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.
Gongbusaurus
Gongbusaurus is a genus of ornithischian, perhaps ornithopod, dinosaur that lived between about 160 and 157 million years ago, in the Late Jurassic period. A small herbivore, it is very poorly known. Two species have been assigned to it, but as the original name is based on teeth, there is no concrete evidence to connect the two species. Its fossils have been found in China.