Mosasaur
Mosasaurs (from Latin "Mosa" meaning the 'Meuse river', and Greek σαύρος "sauros" meaning 'lizard') are an extinct group of large marine reptiles containing 38 genera in total. Their first fossil remains were discovered in a limestone quarry at Maastricht on the Meuse in 1764. Mosasaurs probably evolved from an extinct group of aquatic lizards known as aigialosaurs in the Early Cretaceous. During the last 20 million years of the Cretaceous period (Turonian-Maastrichtian ages), with the extinction of the ichthyosaurs and pliosaurs, mosasaurs became the dominant marine predators. They became extinct as a result of the K-Pg event at the end of the Cretaceous period, about 66 million years ago.
Saltoposuchus
Fossils found in Germany indicate that "Saltoposuchus" existed in Europe, or more appropriately, Laurasia. The Mesozoic Era has been regarded as "The Age of Reptiles" so "Saltoposuchus" lived among many different species including the earliest species of pterosaurs and other bipedal reptilians. Archosaurs, the ancestor to Crocodylomorpha, made its first appearance in the middle of the Triassic era. This is also the period in which the earliest mammals started appearing. Therapsids dominated the Early - Middle Triassic Period, but as time went on, therapsids started becoming extinct and archosaurs became the dominant group of reptiles. After the Permian–Triassic extinction event wiped out 90% of species in the world, conifer forests started to recover, species started occupying and thriving in newly found ecological niches, Pangaea started splitting into Laurasia and Gondwana, and the air was very arid with hot summers and cold winters. After marine life had been wiped out by the mass extinction event, the Triassic waters were populated with very few families of fish. The Triassic Period showed the first development of modern stony corals and a time of modest reef building activity in the shallower waters of the Tethys near the coasts of Pangaea. During the Mesozoic Era, early mammals, reptilian species, and other insects populated the land. Insects that had survived the mass extinction and were existing during this time include spiders, scorpions, millipedes, centipedes, and a newer group of beetles.