FLORA OF VIETNAM Rubiaceae Leptomischus hiepii L. Wu, K.S. Nguyen & Aver. sp nov. Son La province, Muong La district, Muong La N.R., Ngoc Chien commune. Primary evergreen broad-leaved forest along streams at the base and slope of sandstone mountain, around point 21.61032° N 104.10576° E, at elevation of 1350 m a.s.l. Lithophytic perennial herbs around 30-45 cm tall, stem sub-erect, flower pure white, calyx and corolla glabrous adaxially, white pubescence abaxially, very common at waterfalls and humid places in a restricted area (around 2500 m2). March 2, 2019, Nguyen Sinh Khang, Nguyen Duc Thang et al., NSK 1153 (holotype CSFI; isotype CSFI, HN, LE 01058686, LE 01058688, LE 01073034 - photo), including living plants and DNA samples (HN)