FLORA OF VIETNAM Hydracharitaceae Vallisneria spiralis
N. Vietnam, prov. Cao Bang, distr. Ha Lang, municipality An Lac, vicinities of Phia Deng village (N 22°43′ E 106°36′), about 36 km to E from Cao Bang town. Aquatic plant in shallow slow-water place of stream on alluvial valley between limestone ridges at 500 m alt. Abundant.
CBL 788 29 Nov. 1998 International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)