Abstract:Trimeresurus sichuanensis was a newly described species from China in 2011, with only two known localities: Hejiang County, Sichuan Province, and Jiangkou County, Guizhou Province. During our field surveys in July 2020, one adult female Trimeresurus specimen was collected from Hunan Hupingshan National Nature Reserve (HHNNR), Hunan Province, China. After a detailed morphological examination, it exhibits the same characteristics as T. sichuanensis (Table 1), we believed this is a species which never been reported from Hunan Province. We then used four fragments of the mitochondrial genes Cyt b, ND4, 12S rRNA and 16S rRNA to reconstruct the phylogenetic tree of Trimeresurus to identify the position of the newly collected specimen from Hunan Hupingshan National Nature Reserve (Fig. 3). The result shows the HHNNR sample clustered together with the paratype specimen (YBU030116) of T. sichuanensis from Hejiang County, Sichuan Province, and there’s nearly no genetic distance between these two samples. Thus, we here report T. sichuanensis as a new record in Hunan Province, China. Our discovery indicates that a broader distribution range of T. sichuanensis in the Wuling Mountains and nearby areas. In order to provide useful data for the conservation of this endemic species, researches on its potential range and population status should be a focus.