N.Vietnam, Ha Tinh Prov., Huong Son Distr., Son Hong Municipality, around point 18°34′06′'N, 105°11′40′'E. Primary broad-leaved evergreen riparian forest with Platanus kerrii and Duabanga grandiflora along rocky Song Con river valley composed with shale and gray sandstone at elevation 250-300 m a.s.l.
Creeping terrestrial herb. Flowers greenish. Leaves deep green above, very light green below. Very common. Co-dominant of herb forest stratum.