Pontederiaceae Kunth Monochoria vaginalis (Burm.f.) Presl S. Vietnam, Prov. Kontum. Evergreen primary forest along stream (Dak Mek river system) at 850-900 m alt. on W slope of Ngoc Linh mountain system abowe Muong Hoong village. Floating herb in water. Flowers blue. Common weed in rice field. VH 1360 14.04.1995 International Botanical Expedition of the U.S.A. National Geographic Society (grant No 5094-93)
Participants: L. Averyanov, N.T. Ban, N. Q. Binh, A. Budantzev, L. Budantzev, N.T. Hiep, D.D. Huyen, P.K. Loc, N.X. Tam, G. Yakovlev