Phu Tho Prov., Tan Son Distr., Xuan Son Municipality, Du village, around point 21°06’57”N 104°57’17”E (Xuan Son national park). Primary broad-leaved closed wet forest on very steep rocky slopes and cliffs of low remnant mountains composed with highly eroded solid marble-like limestone at elevation 400-500 m a.s.l. Lithophytic and terrestrial tuberiferous herb on very steep rocky slope and on cliffs. Occasional.
Coll.: L.Averyanov, P.K.Loc, N.T.Vinh, L.T.Son HAL 12681a 16 February 2009 (holotype)
Flowered under cultivation in June-July 2010.
d-EXSICCATES OF VIETNAMESE FLORA 0167/HAL 12681aa (LE)