Elatostema recurviramum (Urticaceae), a New Cave-dwelling Species from Guangxi, China

A new species, Elatostema recurviramum W. T. Wang & Y. G. Wei (Urticaceae), from Guangxi, China, is described and illustrated, and its affinities are discussed. It most closely resembles E. cyrtandrifolium (Zoll. & Moritzi) Miq., from which it differs in the recurved stems and branches, the denticulate margin of the leaf apex, the larger, ovate stipules, the presence of densely distributed cystoliths on the blade midrib, and the glabrous, lineolate achenes. The new taxon was collected from a limestone cave and is considered to be Critically Endangered (CR) according to IUCN Red List criteria.