The fast and cunning dinosaur


Name: Abrictosaurus

Diet: Omnivorous

Weight: 30 kg

Period: Lower Jurassic

Found In: South Africa

The genus Abrictosaurus consists of a group of dinosaurs belonging to the ornitisquios, being one of the first dinosaurs that appeared on the planet, dated from the Triassic (early Mesozoic Era). Its name means “very awake reptile” because of its physiognomy it has been assumed that it was a fast and cunning animal.

The Abrictosaurus was a small animal that was found in South Africa today, and due to different paleontological studies at that time the climate was similar to the current one in that there was a wet and dry season, and they were able to make great migrations in search of food as the wildebeests do today.

This dinosaur was christened the’Waking Reptile’ because of its sharp and perceptive behavior and the fact that this Abrictosaurus had a habit’ of carrying out estivations during certain times of the year. We will discuss this in more detail later.

Abrictosaurus taxonomy

  • Abrictosaurus belonged to the Animalian Kingdom.
  • The Abrictosaurus was within the Ridge or the Chordata Division.
  • His class was Sauropsida.
  • The super-order of Abrictosaurus was Dinosauria, the Order was Ornithischia, the suborder: Neornithischia.
  • Abrictosaurus belongs to the family known as Heterodontosauridae.

Where did Abrictosaurus live?

Abrictosaurus generally lived within what is now the present Kingdom of Lesotho, which is politically included within South Africa‘s own country. The word Lesotho (or Lesotho) has a curious meaning: “the country of the people who speak the language of the Sesotho”.

In addition, this kingdom is considered an official member of the Commonwealth of Nations.

When did Abrictosaurus live?

Abrictosaurus, as we have already mentioned, played its role on Earth 200-190 million years ago, precisely at the beginning of the period known as the “Lower Triassic“.

In addition, several scientists with very prestigious trajectories affirm with certainty that this dinosaur survived between the ages known as Hettangiense and Sinemuriense.

Let us bear in mind that the Hettangiense is nothing less than a precise division in the geological time scale, this age is actually the first of the Lower Jurassic period, and it is the one preceding the Sinemurian, which is the second age of the same period, within the geological timescale.

Who discovered Abrictosaurus?

This dinosaur, named Abrictosaurus, was discovered by a famous paleontologist named Richard Thulborn in 1974.

The first time this specimen was actually known was because of the mysterious fossils of only two individuals, one of whom was found in Qacha’s Nek, a district within Lesotho.

The second individual was found in a place better known as the “Cape Province”, even within South Africa’s own country.

It should also be noted that both fossils were cataloged as part of the Elliot Superior Formation, which is precisely a geological formation that took place over time 200 million years ago and belongs to the Stormberg Group.

The Elliot Superior Formation is simply a formation that is composed mainly of sand dunes, as well as being rarely found in some swamps, and is specifically located in a not so arid area where rainfall appears only for periods, becoming very scarce.

There are also other dinosaurs that have been discovered in the Elliot Superior Formation, such as the Megapnosaurus (about 3 meters long), the Massospondylus (better known as the “extended vertebra”), the Heterodontosaurus (about 1.30 meters long) and the Lycorhinus (only 1 meter long).

If we want to see Abrictosaurus live we will have to visit University College, located in the city of London, England because the two individuals are there.

The Abrictosaurus dinosaur was originally named Lycorhinus in 1974 by its own discoverer, Richard Thulborn. But later the mistake was corrected by James Hopson (former professor at the University of Chicago), thanks to the discovery of a skull with more complete pieces.

Abrictosaurus characteristics

This specimen was only one meter long, even up to one meter in length with twenty centimeters. The maximum width it could reach was 40 centimeters and its weight was usually around 25-30 kilograms.


His arms were characterized by being not so long, a different quality from his tail, which was quite long. On the other hand, its beak had the peculiarity of being horny, that is, a beak similar to that of birds.

This dinosaur had no problem walking on all fours, as it usually did so when it was quite tired or comfortable, however, most of the time the Abrictosaurus preferred to walk on only two legs, but was not completely bipedal.

This was because their front legs were almost as long as their hind legs, and they retained various similarities, allowing this specimen to walk on both two and four legs, depending on the circumstances.

As for the toes of their legs, we can find a total of four, of which three had the characteristic of being very long, in addition to the fact that they had the shape of a claw, and the last finger was considerably shorter.

Focusing now on his head, we can see that between the upper teeth there were at least four incisors, which were always very sharp and ready for action, these dangerous incisors were quite used to pull out the vegetables, which fed the Abrictosaurus, while on the side of his jaw had flat teeth, which had the sole purpose of crushing these vegetables.

Finally, the average lifespan of this dinosaur was only 13 years, far removed from other specimens that we have already studied on this website.

The Abrictosaurus most likely had a special plumage that only covered the tail and back, this as a rather peculiar defense mechanism, which helped it look bigger against the threat of other feared predators, remember that size did matter in that prehistoric world full of large specimens.

Abrictosaurus feeding

This dinosaur usually fed on vegetables, so it was obviously a herbivore, but recent studies and research indicate that it was actually an omnivorous animal, as it may also have included meat and other elements in its diet.

Abrictosaurus behavior

There is a serious debate or discussion about the behavior of this dinosaur, and we affirm this because there is a non-small group of scientists who claim that this specimen frequently performed death avoidance estivation.


To clarify, we make a parenthesis and explain what the estivation consists of, for this task we look for a little and we find that it is nothing less than a “state of inactivity that some animals adopt to face the difficulties in the months (or years) in which there are droughts, too hot a climate or similar circumstances”.

In other words, the Abrictosaurus remained in a state of inactivity for some time, doing practically nothing, not eating, not moving, all with the sole and intelligent goal of saving energy, saving resources and waiting for a better time in which to develop his life naturally.

However, this is only a theory that so far has not been proven, but remains in the books of Paleontology because it is not crazy from any of its angles, in fact, many other animals resorted to estivation on several occasions and had greater success and fewer losses.

This stivation at times was quite effective, as it brought the animal to the point where its heartbeat was on the verge of stopping, and after the stivation, as mentioned above, they took advantage of all the vegetation typical of a less dry season.

On the other hand, it is known that this dinosaur had a body that made it easy to reach high speeds, and one of its main defense mechanisms was to run fast to escape its predators, among these predators we have the Megapnosaurus (better known as the “big and deadly lizard” and also have the Dilophosaurus (mostly known in the world of Paleontology as the “lizard of the two ridges”).

It is said that the Abrictosaurus was organized into smaller groups and that one of the members acted in cases where the predators, mentioned above, attacked.

Abrictosaurus and its resemblance to Heterodontosaurus

Because it was thought at an early stage that Abrictosaurus had not had any fangs at all, it was quite often compared to the dinosaur mentioned in the title, the Heterodontosaurus.

But after several investigations, it was concluded that Abrictosaurus had a particular way of eating or rather chewing.

Because his large jaws had the ability and ease to slide back and forth in a very tuned way, this type of repeated action was often what caused his teeth to wear much more than normal.

That is why he was confused a lot, both with Heterodontosaurus and was also confused on several occasions with Lycorhinus.

Abrictosaurus and its differences with Lycorhinus

Today we know for a fact that Abrictosaurus had much more pronounced teeth separation, even though it is said to have had far fewer crowns than originally thought, this is what makes it similar to other early ornitischids.

At first it was also presumed that Abrictosaurus had no fangs of any kind, but later on, it was found in one of the individuals found. Let’s remember that canines are actually larger canines that become very similar to the common tusks.

The characteristics of the Abrictosaurus caniniform were the following: the upper canine has an exact height of 10 and a half millimeters, on the other hand, we have the lower caniniform, which surpassed the upper one with its 17 millimeters.

The big difference between the Abrictosaurus and the Lycorhinus was precisely these caniniform since in the Abrictosaurus they were only serrated in the front part of these canines, but in the Lycorhinus the thing was going to change since they were serrated in the front and in the back surface.

Abrictosaurus in the cinema

This dinosaur Abrictosaurus appears in the film called “The Dinosaur Hunter“, which was released in 2005 and in which we can see that the scenes are developed in the future, to be more precise in 2054, the year in which the mere fact of time travel is an activity that people of that time did very often.

That is why many people traveled to “prehistory” in order to meet and hunt some dinosaurs, and among these dinosaurs, you can see some Abrictosaurus.

We recommend this film, very special for those of us who enjoy the study and knowledge of dinosaurs.