BEGONIACEAE 1. BEGONIA Linnaeus, Sp. Pl. 2: 1056. 1753.

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BEGONIACEAE
168. Begonia xanthina J. D. Hooker, Bot. Mag. 78: t. 4683.
1852.
黄 瓣 秋 海 棠 huang ban qiu hai tang
Herbs, to 40 cm tall. Rhizomes elongate. Leaves basal; stipules
caducous, ovate to narrowly triangular, margin entire, apex
acuminate to cuspidate; petiole 15–23 cm, subglabrous to sparsely
pilose; blade broadly ovate, asymmetric, 17–26 × 15–22 cm,
abaxially subglabrous or remotely pilose, adaxially glabrous,
venation palmate, base oblique, cordate, margin remotely and
finely serrulate, apex acute. Inflorescences glabrous; bracts
ovate, to 2.3 × 1.8 cm, glabrous, margin entire, apex acute.
Staminate flowers: pedicel 1.5–2 cm; tepals 4, yellow, glabrous,
outer 2 elliptic, 2.1–2.2 × 1.2–1.3 cm, inner 2 narrowly obovate,
ca. 2 × 0.9–1 cm; stamens numerous; filaments fused to halfway;
anthers oblong, apex acute. Pistillate flowers: tepals 5,
yellow, glabrous, unequal, obovate to oblong, largest 1.5–2.2 ×
1.4–1.6 cm, smallest 1.2–1.6 × 0.8–1.3 cm; ovary glabrous, 2-
loculed; placentae axile, bilamellate; styles 2; stigmas 2-cleft,
spiraled. Capsule nodding, unequally 3-winged; abaxial wing
falcate, ca. 1.7 cm; lateral wings smaller. Fl. Sep–Oct, fr. Nov.
Forests, rocky hills by streams; ca. 800 m. SW Yunnan [NE
India].
Begonia xanthina is a new distributional record reported for China
by Peng et al. (Bot. Stud. 47: 92. 2006). It resembles B. rex but differs
by the yellow tepals and the leaves, which lack long, setose hairs and
the horseshoe-shaped spot.
169. Begonia xingyiensis T. C. Ku, Acta Phytotax. Sin. 33: 263.
1995, not B. xinyiensis T. C. Ku (loc. cit.).
兴 义 秋 海 棠 xing yi qiu hai tang
Herbs, deciduous. Tubers globose, 6–10 mm in diam.
Leaves basal; stipules caducous, membranous; petiole 4–4.5
cm, villous; blade broadly ovate or orbicular, asymmetric, 4.5–6
cm, papery, sparsely villous, venation palmate, 7- or 8-veined,
base oblique, slightly cordate, margin irregularly serrate or biserrate,
apex obtuse. Inflorescences 4–8 cm tall, pilose; bracts
caducous, lanceolate, 2–3 mm, membranous. Staminate flowers:
pedicel 8–10 mm; tepals (3 or)4, purplish white, outer 2
broadly ovate to obovate, 8–9 × ca. 5 mm, inner 2 obovate-oblong,
ca. 7 × 4 mm; stamens numerous; filaments ca. 0.8 mm,
fused at base; anthers oblong, ca. 0.5 mm. Pistillate flowers: tepals
2, suborbicular, ca. 5 × 7 mm; styles 3, entirely fused. Fl.
Aug.
● On rocks in valleys; ca. 1100 m. Guizhou (Xingyi).
This species is similar to Begonia labordei but differs by its 2-
tepaled pistillate flowers.
170. Begonia xishuiensis T. C. Ku, Acta Phytotax. Sin. 33: 264.
1995.
习 水 秋 海 棠 xi shui qiu hai tang
Herbs, deciduous. Tubers globose, ca. 1.5 cm in diam.
Leaves 1 or 2 basal, with 1 or 2 smaller leaves on inflorescence;
stipules caducous, 3.6–6.7 × 5.7–8.9 mm, margin denticulate,
apex acute; petiole 9–14 cm, glabrous; blade purple abaxially,
broadly ovate, slightly asymmetric, 11–16 × 8–10 cm; glabrous,
venation palmate, 7-veined, base slightly oblique, shallowly
cordate, margin very shallowly denticulate, shallowly lobed on
upper half, divided to 1/3 of leaf length; lobes 3 or 4, apex
acuminate or acute. Inflorescences terminal, 6–32 cm tall, glabrous;
bracts caducous, lanceolate or ovate-lanceolate, 2–4 × 1–
2 mm, membranous. Staminate flowers: pedicel ca. 0.5 mm; tepals
2, broadly ovate, 6–11 × 6–12 mm; stamens 11–16; filaments
fused at base, 1.3–2.5 mm; anthers obovoid or subglobose,
0.8–1.1 mm, apex emarginate. Pistillate flowers: pedicel
1.5–3.1 cm; tepals 2, suborbicular, 7–10 × 6–12 mm; ovary glabrous,
3-loculed; placentae axile, bilamellate; styles 3, ca. 3.1
mm, fused at base; stigmas U-shaped. Capsule pendulous, unequally
3-winged; abaxial wing triangular, ca. 8 × 16 mm; lateral
wings smaller, ca. 5 mm. Fl. May.
● Forests, on shaded moist rocky slopes; 700–800 m. Guizhou
(Xishui).
This species is similar to Begonia summoglabra but differs by its
herbaceous, shallowly lobed leaves.
171. Begonia yingjiangensis S. H. Huang, Acta Bot. Yunnan.
21: 18. 1999.
盈 江 秋 海 棠 ying jiang qiu hai tang
Herbs. Rhizomes elongate. Stems very short. Leaves mostly
basal; petiole 10.5–15 cm, densely brown pubescent; blade
lanceolate, symmetric, 22–29.5 × 5–7.5 cm, abaxially densely
brown pubescent, adaxially glabrous, base cuneate, margin subentire
or slightly repand, apex acuminate or slightly caudate.
Inflorescences 17–20 cm tall, brown pubescent; peduncle 3–9
cm. Staminate flowers: pedicel ca. 1 cm; tepals 4, pink, outer 2
broadly elliptic, ca. 10 × 6 mm; stamens numerous; filaments
free, 1–2 mm; anthers oblong, ca. 1.5 mm. Pistillate flowers not
seen. Capsule nodding, ellipsoid, ca. 8 × 6 mm, brown pubescent,
2-loculed; placentae axile, bilamellate, unequally 3-
winged; abaxial wing ligulate, ca. 5 mm; lateral wings triangular,
ca. 3 mm. Fl. Aug.
● About 1100 m. Yunnan (Yingjiang).
This species is known only by the type gathering made in 1980.
172. Begonia yui Irmscher, Notes Roy. Bot. Gard. Edinburgh
21: 36. 1951.
宿 苞 秋 海 棠 su bao qiu hai tang
Herbs, deciduous. Tubers globose, 1.5–1.8 cm in diam.
Leaves 1(or 2), basal or sometimes 1 cauline; stipules caducous,
ovate, membranous, margin ciliate; petiole 4–12 cm, pilose or
subglabrous; blade ovate or broadly ovate, slightly asymmetric,
6–11(–14) × 5–7.5 cm, abaxially pilose, adaxially densely villous,
venation palmate, 5- or 6-veined, base slightly oblique,
shallowly cordate, margin minutely serrulate, apex shortly caudate.
Inflorescences terminal, racemose at base, 13–20 cm tall,
subglabrous; bracts ovate or oblong, 4–7 × 2–3.5 mm, membranous,
glabrous, margin finely glandular serrate near apex, apex
obtuse or rounded. Staminate flowers: pedicel ca. 1 cm; tepals
4, pink, outer 2 broadly ovate, ca. 8 × 6.5 mm, abaxially villous,
inner 2 elliptic, ca. 5.5 × 3 mm; stamens numerous; filaments