Haiba dragon (scientific name: Thalassomedon) is a marine reptile of plesiosauridae, named by Welles in 1943, which means "ruler in the sea". The body length of this species can reach 12 meters. The neck consists of 65 vertebrae, with a length of about 6 meters, accounting for 50% of the whole body. The skull is 47cm long, the teeth are 5cm long, and the flippers are about 1.5-2 meters long. The sea basilon survived 95 million years ago in North America in the late Cretaceous Norman order, and its fossils have been found in different parts of North America. The genus is closely related to the lamosaurus, and there are 6 specimens of different preservation conditions.

It is a marine reptile that lived during the Late Cretaceous Senonian period approximately 95 million years ago. Belonging to the Stegosauridae family of the plesiosauriformes order, it is a long necked plesiosaur with a genus name in Greek meaning 'ruler of the ocean'. Fossils are mainly found in North America, especially in the Graneros shale layers of the Midwest United States. The body length can reach 12 meters, with a very long neck and 65 vertebrae, about 6 meters in length, accounting for half of the body length. The length of the skull is 47 centimeters, the length of the teeth can reach 5 centimeters, and the length of the fin like limbs is approximately between 1.5 and 2 meters.