N.Vietnam, Bac Kan Prov., Ba Be Distr., Nam Mau Municipality Nam Dai village, Ba Be National Park around point 22025′ 651′'N 1050 35′ 613′'E. Primary closed evergreen broad-leaved forest on top of remnant mountains composed with crystalline highly eroded marble-like limestone at elevation 704 m a.s.l with dominant of Nghien (Burretiodendron). Herb on rock. Leave violet beneath, Flowers with tepals white. In open place, common HLF 566. 21 Dec. 2002.
Coll. Nguyen Tien Hiep, Jacinto Regalado, Duong Van Xy, Bang Tien Sy Grant from Henry Luce Foundation.