FLORA OF VIETNAM. Fam. Urticaceae. Elatostema sp. N. Vietnam, prov. Son La, distr. Moc Chau, municipality Chieng Hac,. vicinities of Co Liu village (N 20°51' E 104°38'). Primary evergreen. broadleaved wet forest on very steep slopes and bluffs of remnant. karst limestone ridge at 900-1000 m elev. Terrestrial and lithophyte. forb on shady steep slope. Common. No NTH 2937   29 May 1999. International Botanical Expedition of the U.S.A. National Geographic. Society (grant No 6300-98). . Collectors: N.T.Hiep, P.H.Hoang, Averyanov L.