Begonia ovatifolia, : de Candolle, 1864

Camfield, Rebecca & Hughes, Mark, 2018, A revision and one new species of Begonia L. (Begoniaceae, Cucurbitales) in Northeast India, European Journal of Taxonomy 396, pp. 1-116 : 67-70

Begonia ovatifolia A.DC. [sect. Diploclinium ]

Figs 43–44

Annales des Sciences Naturelles; Botanique, Sér. 4, 11: 132 (de Candolle 1859). – Type: India, Meghalaya, Khasia, Bev Pauree, 16 Jul. 1850, Hooker & Thomson 27 (lecto-: K, here designated).

Begonia ovatifolia var. cretacea C.B.Clarke, The Flora of British India 2: 643 ( Clarke 1879). – Type: Bhutan, Griffith 2583 (lecto-: K000761422, here designated).

Begonia subovata Wall., A numerical list of dried specimens of plants in the East India Company’s Museum: 129, 3683 ( Wallich 1831), nom. nud.

Citations in other publications

As B. ovatifolia: de Candolle (1864: 328) , Clarke (1879: 642), Clarke (1881: 118), Hara et al. (1979: 182), Grierson (1991: 241), Hynniewta (1994: 183), Uddin (2007: 594), Dash (2010: 38), Morris (2012a: 9); as B. subovata: Clarke (1879: 642) , Golding (1978: 15).

Other material

INDIA: Arunachal-Pradesh: Kapu to Gelling, Choudhery 18053 ( ARUN n.v.). Meghalaya: Garo Hills, Tura Mountain, Dec. 1929, Parry 731 ( K); Khasi Hills, Cherrapunji, 10 Aug. 1850, Hooker & Thomson 27 (syn K); ibid., 16 Aug. 1850, Hooker & Thomson 27 (syn K); ibid., 26 Jul. 1952, Koelz 30838 ( MICH); Khasi Hills, Mawphlang, 24 Sep. 1886, Clarke 45107A ( K); ibid., Clarke 45107D ( BM); Khasia, 1 Oct. 1855 – 30 Oct. 1855, s.n. ( E); ibid., Hooker & Thomson 33 ( BM, E 00300439); ibid., Hooker & Thomson s.n. (syn P); ibid., Griffith s.n. ( K 000761423); Sillet Hills, 1821, Wallich Cat. No. 3683 (K-W n.v.). Nagaland: Zekera, 31 Aug. 1935, Bor 6227 ( K).

Description

Tuberous, monoecious herb, 10–20 cm high. Stipules: lanceolate, ca 3 × 1 mm, glabrous, deciduous. Leaves: petiole 5–12 cm long, glabrous or sparsely puberulent; lamina ovate to broadly ovate, basifixed, base shallowly cordate or rounded, 3–10.5 × 2.5–8 cm, slightly asymmetric to symmetric, upper surface green, glabrous or puberulous on veins near petiole attachment, underside green or green and red, sparsely puberulous on veins mostly, venation palmate-pinnate, midrib 3–10 cm long; margin shallowly dentate-denticulate, with very sparse short hairs; apex shortly acuminate. Inflorescence: cymose, axillary or terminal, few; peduncle glabrous, branching 2–3 times, primary 3–7 cm, secondary 1–4 cm, tertiary 3–5 mm, with 4– 5 female and 4– 8 male flowers; bracts lanceolate, 2–3 × 1 mm, glabrous, persistent. Male flower: pedicel 2–10 mm long, glabrous; tepals 4; outer tepals broadly ovate to ovate-orbicular, 2–7 × 2–6 mm, deep pink to white, glabrous, margin entire; inner tepals spathulate to narrowly elliptic, 2–6 × 1–4 mm, white to pink, glabrous; androecium with 10–20 stamens, symmetric; filaments 0.5 mm long, fused at base into a short column; anther oblong-obovate, 0.5–1 mm long, dehiscing through slits about half the length of the anther, not hooded, connective extended, with the apical few stamens being larger and having a broader connective. Female flower: pedicel 4–6 mm long, glabrous; bracteoles absent; tepals 2–4, unequal, obovate-orbicular, outer tepals 5–7 × 3–7 mm, white to pink, glabrous, margin entire, inner tepals as in male flowers; ovary 3-locular, placentae bifid; capsule ellipsoid, 2–4 × 1–1.5 mm, glabrous, with three unequal triangular wings; styles 3, forked once and twisted once, persistent. Fruit: pendulous; capsule ellipsoid, 7–12 × 2–7 mm, glabrous; wings extending along the pedicel slightly, unequal; longest wing triangular with curved edge, 8–15 × 4–11 mm; shortest wings triangular with one curved edged, 3–9 × 5–8 mm.

Distribution and phenology

Arunachal-Pradesh, Meghalaya and Nagaland; also in Nepal, Sikkim and Bhutan; 350–1400 m. Flowering: July to October; fruiting: August to October.

Conservation status

Least Concern. Begonia ovatifolia has an AOO of 52 km 2 and an EOO of 220,700 km 2 with suitable habitat through its range in the eastern Himalayas. The population in the Khasi Hills is at risk due to deforestation but there is hope due to several national parks within the hills and reserved forests, such as the Cherrapunji-Mawsynram Reserved Forest.

Remarks

Begonia ovatifolia is allied to B. labordei and B. adscendens but the leaves are smaller and more symmetric than either of those species. The minute flowers of B. ovatifolia are characteristic, with glabrous tepals ca 5 mm long, unlike those of B. adscendens and B. labordei which are ca 10 mm long with hairs present on the outer surface. The variety B. ovatifolia var. cretaceae C.B.Clarke has types from Bhutan (Griffith herb. no. 2583, K) and Khasia, collected by Clarke from Churra (Cherrapunji); the latter has not been located.