Begonia medogensis Li et al. (2018: 14)

Taram, Momang, Borah, Dipankar & Hughes, Mark, 2023, Two new records of Begonia for the flora of India from Arunachal Pradesh, Phytotaxa 584 (2), pp. 115-120 : 116-119

Begonia medogensis Li et al. (2018: 14) ( Fig. 3 )

Type:— CHINA. Tibet, Medog County, Xiaohua Jin, Jianwu Li, Xilong Wang & Chengwang Wang 19331 (holotype: HITBC!, isotype: HITBC!, PE!, K!). Figure 2A–I and 3 .

Perennial monoecious herbs, caulescent, erect. Rhizomes short, stout. Stems reddish-purple, floccose, 50–150 cm tall, internode 6–15 cm long, upper part well-branched, with internodes 2–5 cm long. Stipules persistent, triangular to lanceolate, 6–8 × 1.5–2.5 mm, apex acuminate to cuspidate. Leaves cauline; petiole 1.2–2.7 cm long, floccose; leaf blade ovate-lanceolate, slightly asymmetric, 6–10 × 2–3.7 cm, adaxially green, slightly hairy, abaxially greenishwhite, hairs prominent on veins, venation palmate-pinnate, 5–8-veined, base slightly oblique, rounded to sub cordate, margins remotely and irregularly denticulate, apex caudate-acuminate. Inflorescences axillary to terminal cymes, to 6 cm, sub-pendulous, primary peduncles 2.7–4 cm long, secondary peduncles 0.5–1.0 cm long, terminally with 1–5 flowers; floral bracts lanceolate to ovate-lanceolate, 5–10 × 1.7–5 mm, thickly papery, glabrous, apex acuminate. Staminate flowers: pedicel 1.5–2.5 cm long, glabrous; tepals 4, white, outer 2 broadly ovate to orbicular, 1.8–2.3 × 1.3–1.7 cm, tinted with pink, glabrous, apex rounded; inner 2 elliptic to ovate, 1.6–2.1 × 0.7–0.9 cm, glabrous, apex obtuse to rounded; stamens 60–80; filaments free, c. 2 mm long, sub-equal, fused at base into a 4–6 mm diameter column; anthers obovate, c. 1 mm long, apex emarginated. Pistillate flowers: pedicel 0.9–2 cm long, tepals 5, pinkish white, unequal, glabrous, outer broadly ovate, 1–1.4 × 0.8–1.2 cm, apex rounded, inner tepals smaller, elliptic-ovate, 9–13 × 5–9 mm, apex rounded; ovary glabrous, 2-loculed; placentae axile, bi-lamellate; styles 2, fused at base; stigmas 2-cleft, spiralled. Capsule sub-pendulous, cylindroid, 8–15 × 10–23 mm; wings 3, central 1 larger, oblong, 7–15 × 10–15 mm, apex truncate, lateral 2 less developed, 3–5 × 10–15 mm.

Flowering and Fruiting:― March–August and October–December.

Distribution:― China (Tibet), Myanmar ( Chen et al. 2018; Li et al. 2018) and India (present study).

Habitat and Ecology:― It is found along the forest floor near annual streams, where stone banks remain moist throughout the year at an elevation from 800–1200 m. It was found in association with Piper pedicellatum C.DC. , Hydrocotyle javanica Thunb., Musa sp., Thladiantha cordifolia (Blume) Cogn. , Impatiens arguta Hook.f. & Thomson , etc. along with mosses, liverworts and ferns.

Specimen examined:― INDIA. Arunachal Pradesh: Lower Subansiri District, near Potin to Kimin road, 980 m, 21 March 2022, Momang Taram & D.Borah 9547 Herbarium of Rajiv Gandhi University , Arunachal Pradesh.

Figures

FIGURE 2. Begonia asperifolia Irmsch. a, b. habit, c. adaxial leaf surface, d. abaxial leaf, e, f. outer and inner surface of stipules, g. bracts, h. inflorescence, i, j. male flower, k, l. stamens, m, o. female flower, p. cross section of ovary, q, r. capsule.

FIGURE 3. Begonia medogensis Li et al.: a–c: Habit, b–c. flowering stem, d. abaxial surface of a leaf, e. tender shoots with stipules, f. flowering buds, g–i. inflorescences, j. bracts, k. staminate flower, l. stamens, m. pistillate flower, n. ovary, o. tepals, p. capsule, q. cross section of capsule.