Begonia (sect. Platycentrum) palmata D. Don (Don 1825
Creators: name: Camfield, Rebecca
name: Hughes, Mark
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Cucurbitales
Begoniaceae
Begonia
Begonia palmata

description: Begonia palmata D.Don [sect. Platycentrum]
Fig. 45
Prodromus Florae Nepalensis: 223 (Don 1825). – Type: Nepal, 1818, Wallich (lecto-: BM000521518).
Begonia laciniata Roxb., Flora Indica 3: 649 (Roxburgh 1832).
– Type: Nepal, 1821, Wallich Cat. No. 3678b (lecto-: K-W, barcode K001110780, here designated; isolecto-: E00265066).
Citations in other publications
As B. palmata: Hara (1966: 215), Hara (1968: 60), Hara (1971: 84), Hara et al. (1979: 182), Grierson (1991: 245), Chauhan (1996: 176), Chauhan (2000: 425), Kumar (2002: 648), Kress et al. (2003: 171), Gu et al. (2007: 189), Uddin (2007: 594), Hughes (2008: 94), Peng & Ku (2009: 241), Morris (2010d: 138), Dash (2010: 38), Verma et al. (2013: 179), Baruah & Choudbury (2014: 41); as B. laciniata: de Candolle (1864: 347), Clarke (1879: 645), Clarke (1881: 119), Clarke (1890: 25), Koorders (1912: 645), Gagnepain (1921: 1107), Burkill (1924: 287), Craib (1931: 775), Kanjilal (1938: 334), Fischer (1938: 98), Deb (1961: 285), Kress et al. (2003: 171), Khatun (2008: 9).
Description
Rhizomatous, erect, monoecious herb, 45–100 cm high. Rhizome: 5–15 mm wide, sparsely to densely tomentose, internodes 1–3 cm long. Stem: stout, 5–15 mm wide, sparsely to densely tomentose to villose, internodes 5–13(–20) cm long. Stipules: lanceolate to broadly lanceolate, 10 –30 × 3–10 mm, glabrous to villose on main vein, semi persistent to persistent. Leaves: petiole 1.5–19 cm long, densely tomentose to sparsely puberulous, lamina narrowly to broadly ovate, to almost orbicular, basifixed, base truncate, or base cordate to shallowly cordate, lobes not overlapping, 5–20 × 2–20 cm, strongly asymmetric to slightly asymmetric, upper surface green, or green with pale ring marking, hirsute to strigose all over denser on veins or hairs on veins only, or verrucose, underside green or reddish, pubescent to pilose all over being denser on veins or on veins only; venation palmate, midrib 3.5–18 cm long: margin broadly lobed-dentate with fine serration to deeply scalloped between veins with fine serrations; with several lobes, short to long, wide to narrow, triangular, curved or not curved, acuminate or acute, with sparse short hairs to glabrous; apex acute to acuminate. Inflorescence: cymose, axillary to terminal, few; peduncle tomentose, branching 2–3 times, primary 7–15(–20) cm, secondary 0.5–2 cm, tertiary 1–5 mm long, with 2– 6 female and 2– 6 male flowers; bracts lanceolate or sub-orbicular or triangular, 6–17 × 3–13 mm, margin with hairs or glabrous, deciduous or persistent. Male flower: pedicel 8–30 mm long, glabrous or densely to sparsely tomentose; tepals 4; outer tepals obovate or ovate or orbicular, 8–22 × 4–17 mm, white to pink, tomentose to puberulous on reverse, denser near base, margin entire; inner tepals elliptic or obovate or oblong, 6–15 × 3–8 mm, white to pink, glabrous, entire; androecium with 40–80 stamens, symmetric; filaments 1–3 mm long, unequal, fused at base into a short column; anther oblong elliptic to oblong obovate, 1–1.5 mm long, dehiscing through slits longer than half the length of the anther, not hooded, connective extended. Female flower: pedicel 9–30 mm long, glabrous or densely to sparsely tomentose; bracteoles absent; tepals 5, equal, elliptic-ovate, outer tepals 10 –15 × 7–10 mm, white to pale pink, glabrous or tomentose to puberulous on reverse, denser near base, margin entire, inner tepals similar yet smaller and glabrous; ovary 2-locular, placentae bifid, capsule oblong-ellipsoid, 6–8 × 4–5 mm, tomentose, with one long oblong wing and two short rounded wings; styles 2, forked once and twisted twice, persistent. Fruit: recurved 10–18 × 12–34 mm; capsule oblong-ellipsoid, 7–18 × 2–9 mm, glabrous or sparsely tomentose all over or just at base of wings; wings sometimes extending along the pedicel slightly, unequal; longest wing triangular to rounded oblong, 9–20 × 3–13 mm; shortest wings oblong to half-ovoid, 1–5 × 10–15 mm.
Distribution and phenology
Northeast India; also in China, Nepal, Sikkim, Bhutan, Bangladesh, Myanmar, Thailand, Laos and Vietnam; 200–2150 m. Flowering: April to October; fruiting: May to November.
Conservation status
Least Concern (Hughes 2008). Begonia palmata is a very widespread species found throughout eastern Asia, with no significant change in recent years to warrant a change in its status.
Key to varieties
1. Stem petioles and peduncles sparsely to densely short brown tomentose, leaves with curved lobes, upper surface hirsute......................................................................... B. palmata D.Don var. palmata
– Stem petioles and peduncles densely long red villose, leaves with straight triangular lobes, and upper surface verruculose ........................... B. palmata D.Don var. khasiana (Irmsch.) Golding & Kareg.
description: Published as part of Camfield, Rebecca & Hughes, Mark, 2018, A revision and one new species of Begonia L. (Begoniaceae, Cucurbitales) in Northeast India, pp. 1-116 in European Journal of Taxonomy 396 on pages 70-71, DOI: 10.5852/ejt.2018.396, http://zenodo.org/record/3787049