S. Vietnam, Prov. Lam Dong, distr. Lac Duong, municipalite Da Chay, vicinities Klong Lanh village, 32 km to NNE from Dalat city (N 12° 08′, E 108° 39′). Open spring grassy-sedges swamp on high terrace of river valley at the base of hills with old open Pinus kesiya forest at 1450 m alt. in 6-7 km from Bi Dup main peak to the W. Small aquatic plant with erect inflorescence up to 10 cm lg in small swamp puddles. Flowers blue-violet. Rare. VH 3965 14.04.1997 International Botanical Expedition of the U.S.A. National Geographic Society (grant No 5803-96)