Begonia flaviflora H.Hara [sect. Platycentrum]

Fig. 24

Journal of Japanese Botany 45: 91 (Hara 1970).

– Type: India, Sikkim, Darjeeling, 5 Jul. 1969, Hara, Kurosawa & Ohashi 69218 (holo-: TI n.v.; iso-: BM000839167).

Citations in other publications

Grierson (1991: 245), Gu et al. (2007: 174), Uddin (2007: 593), Hughes (2008: 40), Dash (2010: 33).

Other material

INDIA: Arunachal-Pradesh: Bomte La, 15 Jul. 1938, Ward 13938 (BM); Delei Valley, 16 Jul. 1928, Ward 845 8 (K); Lee to Purchi, Dash 31469 (ARUN n.v.). Nagaland: Naga Hills, Takubama, 1 Sep. 1950, Chand 3614 (MICH); ibid., 12 Aug. 1950, Koelz 25733 (MICH); Samtakha, 6 Aug. 2002, Lyon 15089 (E).

Description

Rhizomatous, erect, monoecious herb, 20–60 cm. Rhizome: ca 5 mm wide, pubescent, internodes 1–3 cm long. Stem: stout, ca 5 mm wide, pubescent, internodes 7–18 cm long. Stipules: broadly lanceolate, 10–15 × 3–5 mm, puberulous, persistent. Leaves: petiole 4–10(–18) cm long, pubescent; lamina ovate, basifixed, base cordate with lobes not overlapping, 5–20(–30) × 5–15(–20) cm, asymmetric, upper surface green with a darker centre, sparsely hispid or glabrous, underside red-purple, pubescent to puberulous mostly on the veins, venation palmate, midrib 4–15(–25) cm long; margin acutely deeply lobed, dentate with finer serration, with sparse hairs; apex acute. Inflorescence: cymose, axillary, several; peduncle pilose, branching up to three times, primary 5–15 cm long, secondary 2–3 cm long and tertiary 4–6 mm long, with 3– 4 female flowers and 2– 3 male flowers; bracts not seen. Male flower: pedicel 20 –30 mm long, pubescent; tepals 4; outer tepals ovate-orbicular, (6–)10–15 × 4–7 mm, yellow, tomentose on reverse, margin entire; inner tepals obovate, 8–12 × 3–4 mm, yellow, glabrous; androecium with 40–60 stamens, symmetric; filaments 1–1.5 mm long, fused at the base; anther ellipticglobose, 1–2 mm long, dehiscing through slits longer than half the length of the anther, not hooded, connective extended. Female flower: pedicel 8–15 mm long, pubescent; bracteoles absent; tepals 5, equal, broadly ovate to oblong, outer tepals 10–13 × 5–10 mm, yellow, tomentose on reverse, margin entire, inner tepals smaller and glabrous; ovary 2-locular, placentae bifid; capsule ellipsoid, tomentose, with one long rounded oblong wing and two short triangular wings; styles 3, deeply forked once and twisted once, persistent. Fruit: recurved; capsule ellipsoid, 5–7 × 4–6 mm, short tomentose; wings extending along the pedicel slightly, unequal; longest round oblong with crenate tip, 6–12 × 2–4 mm; shortest triangular, 1–2 × 3–4 mm.

Distribution and phenology

Arunachal-Pradesh; also in South Tibet, China and Myanmar; 1800–2150 m. Flowering: June to August; fruiting: August.

Conservation status

Least Concern (Hughes 2008), with no significant change in recent years to warrant a change in its status. Begonia flaviflora is a widespread species, and has been recorded in the Gaoligongshan Nature Reserve of China.

Remarks

This species is most similar to B. palmata vegetatively but B. flaviflora has an almost glabrous adaxial leaf surface, shorter stipules and shorter wings on the fruit when compared to B. palmata . When fertile the yellow flowers are instantly distinctive. Begonia xanthina also has yellow flowers, but is distinct in having ovate leaves with an entire margin.