Quang Tri Prov., Huong Hoa Distr., Huong Lap municipality, Cup village, around point 16°55’11”N 106°34’36”E. Poor remnants of primary broadleaved evergreen forest on very steep slopes of river valley composed with stratified shale at elev. about 350 m a.s.l. Creeping terrestrial herb on steep shady river slope. Common.