N.Vietnam, Bac Kan Prov., Ba Be Distr., Nam Mau Municipality, Ba Be National Park around point 22o23′22′'N 105o37′09′'E.
Selectly logged primary evergreen closed broad-leaved forest on slopes composed with crystalline highly eroded marble-like limestone at elevation 300-400 m a.s.l.
Terrestrial herb in shady place. Flowers dirty green with brown marks. Occasional.
HLF 635 23 Dec. 2002.
Coll. J.Regalado, Nguyen Tien Hiep, L.Averyanov, Do Hoang Chung, To Van Thao, Vu Hong Van, Nguyen Tien Vinh, Mai Van Xinh. Grant from Henry Luce Foundation.