97. Begonia masoniana Irmscher ex Ziesenhenne, Begonian. 38: 52. 1971.
铁甲秋海棠 tie jia qiu hai tang
Herbs, rhizomatous. Rhizomes creeping, 1.5-2.3 cm in diam. Leaves all basal; stipules triangular, manifestly keeled; petiole 10-30 cm, hirsute-villous; blade abaxially pale green, adaxially with broad blackish brown (red abaxially) bands along main veins, obliquely broadly ovate to suborbicular, 10-25 × 9-20 cm, abaxially sparsely villous or hispid on veins, adaxially with many hairy tipped pustules, sparsely long setose or hirsute, basally 5-7-veined, base deeply cordate, margin densely denticulate, apex acuminate or shortly caudate. Inflorescences axillary; peduncle 10-54 cm, sparsely glandular pilose; pedicel 5-14 mm; bracts and bracteoles ovate or oblong to lanceolate, 3-5 × 2-3 mm, membranous, margin glandular ciliate, apex acute, caducous; flowers 20-100 in a dichasial cyme. Staminate flower: tepals 4, outer 2 broadly ovate or suborbicular, 5-11 × 6-12 mm, inner 2 oblong, 5-8 × 2-4.5 mm, apex obtuse; androecium actinomorphic; stamens 40-55; anthers obovoid, apex truncate or subemarginate. Pistillate flower: tepals 3, outer 2 broadly ovate, oblong-obovate or suborbicular, (6-)8-12 × (4-)7-13 mm, abaxially glandular hispid, apex rounded, inner 1 oblong or obovate, 5-7.5 × 2-4.5 mm, apex obtuse; ovary oblong, red glandular hispid, placentae parietal; styles 3. Capsule nodding, oblong to ellipsoid, 9-13 × 5-6 mm, reddish, glandular hispid, unequally 3-winged, largest wing obliquely lunate or ligulate, 4-9 mm. Fl. Mar-Sep, fr. Jun-Sep.
Rocky limestone slopes, in caves under dense forests or shrubberies; 100-300 m. Guangxi (Daxin, Pingxiang) [Vietnam].
Begonia masoniana var. maculata S. K. Chen et al. (Acta Bot. Yunnan. 8: 222. 1986) was described from a cultivated plant in Kunming, Yunnan. However, it is from Vietnam and does not occur wild in China. It has subsequently been raised to species rank under the name B. variegata Y. M. Shui & W. H. Chen (Acta Bot. Yunnan. 27: 372. 2005), based on the same type.