They are the first ever, true, vertebrate land-lubbers; the very first reptile...Petrolacosaurus.
— Allen, describing Petrolacosaurus

Petrolacosaurus (name meaning "Rock Lake lizard") is a genus of primitive diapsid lizard reptile that originated during the Carboniferous. It was also the very first and earliest reptile ever to evolve.


Era & DiscoveryEdit

Petrolacosaurus lived during the Carboniferous period, 350-280 million years ago. It shared its environment with the giant insects and amphibians is lived alongside with. Petrolacosaurus was among the very first reptile that ever lived on Earth.

Physical AttributesEdit

Petrolacosaurus was small, about 40 centimeters long, and it had the body shape similar to a modern-day lizard, like the slender body and splayed out limbs. It also had a row of bumps and knobs running down its back. It was green with white patterns and had a shade of red around its eyes.

Although it was very small, Petrolacosaurus often hunted smaller insects on the forest floors of the Carboniferous. However, the creature itself was fairly low on the food chain.

Unlike amphibians, Petrolacosaurus, like all reptiles, had tough, scaly skin which trapped moisture inside their bodies, vital for all land dwellers. Because they didn't dry out in the sun, they could venture away from water. They also had evolved a complex heart, which was much more efficient than their enemies. In fact, their hearts were the templates for our own. In the case of Petrolacosaurus, it was a powerful pump that pushed blood and oxygen around their bodies to their muscles so they could run at high speeds without stopping for a rest.

Behavior & TraitsEdit

Petrolacosaurus may have often spent time in wholes, but they had stamina and speed on their side, and therefore didn't need burrows or holes to avoid danger. This reptile was a carnivore which mainly fed on small insects, arthropods and maybe even the corpses of large animals like Mesothelae spiders.

Once hatched from eggs, baby Petrolacosaurus would be completely independent. Living on their own, they were vulnerable to attack from the supersized arthropods around during the Carboniferous. However, it was a relatively fast animal, therefore it could outrun its pursuers.

But in the next episode, Allen gets the group of Petrolacosaurus into the Aviary with frogs and lizards.


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