N. Vietnam, Tuyen Quang prov., Na Hang distr., Thanh Tuong municipality, near Ban Bung village (22°16′26′'N, 105°25′58′'E). Primary broad-leaved evergreen wet forest on very steep limestone slopes of highly eroded remnant limestone ridge at elev. 700-750 m a.s.l. Lithophyte herb on mossy wet rocks. Spathe light green, apex of inflorescence yellow. Inflorescence stalk and petiole green with brownish irregular spots. Not common. HAL 133 20 March 2001