Houphan Prov., Viengxay Distr., Vieng Xai village, around point 20°23'41.3''N 104°13'44.5''E. Primary and secondary broad-leaved evergreen dry forest on very steep rocky slopes of highly eroded mountains composed by solid marble-like limestone at elev. 800-950 m a.s.l. Terrestrial and lithophytic stemless herb in limestone pockets on shady rocks. Leaves to 1 m long and 4 cm wide. Not rare.