Agelanthus zizyphifolius (Engl.) Polhill & Wiens

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation

Predicted extinction risk: not threatened. Confidence: confident

Flora Zambesiaca. Vol. 9, Part 3. Polygonaceae-Myriaceae. Pope GV, Polhill RM, Martins ES. 2006.

Type

Type:from Tanzania. Type from Tanzania.

Morphology Leaves

Leaves alternate to subopposite, rather densely set; petiole 1–2(5) mm long; lamina leathery to rather thick and brittle, dull yellowish-green, 2.5–10(15) × 1–4(4.5) cm, oblong-oblanceolate to oblong-obovate or elliptic, obtuse to shortly rounded at apex, attenuate at base, glabrous or some hairs towards margins and base, 3(5)-nerved from a little above base Leaves alternate to subopposite, rather densely set; petiole 1–2(5) mm long; lamina leathery to rather thick and brittle, dull yellowish-green, 2.5–10(15) × 1–4(4.5) cm, oblong-oblanceolate to oblong-obovate or elliptic, obtuse to shortly rounded at apex, attenuate at base, glabrous or some hairs towards margins and base, 3(5)-nerved from a little above base.

Morphology Reproductive morphology Flowers

Flowers clustered in axils or at old nodes; pedicels 0–3 mm long; bract 3–4 mm long, cupular with a small triangular limb, ciliolate and sometimes puberulous Flowers clustered in axils or at old nodes; pedicels 0–3 mm long; bract 3–4 mm long, cupular with a small triangular limb, ciliolate and sometimes puberulous.

Morphology Reproductive morphology Flowers Receptacle

Receptacle 1.5 mm long; calyx 3–5 mm long, tubular, shortly to distinctly toothed, ciliolate Receptacle 1.5 mm long.

Morphology Reproductive morphology Flowers Corolla

Corolla 3–4.5 cm long, pink below, sometimes with a green or red band at top of tube, whitish over vents, with red tips to lobes; apical swelling of bud slight, 4–5 × 1.5–2 mm, oblong to oblong-fusiform; basal swelling 4–7 × 2–4 mm, with tube narrowly constricted for 3–4 mm above; lobes erect, 8–9 mm long, with upper three-eighths to two-thirds linear-oblanceolate, pointed, slightly keeled and hardened inside Corolla 3–4.5 cm long, pink below, sometimes with a green or red band at top of tube, whitish over vents, with red tips to lobes; apical swelling of bud slight, 4–5 × 1.5–2 mm, oblong to oblong-fusiform; basal swelling 4–7 × 2–4 mm, with tube narrowly constricted for 3–4 mm above; lobes erect, 8–9 mm long, with upper three-eighths to two-thirds linear-oblanceolate, pointed, slightly keeled and hardened inside.

Morphology Reproductive morphology Flowers Androecium Stamens

Stamen filaments red to purple, inflexed to involute, slightly tapered, corrugated, last 0.5–0.8 mm paler, smooth, hardened; anthers 2–2.5 mm long Stamen filaments red to purple, inflexed to involute, slightly tapered, corrugated, last 0.5–0.8 mm paler, smooth, hardened; anthers 2–2.5 mm long.

Morphology Reproductive morphology Flowers Gynoecium Style

Style green or whitish, slender to slightly winged opposite filaments (then with a slight neck below stigma); stigma 0.7–0.8 mm across, ovoid-conic. Berry red, 8 × 7 mm, ellipsoid-obovoid, with persistent calyx; seed pink or yellow.

Note

The northern populations are conspicuously hairy, the southern populations, formerly referred to Loranthus vittatus, are glabrous or almost so, with the central Tanzanian plants (including the type) intermediate, with rather sparse indumentum. The montane forest form from Mbulu to the Nyika Plateau differs from subsp. zizyphifolius of Kenya and northern Tanzania essentially only in the lack of hairs, but from southern Tanzania southwards the subspecies descends along rivers into the plateaux, very commonly found on Syzygium. This form tends to have shortly pedicellate (rather than sessile) flowers and the style tends to be slightly winged opposite the filaments creating a slight neck below the stigma. In the Mbala-Kasama region of northern Zambia the calyx is markedly lobed. In northern Zimbabwe, around the Great Dyke, the species is adapted to wooded grassland and common on Diplorhynchus; the seeds of this form are yellow, not pink as seen in northern Malawi. There is clearly some incipient divergence, but, on present evidence, insufficient to warrant formal taxonomic recognition.

Morphology Branches

Branchlets and leaves glabrous.

Ecology

Montane and riverine forest, extending marginally into adjacent miombo woodland and in Zimbabwe into wooded grassland; 500–2200 m; commonly on Syzygium, sometimes on other forest trees, in Zimbabwe commonly on Diplorhynchus; found flowering in most months, but with the main flush during the rains.

Distribution

Eastern Rift from Mbulu in northern Tanzania, south to central Zimbabwe and westwards into Katanga (Shaba) Province of Dem. Rep. Congo. Flanks and adjacent plateaux of eastern Rift Valley from central Kenya to central Zimbabwe, extending west to Burundi, Katanga (Shaba) Province of Dem. Rep. Congo, and Zambia. Mozambique Malawi Zimbabwe ZAM N, ZAM W, ZAM C, ZAM E, ZAM S, ZIM N, ZIM C, MAL N, MAL C, MOZ N Zambia

Morphology General Habit

Shrub extending to 40–100 cm or so; branchlets slightly compressed to 4-angular, then terete, glabrous to red-brown tomentose. Shrub extending to 40–100 cm or so; branchlets slightly compressed to 4-angular, then terete, glabrous to red-brown tomentose

Morphology Reproductive morphology Flowers Calyx

Calyx 3–5 mm long, tubular, shortly to distinctly toothed, ciliolate.

Morphology Reproductive morphology Flowers Gynoecium Pistil

Style green or whitish, slender to slightly winged opposite filaments (then with a slight neck below stigma); stigma 0.7–0.8 mm across, ovoid-conic.

Morphology Reproductive morphology Fruits

Berry red, 8 × 7 mm, ellipsoid-obovoid, with persistent calyx; seed pink or yellow.