Anshunsaurus huangnihensis sp.nov.,described in this article,was erected from the early Late Triassic limestone in Xingyi County,Guizhou Province.It is very similar to Anshunsaurus huangguoshuensis and A.wushaensis in such features as tri-radiate jugal,about 38 presacral vertebrae and 17cervical vertebrae,the formula of phalange being 2-3-4-5-4.However,the distinct differences among them are that the anterior margin of coracoid of the new species is slightly shorter,and the posterior margin extends longer postoventrally.The characters are very similar to those of Askeptosaurus italicus from Grenzbitumenzone(Anisian/Ladinian)and Endennasaurus acutirostris from Norian in Europe.All these features suggest that the new species belongs to transitional species between A.italicus and A.huangguoshuensis and provides important evidences for the evolution of the long-necked thalattosaur phylogenetics and paleobiography.