Hoa Binh Prov., Lac Son Distr., Tu Do Municipality, Mon village, around point 20°25′29”N 105°19′36”E. Primary broadleaved forest on steep rocky slopes of remnant mountain composed with solid crystalline highly eroded limestone at elevation about 500-700 m a.s.l. Terrestrial herb in shady place. Not rare. CPC 1566d (“small leaf, small flower”) 25 March 2011. Coll.: L.Averyanov, T.Maisak, L.Osinovetz et al. Fl. under cultivation at November 2015. Photos.