FLORA OF VIETNAM
Rubiaceae
Ophiorrhiza amplifolia Drake

Ha Giang Prov., Quan Ba Distr., Can Ty Commune, Sin Suoi Ho Village, around point 23.09566°N 105.02142°E. Very steep mountain slopes composed of solid highly eroded karstic limestone at elevation 800–1000 m a.s.l. Remnants of primary evergreen broad-leaved and coniferous (with Calocedrus rupestris and Xanthocyparis vietnamensis) humid forest. Terrestrial herb to 1.5 m tall on shady very steep rocky slope. Flowers white with greenish apex. Very common. 11 October 2019, L. Averyanov, Nguyen Sinh Khang, T. Maisak, VR 1590 (HN, LE01067075, LE01070186).