Begonia hatacoa Buch.-Ham. ex D. Don

Herbs, 30-65 cm tall. Rhizome not seen. Stem branching twice or more. Leaves cauline; stipules lanceolate, 6-10 mm, membranous, apex acuminate; petiole 8-24 mm, densely brown hirsute; blade ovate-lanceolate to elliptic-lanceolate, asymmetric, 6-9.6 × 2.1-3.2 cm, abaxially brown pubescent, adaxially glabrous or subglabrous, venation palmate-pinnate, 5-7-veined, base slightly oblique, rounded or slightly cordate, margin remotely serrulate, apex long acuminate to caudate. Inflorescences glabrous; peduncle 2-3.1 cm; bracts narrowly elliptic to lanceolate, 5-8 × 1.5-3.5 mm, membranous, abaxially brown hirsute when young, apex acuminate. Staminate flowers: pedicel 5-10 mm; tepals 4, outer 2 triangular-ovate, ca. 5 × 3.5 mm, glabrous, inner 2 oblong, ca. 4 × 1.5 mm; stamens numerous; filaments free, ca. 1.5 mm; anthers reniform, ca. 0.8 mm. Pistillate flowers: tepals 5, unequal, largest broadly ovate, ca. 7 × 4 mm, glabrous, smallest oblong or lanceolate, 6-7 × 1.5-2 mm; ovary glabrous, 2-loculed; placentae axile, bilamellate; styles 2, fused at base; stigmas 2-cleft, spiraled. Capsule pendulous, oblong, ca. 14 × 8 mm, unequally 3-winged; abaxial wing broadly falcate, 1.5-2 cm × 6-9 mm, apex rounded; lateral wings smaller, ca. 4 mm. Fl. Oct-Nov, fr. Dec-Jan.

E. Himalaya (Nepal to Bhutan), Assam.

SE Xizang (Mêdog) [Bhutan, N India, Nepal].

1200-2000 m

Evergreen broad-leaved forests, on rocks in shaded moist environments on slopes or by streams; 1200-1500 m.