Two new species of Sedum (Crassulaceae) from Taiwan

Based on our morphological observation, we proposed two new Sedum species in Taiwan. Sedum kwanwuense sp. nov. resembles S. morrisonense. However, it differs from the latter in having flatter and longer leaves, and occurring in different habitat, the former growing on humid, rocky slopes under the forest and the latter living on dry rocky slopes beyond the forest. Sedum taiwanalpinum sp. nov. is similar to S. brachyrinchum, but it can be distinguished from the latter by sepal and leaf morphologies (leaf linear-oblong to linear vs. spathulate to linear-oblong, and sepal unequal to subequal, spreading when blossom vs. unequal in length, erect to oblique when blossom). Our observations were supported by a former phylogenetic study. In this paper, besides providing taxonomic descriptions and line drawings of the two new taxa, we also organize an update key to native and naturalized species in Sedum in Taiwan for aiding the identification.