Ceropegia stenantha K.Schum.

Apocynaceae (part 2), David Goyder, Timothy Harris, Siro Masinde, Ulrich Meve, Johan Venter. Flora of Tropical East Africa, 2012

Morphology General Habit

Glabrous twiner to 2 m high.

Morphology General Exudate

Latex milky.

Morphology Roots

Root system a cluster of whitish fusiform roots, up to 12 cm long × ± 5 mm thick, arising laterally for ± 5 cm off the main vertical rootstock.

Morphology Stem

Stem mostly sparsely branched, occasionally much branched from near base to form a dense bush to 30 cm wide, vaguely angular, succulent, 2–5 mm diameter, greenish, often with some greyish, or grey-maroon streaks

Morphology Leaves

Leaves subsucculent to succulent; petiole 0–4 mm long; lamina narrowly or broadly linear or linear-elliptic, (5–)20–60(–160) × 2–10 mm, base cuneate, apex acute, glabrous on both sides, margin ciliolate

Morphology Reproductive morphology Inflorescences

Inflorescence extra-axillary, umbellate, usually dense at or near almost every successive node, sublateral at nodes, 1–10-flowered, flowers developing successively with up to several flowers open at a time, without detectable scent, subsessile to shortly pedunculate; peduncle 0–4 mm long, ± 1.5 mm diameter.

Morphology Reproductive morphology Inflorescences Bracts

Bracts linear-subulate, ± 1–2 × 0.3 mm, maroon or pale green with purplish speckling.

Morphology Reproductive morphology Flowers Pedicel

Pedicels 3–10 mm long

Morphology Reproductive morphology Flowers Calyx

Sepals subulate, 2–3 × 0.5–1 mm wide at base, apex recurved, pale green with maroonish apex or spotted purplish-maroon

Morphology Reproductive morphology Flowers Corolla

Corolla 20–30(–35) mm long; tube 10–20 mm long, in basal 1/4– 1/3 or more with elongated ovoid inflation 4–8 × 2–3 mm, narrowing gradually into a long ascending cylindrical part ± 2 mm diameter, not dilated in throat; exterior creamy-white, greenishwhite/yellow or yellowish, glabrous; lobes linear, (6–)15–17 × 0.5–1 mm, not completely folded back, margins gently recurved, with conspicuous basal horn-like auricles below sinuses of adjacent lobes, connate at apices to form an elliptical cage; glabrous, pale yellow-green to creamy-white, sometimes purplish or maroon at connate apices. Corona shortly stipitate, 2.5 × 1.3–1.6 mm diameter, mostly translucent white; outer lobes apically much reduced, forming five shallow pouches ± 0.5 mm deep, apex truncate, entire; inner lobes 1.5 × 0.2 mm, cylindrical, erect, free, apically recurved, apex rounded

Morphology Reproductive morphology Flowers Pollinia

Pollinia 0.3–0.36 × 0.2–0.27 mm; corpusculum linear-obovate, 0.11–0.14 × 0.05 mm at centre, brownish-orange

Morphology Reproductive morphology Fruits

Follicles paired, acutely divergent (45–)60–100 mm long × ± 3 mm at centre, at maturity green to yellow green with maroon streaks; seed dark brown, 6–7 × 1.5–2 mm, with a marginal wing; coma 20–30 mm long.

Ecology

Thickets in grassland and open woodland; 500–1300(–1900) m

Note

C. stenantha is related to C. yampwapwa and probably distantly related to C. nilotica. The specimen Polhill & Paulo 1353 from Tanzania is unusual by its very short corolla lobes in relation to the tube and the fine longitudinal ridges inside the inflation.

Distribution

Flora districts: U2 U4 K4 K6 T1 T2 T3 T4 T5 T6 T7 T8 Range: Congo-Kinshasa, Rwanda, South Sudan, Zambia, Malawi, Mozambique, Zimbabwe, Namibia, South Africa

Goyder, D. J., Gilbert, M. G. & Venter, H. J. T. (2020). Apocynaceae (part 2). In: M. A. García (ed.), Flora Zambesiaca, Vol. 7(3). Royal Botanic Gardens, Kew.

Type

South Sudan, Bahr el Ghazal, Djur Ghattas, Schweinfurth 2104 (B† holotype, K lectotype), designated by Huber in Mem. Soc. Brot. 12: 125 (1958); (K000305521 lectotype, K000305522, MEL710747) second step lectotype designated here.

Morphology Roots

Roots clustered, fleshy, fusiform, up to 15 cm long, c.5 mm thick

Vegetative Multiplication Tubers

Tuber absent

Morphology Stem

Stem twining or sometimes trailing, branched, succulent, up to 8 meters long, 2–5 mm thick, glabrous

Morphology Leaves

Leaves succulent; petiole (0)2–8 mm long, glabrous; leaf blade lanceolate to linear, 25–150 × 2–18 mm, base and apex tapering, margin sometimes ciliolate, midrib abaxially prominent, both surfaces glabrous

Morphology Reproductive morphology Inflorescences

Inflorescences often many, extra-axillary, peduncle (0)3–12 mm long; cyme umbel-like, 3–8(10)-flowered, up to 4 flowers open at once

Morphology Reproductive morphology Flowers Pedicel

Pedicel 1–5(10) mm long, glabrous

Morphology Reproductive morphology Flowers Calyx

Sepals subulate, mottled purple or with purplish tip, 2–3 × 0.5–1 mm wide, glabrous

Morphology General Buds

Bud with minutely recurved sinuses and linear-oblong beak

Morphology Reproductive morphology Flowers Corolla

Corolla 20–30(35) mm long, straight to slightly curved; tube 10–20 mm long, basal chamber cylindrical-inflated, 4–8 mm long, 2–3 mm wide, narrowed above, not dilated at mouth, exterior pale yellow, cream or white, often greenish, rarely pinkish, glabrous, interior blotched purple at base, thinly pilose with fine hairs inside at base and middle of tube; sinuses acute, narrowly but distinctly auriculate; lobes linear, 10–20 mm long, ± as long as tube, somewhat revolute, apices usually connate to form narrowly ellipsoid to fusiform cage with acute apex, some lobes occasionally becoming detached at their tip, abaxially pale, both surfaces glabrous, adaxially pale, rarely brighter, yellow, sometimes darker at tip

Morphology Reproductive morphology Flowers Corona

Corona stipitate, outer lobes forming very shallow pouches, laterally confluent with base of inner lobes; truncate, inner lobes incumbent-erect, linear-lanceolate or linear- oblong, c.1.5 mm long, apices obtuse, sometimes recurved

Morphology Reproductive morphology Seeds

Seed dark brown, 6–7 × 1.5–2 mm wide; coma 20–30 mm long. Follicles erect, narrowly divergent, linear-fusiform, (4.5)9–11 × 0.2–0.3 cm wide at middle, glabrous

Distribution

Botswana, Zambia, Zimbabwe, Malawi, Mozambique. Also in Namibia, South Africa, D.R. Congo, Rwanda, Tanzania, Kenya, Uganda and South Sudan.

Ecology

On rock outcrops, in Colophospermum mopane, Brachystegia or riverine woodland, on sandy, loamy or clay soils, often associated with termite mounds, often in shade; 40–1650 m.

Conservation

LC. The most frequently collected member of the genus in the Flora area.