Vientiane Prov., Kasi Distr., Tam Tai village, about 10 km to the NW of Kasi town (19°12′57”N 102°14′59”E).
Remnants of primary and secondary broad-leaved evergreen forest on very steep rocky slopes of remnant mountain composed with highly eroded solid crystalline limestone at elevation 500-650 m.
Woody vine to 10 m long on rather open rocky slope. Flowers purple-violet. Occasional.
LA-VN 751 24 March 2013 Coll.: L.Averyanov, N.S.Khang, S.Lorphengsy