Begonia kisuluana Büttner

Begoniaceae, Vanessa Plana, Martin J.S. Sands & Henk J. Beentje. Flora of Tropical East Africa. 2006

Type

Type: Angola, Arthington Falls near Kisulu, three days journey from San Salvador, Büttner 496 (B, lecto.).

Habit

Epiphytic herb or soft-wooded shrub with stems to 1(–2) m long; stems erect, up to 6 mm thick, branched, rooting at the nodes, woody at the base; indumentum of peltate scales with fimbriate margins. Stipules narrowly triangular, 1–2.5 cm long, caducous, boat-shaped, not curved, apex acuminate, hairy on outside.

Leaves

Leaves leathery, drying thin, weakly asymmetrical, ovate to elliptic, sometimes narrowly elliptic, 2–12 × 0.8–6.2 cm, base obliquely cordate to rounded or truncate, margin entire, rarely obscurely denticulate towards the apex, apex commonly broadly acute to obtuse, rarely acuminate, glabrescent above and below, with a few scattered lepidote hairs; venation pinnate; petiole 0.4–2.2(–6) cm long.

Inflorescences

Female inflorescence with 1–3 flowers, peduncle 1–5 mm long; bracts similar to those in male inflorescence but up to 8 mm long; pedicel to 2 mm long. Inflorescence axillary, a unisexual dichasial cyme. Male inflorescence with up to 15 flowers, peduncle (0.4–)0.8–2.8(–3.5) cm long; each ramification subtended by a pair of opposite bracts 3–7 mm long, smaller in the upper parts of the inflorescence, chartaceous, almost connate; pedicels 0.4–1.2 cm long; bracteoles absent.

Flowers

Female flowers: subsessile, tepals 4, free, shape and colour similar to male flowers, the outer 6–12 × 3–5.5 mm, the inner 4–10 × 1.5–3 mm; ovary fusiform, without wings, 3-locular; placentation parietal through less than 40% of the ovary, the rest septal; styles 3, simple at the apex (1 flower observed to have forked style), glabrous, not persistent in fruit; stigma yellow, simple. Male flowers: tepals 4, free, white suffused with pink on the upper half, the outer obovate, 5–8 × 3–5.5 mm, the inner narrowly obovate, 3.5–8 x 1–3 mm; stamens 10–19, filaments fused 0.8–1.5 mm from the base; anthers narrowly ellipsoid to obovoid, 0.8–1.5 mm long, apex obtuse to acute.

Fruits

Fruits fleshy, fusiform, often somewhat curved, 1.2–3.5 cm long, 0.3–0.4 cm in diameter, terete in cross section, greenish-yellow, dotted with lenticels, dehiscent by a lateral longitudinal slit.

Ecology

Swampy river valleys within forest; altitude not given, presumably around 700–1300 m .

Conservation

Least concern (LC); widespread .

Note

Although the species is described as possessing simple, unforked styles, a single flower from Katende K2765 has forked styles with a long horseshoe-shaped stigma, almost identical to those in B. eminii. This however, appears to be an aberrant flower; the other flower on the same inflorescence has typical B. kisuluana styles.

Distribution

Range: Nigeria, Cameroon, Gabon, Congo-Brazzaville, Congo-Kinshasa, Angola Flora districts: U2