2025 Volume 51 Issue 2 Pages 67-75
The altitudinal and latitudinal distributions of Shortia rotundifolia sensu lato were compared between the Ryukyus of Japan and Taiwan. A significant difference in altitude values was found between the Ryukyus and Taiwan, and confirmed asymmetry of the distribution altitude of this species previously suggested. In addition, a negative correlation was found between altitude and latitude values in a region of the Ryukyus and Taiwan. Molecular phylogenetic analysis based on single-nucleotide polymorphism data revealed two major clades comprising plants from Amami and Okinawa Islands of the Ryukyus, and from Iriomote Island of the Ryukyus and Taiwan. The latter clade included two subclades—one consisting of plants from Iriomote Island and the northern part of Taiwan, and another consisting of plants from central and southern Taiwan. These results suggested that the high mountain range between the northern and central parts of Taiwan likely acts as a biological barrier for this species.
