69. Begonia hongkongensis F. W. Xing, Ann. Bot. Fenn. 42: 151. 2005.
香港秋海棠 xiang gang qiu hai tang
Herbs. Rhizomes ca. 3 mm in diam. Stems 10.3-21 cm. Leaves basal and cauline; stipules lanceolate, 1-2 cm, membranous; petiole 5.2-9.4 cm, apex sparsely shortly hairy; blade oblong-ovate to rhombic-ovate, slightly asymmetric, 7-13.6 × 2.3-4.5 cm, abaxially sparsely shortly hairy, adaxially glabrous, venation palmate-pinnate, 5- or 6-veined, base slightly oblique, cuneate to broadly cuneate, margin irregularly and remotely serrate, very shallowly lobed, apex acuminate to caudate. Inflorescences glabrous; peduncle ca. 5 cm; bracts lanceolate, ca. 8.5 × 3 mm, membranous, glabrous, apex aristate. Staminate flowers: pedicel 7-14 cm; tepals 4, white, outer 2 broadly ovate or oblong, ca. 10 × 9 mm, glabrous, inner 2 ovate, ca. 8 × 4 mm; stamens numerous; filaments entirely fused, 1.1-1.4 mm; anthers oblong or obovoid, 1-1.3 mm. Pistillate flowers: pedicel pale pinkish, 2-2.5 cm; tepals 5, white, 0.7-1.2 × 0.6-1.2 cm, glabrous; ovary ovoid, glabrous, 2-loculed; placentae axile, bilamellate; styles 2, ca. 3 mm, free; stigmas spiraled. Capsule nodding, 1.8-2.9 cm, unequally 3-winged; abaxial wing ligulate, ca. 2.8 × 1.6 cm, apex obtuse; lateral wings smaller. Fl. Jul-Sep, fr. Oct-Dec.
● Evergreen secondary forests, on moist rocks by streams in ravines; 100-400 m. Hong Kong.
Begonia hongkongensis is similar to B. tsoongii, which is known only by the type gathering made in 1916 from S Guangxi. It differs from the latter by having cauline leaves, leaf blade margin very shallowly lobed, irregularly and remotely serrate, and apex acuminate to caudate.