Begonia chemillenensis Moonlight

Moonlight, Peter. W., Jara-Muñoz, Orlando A., Purvis, David A., Delves, Jay, Allen, Josh P. & Reynel, Carlos, 2023, The genus Begonia (Begoniaceae) in Peru, European Journal of Taxonomy 881, pp. 1-334 : 228-230

57. Begonia chemillenensis Moonlight

Figs 71A , 73

Edinburgh Journal of Botany 74 (2): 185 ( Moonlight et al. 2017b).

– Type: PERU – Pasco Region: Prov. Oxapampa • Dist. Palcazú, CC NN, Loma Linda ; 10°22′ S, 75°04′ W; 430 m a.s.l.; 15 Jun. 2010; R. Vásquez, M. Huaman & R. Rivera 36606; holotype: HOXA; isotypes: E [ E00912779 ], MO [ MO-2080522 ], USM.

Etymology

Named for the Chemillén cordillera at the centre of the species’ range.

Selected specimens examined

PERU – Huánuco Region: Prov. Puerto Inca • Dist. Codo de Pozuzo, Route from Pozuzo to Codo de Pozuzo , ca 3.5 km from Puente Paujil; 9°56′50″ S, 75°31′16″ W; 633 m a.s.l.; 20 Feb. 2016; P.W. Moonlight & A. Daza 283; E [ E00833921 ], MOL. – Pasco Region: Prov. Oxapampa • Dist. Pozuzo, Route from Pozuzo to Codo de Pozuzo ; 10°01′05″ S, 75°30′58″ W; 687 m a.s.l.; 20 Feb. 2016; P.W. Moonlight & A. Daza 287; E [ E00833925 ], MOL • Dist. Pozuzo, camino to mirador from Pozuzo ; 10°04′21″ S, 75°32′57″ W; 781 m a.s.l.; 20 Feb. 2016; P.W. Moonlight & A. Daza 274; E [ E00833929 ], MOL • Parque Nacional Yanachaga-Chemillén , Sector Paujil , trail from Pampa Pescado to “las cavernas”; 10°20′32″ S, 75°15′58″ W; 416 m a.s.l.; 25 Feb. 2016; P.W. Moonlight & A. Daza 317; E [ E00833926 ], MOL • Dist. Villa Rica, Route from Villa Rica to Puerto Berudez , km. 88; 10°33′10″ S, 75°05′05″ W; 629 m a.s.l.; 24 Feb. 2016; P.W. Moonlight & A. Daza 313; E [ E00833924 ], MOL.

Description

Caulescent herb, to 40 cm high. Stem erect, unbranched or rarely branching near the base; internodes to 2.5 cm long, to 5 mm thick, flexuous, pale green, glabrous. Stipules persistent, lanceolate, 10–20 × 2–4 mm, apex acuminate, opaque, pale green to brown, glabrous, margin entire, aciliate. Leaves> 5, alternate, basifixed; petiole 3–10 cm long, pale green, glabrous; blade asymmetrical, elliptic to oblanceolate, to 25 × 10 cm, succulent, apex acuminate, base broadly rounded on the broad side of the blade, cuneate to rounded or cordate on the narrow side of the blade, margin irregularly dentate, ciliate, upper surface green, glabrous, lower surface pale green, glabrous, veins palmate-pinnate, 6–8 veined from the base, with 3–5 secondary veins on the larger side, 2–4 secondary veins on the smaller side. Inflorescences 1–3, bisexual, axillary, erect, cymose, with 5 branches, bearing up to 16 staminate flowers and 8 pistillate flowers, protandrous; peduncle to 12 cm long, pale green to red, glabrous, bracts late deciduous, lanceolate, 5–8 × 1–3 mm, translucent, white, pink, or pale green, glabrous, apex acute, margin entire, aciliate. Staminate flowers: pedicels to 20 mm long, glabrous; tepals 4, spreading, outer 2 lanceolate to narrowly ovate, 7–12 × 2–6 mm, apex acute to obtuse, white, occasionally tinged yellow or orange, glabrous, margin entire, aciliate, inner 2 lanceolate to narrowly ovate, 5–11 × 2–3 mm, apex acute, white, occasionally tinged yellow or orange, glabrous, margin entire, aciliate; stamens ca 20, spreading, yellow, filaments 2–3 mm long, attached along the length of a 1 mm long column, anthers broadly obovoid, 0.25–0.5 × 0.25–0.5 mm long, dehiscing via lateral slits, connectives not extended, symmetrically basifixed. Pistillate flowers: pedicels to 15 mm long; bracteoles lacking; tepals 5, subequal, deciduous in fruit, spreading, lanceolate to ovate, 7–8 × 4–5 mm, apex acute to obtuse, white, sometimes tinged yellow, orange or pink, glabrous, margin entire, aciliate; ovary body ellipsoid, 10–15 × 4–6 mm, white, glabrous, unequally 3-winged, wings triangular, the largest 15–17 × 5–12 mm, the smallest two 12–15 × 1–5 mm; 3-locular, placentae branches divided, bearing ovules on both surfaces; styles 3, yellow, free, 2–3 mm long, once-divided, stigmatic papillae in a spirally twisted. Fruiting pedicel to 25 mm long. Fruit body ellipsoid, to 20 × 9 mm, drying brown, wings same shape as in ovary, the largest expanding to 25 × 15 mm, the smallest expanding to 20 × 12 mm.

Proposed conservation assessment

Assessed as Least Concern (LC) by Moonlight et al. (2017b).

Identification notes

Begonia chemillenensis is most similar to B. albomaculata (see Identification notes for B. albomaculata above) but may also be confused with B. maynensis . While B. chemillenensis usually has a cuneate leaf base on the narrow side of the leaf blade, it never has a cuneate base on both sides of the blade and is always broadly rounded on the broad side of the blade.

Distribution and ecology

Endemic to Peru and known from Huánuco and Pasco Regions ( Fig. 71A ). Found in Amazonian and lower montane forest at an elevation of 325–1400 m a.s.l. Begonia chemillenensis is typically collected on rocky or mud banks adjacent to watercourses but has also been collected from roadside and trailside banks. The species is usually locally common.

Figures

Fig. 71. Distribution of the maynensis group of Begonia sect. Knesebeckia (Klotzsch) A.DC. in Peru and surrounding countries. A. B. albomaculata C.DC. (red), B. chemillenensis Moonlight (blue) and B. scorpiocaulisMoonlight & Tebbitt (green). B. B. maynensis A.DC. (red). Black lines indicate country borders, grey lines indicate major administrative divisions, blue lines indicate rivers, and shading indicates elevation.

Fig. 73. Begonia chemillenensis Moonlight. A. Habit. B. Branch of infructescence. C. Branch of inflorescence. D. Bract. E. Staminate flower, front view view. F. Stamens, front and side view. G. Pistillate flower, side view. H. Style and stigma, front and back view. Illustration by Claire Banks from I. Huamantupa et al. 11435 (A), P.W. Moonlight & A. Daza 287 (B, F, H), and 317 (C, D, E, G). Reproduced from Moonlight et al. (2017b), with the permission of Edinburgh Journal of Botany.