Unlike their crocodile relatives, these triassic monsters were warm-blooded and hunted on land. They were common throughout the Triassic and lived in all the warm regions of Pangaea. All of them had large heads, slicing teeth, thick necks, straight tails, and four legs which were positioned under the body. Rauisuchus itself was a fairly average member of the group which lived in the arid regions of Western Pangaea (now the Americas), as was Vivaron. Vivaron's close relative Teratosaurus was significantly larger, as were Postosuchus and Polonosuchus, all of them inhabiting the wetter regions in North-Western Pangaea (North America and Europe). Scolotosuchus, on the other hand, was smaller and more agile, and lived in the coastal plains of Northern Pangaea (Russia).
Rauisuchids in GURPS
Phytosaurs in GURPS
Although only distantly related to crocodilians, phytosaurs looked almost exactly like them. The most noticeable differences were that the ends of their snouts curved down and their nostrils were positioned near their eyes. All known genera are from the late Triassic, although they are believed to have evolved near the beginning of the period. They lived in the tropical regions of Pangaea.
Angistorhinus
A large phytosaur with narrow jaws and slender teeth, ideal for catching fish. Rutiodon was similar in both size and diet, while Machaeroprosopus was a smaller fish-eater.
Angistorhinus
Mystriosuchus
A sea-dwelling animal, Mystriosuchus had limbs which were more flippers than legs. It mostly ate soft-bodied invertebrates.
Mystriosuchus
Nicrosaurus
Nicrosaurus took the opposite evolutionary path to Mystriosuchus, adapting to the land. Although not especially large by phytosaur standards, its teeth were well suited to big game.
Nicrosaurus
Paleorhynus
A small generalist, which would eat fish, carrion, or smaller land animals as the opportunity arose.
Paleorhynus
Smilosuchus
The largest known phytosaur had long fangs at the tip of its jaw for grabbing large animals. It was likely an ambush predator, like modern crocodiles. Brachisuchus was another big ambush predator.
Smilosuchus
Ornithosuchus in GURPS
A distant relative of crocodilians, the 'bird crocodile' was a long-legged reptilian predator which lived in North-Western Laurasia (the continent which would later split to form North America and part of Europe) during the late Triassic. It was fully terrestrial and warm-blooded, typically walking on all fours but lifting its fore-legs off the ground to sprint. Its triangular head tapered to a narrow snout, bristling with teeth, some of them long enough that the opposite jaw was shaped to allow them space to stick out.