Abstract

The genus Elatostema (Urticaceae) in Taiwan is taxonomically revised based on morphological characters, molecular phylogeny and geographic distribution. Elatostema acuteserratum is not only found in Lanyu, but also in southern and eastern of Taiwan. Elatostema herbaceifolium is treated as a synonym of E. cyrtandrifolium and we also confirm the existence of its male inflorescence in Taiwan. Elatostema yonakuniense in Japan is treated as a synonym of E. microcephalanthum that is not an endemic species in Taiwan and Japan. Elatostema multicanaliculatum is treated as a synonym of E. oblongifolium and E. platyphylloides as a synonym of E. platyphyllum and these two taxa are no longer endemic species in Taiwan. In summary, there are a total of sixteen species in Taiwan, including one hybrid species.

Keyword: Elatostema, endemic species, Taiwan, taxonomic revision.