About 250 million years ago, reptiles called erythrosuchids - loosely translated as 'red crocodiles' - flourished. These reptiles had huge heads and powerful jaws, and included the largest land predators to have lived on Earth by that time.

One of these was an animal called Garjainia. About three metres long, the carnivores walked on four legs and looked like modern-day Komodo dragons. Their remains have been found in South Africa and Russia.

Not much is known about the Russian specimens, but scientists from the Museum and the University of Birmingham have collaborated with experts from Oxford, Moscow and Buenos Aires to study fossilised remains of skeletons from seven individuals, including a nearly complete skull.

It was thought that the skull fossils belonged to two distinct species of erythrosuchid called Garjainia prima and Vjushkovia triplicostata. On closer inspection, it was found the bones are all similar enough to be considered only a single species, Garjainia prima.

The team also confirmed that erythrosuchids like Garjainia had huge heads in comparison to their bodies.

The findings have been published in Royal Society Open Science.

Prof Richard Butler is a palaeontologist at the University of Birmingham and lead author of the study. He says, 'There are lots of animals from this period of time that were bizarre and interesting but we don’t know much about them at all.

'I am studying them because I want to know more about the evolutionary origins of a group of animals called archosaurs. That includes the dinosaurs, as well as birds and crocodiles.'

Although they never lived alongside the dinosaurs, erythrosuchids are distantly related to them. They would have dominated the ecosystem just like their dinosaur relatives.