澜沧秋海棠 lan cang qiu hai tang

Herbs, dioecious. Rhizomes short, stout. Stems erect, 80-120 cm tall, 1.2-2.6 cm in diam., puberulous. Leaves cauline; stipules brown, ovate-triangular, 1.2-3.1 × 0.8-1.4 cm, glabrous, apex acuminate; petiole 15-40 cm; blade ovate or ovate-oblong, asymmetric, 10-35 × 7-20 cm, abaxially puberulous on veins, adaxially glabrous, venation palmate, 6- or 7-veined, base oblique, cordate, margin irregularly serrulate, apex acuminate. Inflorescences strongly reduced; bracts ovate, 0.7-1.4 cm, glabrous, apex acute and shortly cuspidate. Flowers fragrant. Staminate flowers: pedicel 1-2 cm; tepals 4, outer 2 greenish at base or white, abaxially puberulous, ca. 2.6 × 3.1 cm, inner 2 white, ca. 2.3 × 1.8 cm; stamens ca. 70; filaments 2-2.5 mm; anthers 4.3-4.8 mm. Pistillate flowers: pedicel 2.5-4 cm; tepals 4, white, outer 2 broadly ovate, 2.5-3.2 × 1.8-2 cm, inner 2 obovate or oblong, 1.8-2 × 0.7-1 cm; ovary obovoid, ca. 1 cm, subglabrous, 4-loculed; placentae axile, bilamellate; styles 4, stigmas 2-cleft, spiraled. Fruit berrylike, 4-horned. Fl. Feb-Mar, fr. Apr-Jul.

● Evergreen broad-leaved forests; ca. 1600 m. Yunnan (Lancang).

This species resembles Begonia roxburghii A. Candolle of the Himalayas but differs by its puberulous habit and the stem without red, linear dots.