Taxonomic studies on the Chinese Costaceae I: a new name and two new combinations

Costus chinensis and C. oblongus (Costaceae) has been previously placed in synonymy under C. lacerus. Our critical examination of herbarium specimens including type material demonstrates that they are morphologically distinct from each other. Therefore, the independent specific status of C. chinensis and C. oblongus is reinstated. According to recent studies, Costus chinensis as well as other two Chinese species, C. oblongus and C. viridis, should be transferred to Hellenia. Thus, a new name for C. chinensis, and two new combinations are proposed. A detailed description of C. chinensis along with a distribution map of three allied species is also provided.