FLORA OF VIETNAM
Convallariaceae
Tupistra nganii K.S. Nguyen, Aver. & N. Tanaka, sp. nov.

Ha Giang prov., Quan Ba distr., Tung Vai commune, Thang village, around point 23°03ʹ00.4ʺN 104°52ʹ02.2ʺE, steep rocky slopes of river valley composed with eroded limestone at elevation 1000–1060 m a.s.l. Remnants of primary evergreen broad-leaved very humid forest. Lithophytic herb with leaves to 2 m long in shady wet rocks. Flowers pale yellow. Not rare. 19 October 2018, L. Averyanov, Nguyen Sinh Khang, T. Maisak, Truong Quang Ngan, VR 1015 (holotype – HN, isotypes HN, LE01042176, LE01042177, LE01042186). New species may be close to T. gracilis Aver. & N. Tanaka, but clearly differs in robust habit, leaves 1.4–2 m long (vs. leaves 0.6–1.6 m long), scape 12–18 cm long (vs. 4.5–18 cm long), bright yellow flowers and stamens as long or longer as as a pistil (vs. flowers light yellowish with almost sessile stamens much shrter than pistil).