Herrerasaurus was one of the top predators of its age - surpassed only by large rauisuchians such as Saurosuchus and Prestosuchus. A recently discovered Herrerasaurus skull had puncture wounds thought to be from Saurosuchus.

Herrerasaurus' forelimbs were less than half the length of its hindlimbs but were much longer than those of T. rex

The Valley of the Moon in Argentina, where Herrerasaurus was found, is one of the world's richest Triassic fossil sites.



"Herrera's lizard"


Herrerasaurus was bipedal and carnivorous. It would have been one of the very first dinosaurs ever to walk the planet.



Herrerasaurus lived during the Late Triassic, 231 million years ago.

Extinct for about: 00,000,000,000 Days00 Hours00 Min00 Sec

How old are you?
00,00,00.00 of your lifetimes have passed since their extinction.

They Call it Home

Herrerasaurus fossils have been found in the Ischigualasto Formation of northwestern Argentina. Today this landscape is known as the 'Valley of the Moon' because of its eerie, moon-like geology. Here, palaeontologists have also found Eoraptor, another early dinosaur. 230 million years ago, the Ischigualasto landscape was a floodplain dominated by rivers and studded with volcanic activity. Today, it is an arid, barren landscape.

Rivers / Lakes

Rivers / Lakes

Flood Plains

Flood Plains

Active Volcanoes

Active Volcanoes




  • Ischigualasto Formation

What We Heard About Their Hearing

Human Ear

Nothing is known for certain about Herrerasaurus' hearing 


What Big Teeth You Have

Dinosaur Tooth

The lower jaw was lined with large, inwardly curving teeth so that Herrerasaurus could hold its prey more efficiently.


Nose Knowledge

Human Nose

We know little about Herrerasaurus' sense of smell. 


The Poop Scoop

Dinosaur Poop

We haven't found any Herrerasaurus poo. 


The Most Fantastic Find

Herrerasaurus was first discovered in 1958 by Victorino Herrera, a local Andean farmer, after whom the animal is named. That skeleton was incomplete, but the discovery of a complete skull in 1988 by palaeontologist Paul Sereno provided enough information to make a complete reconstruction. Herrerasaurus is important because it shows palaeontologists what dinosaurs were like just after or at the time they first evolved. 

From The Expert

When Herrerasaurus lived, dinosaurs were actually quite rare. They had yet to become dominant creatures. Close relatives of Herrerasaurus lived in North America during the Late Triassic, but these primitive dinosaurs went extinct by the Jurassic.


Sizing it Up


Compare to:

1m / 3.28ft

Herrerasaurus was double the height of Velociraptor.

1 human
1 human
1 m / 3.28 ft


Number of people head-to-toe to reach the top of Herrerasaurus. (average human height 1.76 m / 5.7 ft)

Compare to:

4m / 13.12ft

Herrerasaurus was double the length of Velociraptor.

1 human
1 human
4 m / 13.12 ft


Number of people side by side touching finger tips to match this length (average arm span 1.7 m / 5.58 ft ).

Compare to:

210.01kg / 463.0lbs

Over ten times as heavy as Velociraptor.

herrerasaurus weight

Number of people weighing 70.31 kg / 155 lbs needed to match the weight of Herrerasaurus.


Dino On The Go!

Estimates of Herrerasaurus' speed suggest it might have been as fast as a Tyrannosaurus rex.

40kph / 24.85mph

  • Horse 52 kph / 32.3 mph
  • Herrerasaurus40 kph / 24.85 mph
  • Cheetah 120.7 kph / 75 mph

22.5kph / 14mph

The average human sprint speed.


Family Album

Family Album

Herrerasaurus' family tree is contentious. Some scientists say it is a member of the theropods - the group that contains all of the carnivorous dinosaurs like Tyrannosaurus. Others argue that it was an early saurischian, the group that encompasses the theropods and sauropods. Then there are those who say Herrerasaurus was so primitive that it evolved before the dinosaurs split into the major subgroups of theropod, sauropod and ornithischian. 



Herrerasaurus Vision

As a predator, Herrerasaurus would have had binocular vision so that it could judge distances and time to attack.

Herrerasaurus Vision.

Human Vision

The human field of view is roughly 180 degrees.

Human Field of View

The Skinny On Their Skin


There is a possibility that Herrerasaurus sported simple feathers, because so many other theropods did.


What's In The Nest?

Herrerasaurus Egg

We don't know much about Herrerasaurus' eggs.



herrerasaurus brain size

Herrerasaurus had a simple, tubular brain, which would have been at the other end of the spectrum from the enlarged and complex brain of the birds. Herrerasaurus was no bird brain: it was much dumber!



Quite The Bite

Herrerasaurus had a dual-hinged jaw so that it could hold prey more tightly. Once a victim had been caught, there would have been no escape.



Good Eatin'

Plant Icon

Herrerasaurus' forelimbs were equipped with three large, recurved claws for grasping and raking. It even had a semi-opposable thumb to help capture prey. It fed on small and medium-sized herbivores such as Pisanosaurus, rhyncosaurs and synapsids.


Parental Guidance

Herrerasaurus Parent and Child

We do not know if Herrerasaurus looked after its young. 


True Colours

Color Wheel

If Herrerasaurus had feathers, they might have been colourful for use in behavioural displays.