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Herrerasaurus

'Herrera's lizard'

WWD

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

They call it home

Herrerasaurus fossils have been found in the Ischigualasto Formation of north-western 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. The Ischigualasto landscape was a floodplain dominated by rivers and studded with volcanic activity 230 million years ago. Today, it is an arid, barren landscape.

What big teeth you have

What big teeth you have

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

The most fantastic find

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.

Herrerasaurus features

Herrerasaurus features Height: 1m (3.28ft)
Length: 4m (13.12ft)
Weight: 210.01kg (463lbs)
Top speed: 40kph (24.85mph)
Vision: As a predator, Herrerasaurus would have had binocular vision so that it could judge distances and time to attack.
Skin: There is a possibility that Herrerasaurus sported simple feathers, because so many other theropods did.
Brain: 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!
Prey: 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.
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.

Herrerasaurus facts and theories

Herrerasaurus facts and theories

  1. Herrerasaurus' forelimbs were less than half the length of its hindlimbs but were much longer than those of T. rex.
  2. 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.
  3. The Valley of the Moon in Argentina, where Herrerasaurus was found, is one of the world's richest Triassic fossil sites.
  4. 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.