The dimetron, was not a dinosaur but looked very similar. In fact it is closer to the first mammals to reptiles.
This ancestor of mammals was the dominant predator of its time, during the Permian period of the Paleozoic era, made between 280 and 260 million years.
Could reach 3 meters long and had a long tail. A short legs and an elongated body provided them with a motion similar to those of the current monitors.
Another feature is its teeth Dimetrón two different types of teeth: a Shredder and a very sharp cuspids heartbreaking.
But the most distinctive feature is the spectacular dimetrodonte sail on its back. The candle used it, probably, to regulate body temperature because their large surface area allowed to warm up or cool efficiently. The flap was supported by the neural spines, each one sprang from an individual vertebra. You may also wear the dorsal fin in the courtship of mating or to ward off other predators.
The Dimetrón was a fierce predator that used two pairs of sharp pointed canines for tearing the skin of their victims. With the jaws closed, the Dimetrodon appeared to be smiling, but when he opened and showed his wide mouth, his appearance was not friendly at all. His jaws were so large that probably could devour animals of the same size.
Nothosaurus is an extinct genus of sauropsids (reptiles) Triassic marine, was among the first plesiosaurus (like the famous Elasmosaurus). Its name means "fake lizard" and who were not lizards like today's or even a dinosaur.
His teeth, very sharp as daggers, which also fit together those in both jaws, was a perfect trap for fish. Nothosaurus could close the mouth with great force but the muscles that allowed him to reopen it were very weak. Some of the best preserved fossils preserve the skin and drawing show that Nothosaurus had webbed feet, suitable for both the aquatic environment and to the land.
They could spend part of their life on land, on the sand and rocks. The tips allowed them to walk and move awkwardly arched his back, like lions today. You probably arrived on shore to stretch out, relax and warm in the sun, capturing prey on the pools of the shore and to reproduce by laying eggs. Breathed air, as shown by the two nostrils at the top of his nose, and although it was undoubtedly a stylish swimmer, was not so well adapted to an aquatic lifestyle as full-time as Opthalmosaurus ichthyosaurs.