Cao Bang Prov., Bao Lac Distr., Hong An municipality, Mi Lung village.
Primary broad-leaved and mixed humid evergreen forest (with Podocarpus, Pinus, Fokienia and Tsuga) on very steep slopes and along rocky ridge composed with solid crystalline highly eroded limestone at elevation about 1500-1550 m a.s.l. around point 22°49′15.4″N 105°49′53″E.
Large humus epiphyte on old tree in shady humid karst funnel on rocky mossy mountain slope. Flowers dull yellow to almost white, perianth segments dirty purple-brown, anthers and stigma dull yellowish. Very rare.