooked beak to a height of almost five meters. At the back of its body, a long, heavily muscled tail was reminiscent of that of the tyrannosaurs. From beak to tip of the tail, the animal measured eight meters.

It was gamboling - or hunting - in what is now the Gobi Desert during the Upper Cretaceous, more than 70 million years ago. At the time, this area was ideal for dinosaurs, with a warm climate, lush vegetation, humidity, and many lakes.

This giant weighed 1.4 tons, 35 times more than the typical weight of its family. Paleontologists have indeed classified it with Oviraptor (the "egg thief") among the oviraptoridae, considered to be the closest dinosaurs to present-day birds. But in this family, the weight of the eggs rarely exceeded 40 kilograms. Just when it was thought that the evolution towards birds had been accompanied by a reduction in size, Gigantoraptor is now blurring the lines.

Not much is known about him. His diet, for example, remains a mystery. It has a powerful jaw like those of a carnivore, but his long neck and small head are more reminiscent of a herbivore. Its front legs, much smaller than the endless lower limbs, may have been covered with feathers, that’s a common ornament among oviraptorids.


  • Meaning: Giant seizer
  • Height: 8m long (26ft) 5m tall (16ft)
  • Weight: 1.4 metric tons
  • Group: Theropoda
  • Family: Caenagnathidae
  • Period: Late Cretaceous (96ma)
  • Diet: Probably Carnivore
  • Distribution: Asia




And here is perhaps one of the strangest of our top, the Psittacosaurus is a kind of mixture between a lizard and a parrot. Belonging to the group of Ceratopsians of which the most famous representative is the Triceratops, this small antelope-sized dinosaur was about 2m long and lived 100 million years ago in the Early Cretaceous.

Some theories claim that this strange dinosaur was able to camouflage itself, a bit like some lizards today. Probably in order to escape from predators. According to the skin analyses that have been found on many fossilized specimens it would seem that the Psittacosaurus was covered with scales with however a peculiarity of its own, it would have had a row of hair about 16cm long at the level of the spine, To this day the usefulness of these hairs are still a mystery, although the reason for thermoregulation is rejected by most scientists, no one agrees on the true usefulness of these hairs, perhaps as a means of distinguishing between limbs or sexual apparatuses.


  • Meaning: Parrot lizard
  • Height: 2m long (6.5ft) 
  • Weight: 20kg
  • Group: Ceratopsia
  • Family: Psittacosauridae
  • Period: Early Cretaceous (120-100ma)
  • Diet: Herbivore
  • Distribution: Asia

 11) Nomingia ( Bonus )


And here is the Nomingia, a small dinosaur with a strange physique once again. This small feathered dinosaur from the oviraptorid family lived in the late Upper Cretaceous in Asia, particularly in what is now the Gobi Desert in Mongolia. Its relatively average size for an oviraptorid dinosaur was estimated by Gregory Paul to be just under 2m long and weigh about 20kg. We can appreciate its peculiar physical.


This is our Top 10 of the weirdest dinosaurs of the Mesozoic time. Of course, there are many other weird dinosaurs, and probably many more that are still waiting to be discovered. This list is not exhaustive.

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