越南石梓 yue nan shi zi

Trees ca. 15 m tall. Branchlets 4-angled and densely yellow pubescent when young, becoming terete and glabrous, sparsely lenticellate. Petiole terete, 6-7 cm, channeled, yellow puberulent; leaf blade ovate-elliptic to ovate, 9-20 X 6-12 cm, abaxially bluish green, yellowish brown puberulent, and gray glandular, adaxially subglabrous except pubescent along veins, base broadly cuneate to subrounded, margin entire, apex acuminate to acute; veins 3 or 4 pairs, abaxially very prominent, reticulate, adaxially pitted. Inflorescences terminal cymose panicles, cymes narrowly divergent, proximal cymes as long as panicle; bracts deciduous, linear to linear-lanceolate, 5-7 mm, densely puberulent, black disc-shaped glandular. Calyx cup-shaped, almost rotate in fruit, 5-8 mm. Corolla yellow, ca. 3 cm; lobes 5, equal, rounded. Stamens slightly exserted. Ovary ovoid, pubescent. Style sparsely glandular. Fruit obovoid, 2.5-4 cm, fleshy. Fl. Jun-Jul, fr. Jul-Sep.

Open forests; 200-1000 m. Yunnan (Hekou Xian and Pingbian Xian) [Laos, Vietnam].