원산지 : 중국(Yixian, Liaoning, China)

Hyphalosaurus is an extinct reptile in the Choristodera order, among the most interesting fossil animals found in the Early Cretaceous Yixian Formation in Liaoning Province, China, formed around 130-120 million years ago.

Somehow, the slab and counterslab of the holotype were given to different groups of researchers. Each described the taxon and published their results independently, giving the animal two different names. It was quickly recognized that Sinohydrosaurus and Hyphalosaurus were mirror images of one another and in fact represented the same specimen. Sinohydrosaurus is considered a junior synonym of Hyphalosaurus, because the latter name appeared in publication before the former.

Hyphalosaurus fossils are relatively widespread in the Yixian beds. Entire growth series are known, from embryos in eggs to fully-grown adults. This animal achieved an adult body size of about 0.8 meters