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

162
BEGONIACEAE
Begonia calophylla Irmscher, Mitt. Inst. Allg. Bot. Hamburg
6: 351. 1927, not Gilg ex Engler (1921).
Herbs, rhizomatous. Rhizomes elongate, 5–8 mm in diam.
Stems short. Leaves mostly basal; stipules caducous; petiole
13–26 cm, rusty villous; blade broadly ovate to oblong, slightly
asymmetric, 10–20 × 9–19(–21) cm, sparsely pubescent, venation
palmate, 6(–8)-veined, base slightly obliquely cordate,
margin remotely serrate, distinctly lobed, divided to ca. 1/2 of
leaf length; lobes caudate-acuminate at apex; lobules present.
Inflorescences 17–27 cm tall, sparsely rusty villous; bracts oblong-ovate,
4–5 mm, villous, apex acute. Staminate flowers:
pedicel 4–4.5 cm; tepals 4, pinkish, outer 2 broadly ovate, 2–2.7
cm, outside villous, inner 2 obovate-oblong, 2–2.6 × ca. 1 mm;
stamens numerous; filaments fused at base; anthers oval. Pistillate
flowers: pedicel 4–5 cm; ovary oblong, ca. 10 × 5 mm, glabrous;
placentae axile, bilamellate; tepals 5, unequal, obovate to
broadly ovate, 2–2.5 × 0.7–2.2 cm, outside villous; styles 2,
fused to halfway; stigmas 2-cleft, spiraled. Capsule nodding, ca.
1.2 × 9 mm, unequally 3-winged; abaxial wing larger, triangular.
Fl. Jul–Aug.
● Forests or scrubby vegetation, moist environments by streams;
300–800 m. Jiangxi.
Very similar to Begonia pedatifida, this species can only be distinguished
by its shallowly divided leaves and cordate leaf bases.
4. Begonia alveolata T. T. Yu, Bull. Fan Mem. Inst. Biol., n.s.,
1: 121. 1948.
点 叶 秋 海 棠 dian ye qiu hai tang
Begonia pingbienensis C. Y. Wu.
Herbs, erect on upper part, ascending at base. Rhizome absent.
Stems slender. Leaves cauline, asymmetric; stipules ovatelanceolate,
ca. 5 mm, membranous, pilose, apex acute; petiole
3–6 mm, densely villous; blade ovate, asymmetric, 4–6.5 × 3–5
cm, thin when dried, abaxially densely papillose, subglabrous
or sparsely pubescent on veins, villous at junction between
blade and petiole, adaxially sparsely hirsute, venation palmatepinnate,
6-veined, base obliquely cordate, margin irregularly
denticulate, apex acuminate. Inflorescences subglabrous; bracts
caducous, apex acuminate. Staminate flowers: tepals 4, pinkish,
glabrous, outer 2 elliptic or obovate, ca. 12 × 6 mm, inner 2
elliptic, ca. 6 × 2 mm; stamens numerous; filaments free. Pistillate
flowers: tepals 5, subequal, 8–10 × 4–6 mm, glabrous;
ovary 3-loculed, glabrous; placentae axile, bilamellate; styles 3,
free; stigmas 2-cleft, spiraled. Capsules pendulous, unequally 3-
winged; abaxial wing larger, triangular. Fl. Nov.
Forests, moist environments; 1000–1500 m. Yunnan (Pingbian)
[Vietnam].
This species resembles Begonia morifolia but differs by its glabrous
flowers and very shallowly lobed leaves.
5. Begonia arboreta Y. M. Shui, Acta Bot. Yunnan. 24: 307.
2002.
树 生 秋 海 棠 shu sheng qiu hai tang
Herbs, deciduous, epiphytic. Tubers subglobose, ca. 1 cm
in diam. Leaves solitary; stipules caducous, basal, glabrous;
petiole 12–14 cm; blade asymmetric, broadly ovate, 14–15 ×
14–17 cm, papery, venation palmate, 3–5-veined, base obliquely
cordate, margin irregularly repand-denticulate, distinctly
lobed, divided to 3/5 of leaf length; lobes lanceolate, apex acuminate.
Inflorescences 10–12 cm tall, terminal, glabrous; bracts
caducous, ovate, ca. 0.6 × 0.2 mm. Staminate flowers not seen.
Pistillate flowers: pedicel 3–3.3 cm; tepals not seen; ovary glabrous,
3-loculed; placentae axile, bilamellate; styles 3; stigmas
2-cleft. Capsule pendulous, 2–2.4 × 1.2–1.4 cm, subequally 3-
winged; abaxial wing slightly larger, apex subtruncate.
● Evergreen broad-leaved forests, on tree trunks; 1700–1900 m.
Yunnan (Lüchun).
The description of this epiphytic species is based on a single
specimen collected from Lüchun. Begonia arboreta may represent a
diminished form of B. garrettii Craib from Thailand and perhaps does
not warrant the specific status.
6. Begonia asperifolia Irmscher, Mitt. Inst. Allg. Bot. Hamburg
6: 359. 1927.
糙 叶 秋 海 棠 cao ye qiu hai tang
Herbs, deciduous. Tubers subglobose, 1.3–2 cm in diam.
Leaves 1(or 2), basal, occasionally with short stem; stipules caducous;
petiole (8–)15–23(–28) cm, subglabrous or tomentose;
blade broadly ovate, asymmetric, 15–20(–30) × 11–18(–20) cm,
abaxially pubescent, more densely so on veins, or rusty tomentose,
adaxially sparsely pubescent or densely strigose, venation
palmate, 6–8-veined, base slightly oblique, cordate, margin irregularly
serrulate, undivided or very shallowly lobed. Inflorescences
terminal, racemose at base, 12–25 cm tall, subglabrous;
bracts oblong-ovate to ovate, 5–6 × 1–1.2 cm, membranous,
apex obtuse. Staminate flowers: pedicel 1–1.5(–2.5) cm; tepals
4, pink, glabrous, outer 2 suborbicular, 1.1–1.3 × 1–1.2 cm,
inner 2 oblong to ovate-oblong, 8–10 × 5–7 mm; stamens numerous;
filaments free; anthers oblong. Pistillate flowers: pedicel
2–2.5 cm; tepals 5, pink, unequal, obovate to suborbicular,
5–11 × 3–9 mm, glabrous; ovary elliptic, ca. 7 × 5 mm, glabrous,
3-loculed; placentae axile, bilamellate; styles 3, free; stigmas
U-shaped, slightly spiraled. Capsule pendulous, oblong to
obovoid-oblong, unequally 3-winged; abaxial wing triangular or
obliquely so, 1.2–1.4(–1.9) cm; lateral wings 3–4 mm, rarely
absent or reduced to very narrow lamellae. Fl. Aug–Oct, fr.
Sep–Nov.
● Broad-leaved forests, mixed broad-leaved and coniferous forests,
along streams, rocky slopes; (1500–)1800–3400 m. SE Xizang, W
Yunnan.
Similar to Begonia labordei, this species differs by its large, somewhat
rugulose leaves and 5-tepaled pistillate flowers (in B. labordei, the
pistillate flowers have 3(or 4) tepals). Some specimens of intermediate
size and lacking pistillate flowers are difficult to identify.
1a. Leaf blade abaxially pubescent, adaxially
sparsely pubescent; flowers much more
than 1 cm in diam. ................................ 6a. var. asperifolia
1b. Leaf blade abaxially rusty tomentose,
adaxially densely strigose; flowers ca.
1 cm in diam.
2a. Capsule with 3 conspicuous unequal
wings ............................................. 6b. var. tomentosa