Begonia lanternaria Irmsch.

Herbs. Rhizomes elongate. Leaves basal; stipules caducous, oblong-ovate, 9-10 × 4-5 mm, membranous; petiole 8-23 cm, sparsely villous; blade abaxially pale brown-green, adaxially deep brown-green, ovate to broadly ovate, asymmetric, 11-13 × 12-14 cm, glabrous, venation palmate, 5-veined, base strongly oblique, deeply cordate, margin densely minutely serrulate, apex shortly caudate. Inflorescences 18-25 cm tall, glabrous; bracts broadly elliptic to broadly ovate, 5-9 × ca. 5 mm, margin glandular ciliate. Staminate flowers: pedicel 9-10 mm; tepals 4, pinkish, outer 2 broadly ovate, 7-9 × 6-7 mm, abaxially subglabrous, inner 1 oblong, ca. 6 × 2 mm; stamens numerous; filaments ca. 1.8 mm; anthers cuneate-obovoid, ca. 1 mm, apex emarginate. Pistillate flowers: pedicel ca. 2 cm; tepals 3, pinkish, outer 2 broadly ovate, inner 1 smaller; ovary glabrous, 1-loculed; placentae parietal, bilamellate; styles 3. Capsule nodding, oblong-ovoid, ca. 1.2 cm, unequally 3-winged; abaxial wing subtriangular; lateral wings smaller. Fl. Aug, fr. Sep.

On limestone rocks at forest margins. Guangxi (Longzhou) [N Vietnam].