Notes on the Term “Tangut” in Botanical Names

Originally Tangut refers to a branch of the Qiang tribe in western China during the Sui and Tang Dynasties, ie. Dangxiang Qiang. Dangxiang Qiang gradually grew stronger in the Northern Song Dynasty, and established the Western Xia regime. They called themselves Daxia. We collected more than 40 botanical names that had the stem “Tangut” in the specific epithets. We analyzed their protologues, determined the collecting localities of their holotypes, lectotypes or syntypes in order to delimitate the geographical range of the Tangut region in floristics. Previous research results on the Tangut region were also considered. We suggested that the north boundary of Tangut region lied at the south slope of the Qilian Mountains (northernmost point at Jingtie Mountain), and then extended southwards through the Tao river reaches, ended at Burgan Buda Mountains and Amen Mountains, the west boundary started from the eastern margin of the Qaida Basin (Qaida Basin not included) and the east boundary extended from the Tao River reaches to northeastern Sichuan, roughly lied at the north of Song pan and Li Xian. We know that much more facts should be considered to deliminate the range of a flora region and it’s not enough to consider only the type localities of some taxa. However, considering the scope of this flora region is not large and we have analyzed more than 40 taxa, our analysis could be regarded as an exploratory attempt to delimitate the boundaries of a flora region from a historical viewpoint.