Anshunsaurus is a genus of within the family Askeptosauridae. Fossils have been found from Middle Triassic deposits in Guizhou, China. Three species are known: the type species A. huangguoshuensis (named in 1999), the slightly older species A. wushaensis (named in 2006), and the species A. huangnihensis (named in 2007).
The type species of Anshunsaurus, A. huangguoshuensis, was named in 1999 from the Ladinian or Carnian age Falang Formation in Guanling County. Although several complete skeletons are known, most specimens are crushed in either dorsal (top) or ventral (bottom) view. The holotype of A. huangguoshuensis, IVPP V11835, is preserved in dorsal view while a second specimen, IVPP V11834, is preserved in ventral view. Based on these specimens, A. huangguoshuensis grew to about in length. Although the tip is not preserved in any specimen, the tail made up at least half of the animal's length. A juvenile specimen of A. huangguoshuensis was described in 2015.
A second species, A. wushaensis, was named in 2006 from Xingyi. A. wushaensis is slightly smaller than A. huangguoshuensis and has a smaller head relative to its body length. It also has shorter with ridges on their upper surface, a shorter fourth digit on the hand, a well-developed entepicondyle on the humerus, and a shorter jugal bone. A juvenile specimen of A. wushaensis was described in 2007, making Anshunsaurus the only thalattosaur with a known ontogeny other than Xinpusaurus. The pectoral girdle and are asymmetrical in this specimen, suggesting that the bones on the left and right sides of the animal did not ossify at the same rate while it was growing.
In 2007 a third species of Anshunsaurus, A. huangnihensis, was described from Xingyi. It is distinguished from the other two species on the basis of the shape of its coracoid, a bone of the pectoral girdle.
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