N.Vietnam, Bac Kan Prov., Ba Be Distr., Nam Mau Municipality, Ba Be National Park around point 22o25′36′'N 105o37′50′'E.
Heavily logged primary evergreen dry broad-leaved forest on very steep slopes and cliffs composed with crystalline highly eroded marble-like limestone along Ba Be lake at elevation 200-250 m a.s.l.
Lithophyte on vertical shady cliffs. Occasional.
HLF 601a 22 Dec. 2002. Flowerd in Vinh garden under No P-10627 (photo).
Coll. Phan Ke Loc, L.Averyanov, Hoang Van Chat, Do Hoang Chung, Nguyen Manh Hung, Vu Hong Van, Nguyen Tien Vinh, Mai Van Xinh. Grant from Henry Luce Foundation.