Anisosepalum humbertii (Mildbr.) E.Hossain

J. R. Timberlake, E. S. Martins (2013). Flora Zambesiaca, Vol 8 (5) Acanthaceae Part 1. Royal Botanic Gardens, Kew

Morphology General Habit

Erect, scandent or sprawling perennial or shrubby herb, sometimes forming large bushes or tangles; stems often purplish, up to 1.5(2) m long, with a long transverse band of hairs at upper nodes, otherwise glabrous or with scattered hairs, rarely with a longitudinal band of hairs on upper node or uniformly puberulous

Morphology Leaves

Leaves glabrous to sparsely crisped puberulous, densest along veins; petiole to 3(4) cm long, pubescent; lamina ovate to elliptic, abruptly narrowed to a decurrent attenuate base, largest (5)8–17 × (2)3–6 cm; apex acute to acuminate with acute or obtuse tip; margin entire to grossly crenate-dentate

Morphology Reproductive morphology Inflorescences

Raceme dense and subcapitate in flower, much elongated in fruit, often purplish tinged, 1–20 cm long, axis glabrous to puberulous; peduncle 0–3(6) cm long, indumentum as stem; bracts lanceolate, oblanceolate or narrowly elliptic, 11–20 mm long, crisped puberulous on midrib and ciliate, with scattered peltate glands; pedicels 1–3 mm long, glabrous or puberulous; bracteoles linear-lanceolate, 7–16 mm long, crisped ciliate

Morphology Reproductive morphology Flowers Calyx

Dorsal and two ventral sepals linear-lanceolate, 8–15 mm long, ciliate, lateral sepals similar or narrowly triangular, 2–6 mm long

Morphology Reproductive morphology Flowers Corolla

Corolla pink, pale mauve to mauve, lilac, violet or blue, with 4 white bosses on lower lip, 2–3.1 cm long, glabrous outside; tube white, 1.2–1.8 cm long, campanulate above, puberulous inside with band of hairs 5–7 mm above base; upper lip hooded or flat, entire or emarginate, 8–16 mm long; lateral lobes of lower lip spreading or deflexed, oblong-obovate, 6–11 mm long, median lobe deflexed, broadly elliptic to circular, 6–12 mm long

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens held under upper lip; filaments 7–12 mm long, glabrous or minutely puberulous near base; anthers c.1.5 mm long, crisped puberulous; basal part of style puberulous

Morphology Reproductive morphology Fruits

Capsule 8–13 mm long

Morphology Reproductive morphology Seeds

Seed pyriform, reticulate, 1.5–2 mm long.

Distribution

Zambia. Also in Congo.

Ecology

Riverine forest and swamp forest (mushitu), riverine woodland; 1350–1800 m.

Conservation

Not threatened.

Recognition

Subsp. humbertii from Congo, Uganda, Rwanda, Burundi and Tanzania has a shorter corolla tube with the band of hairs closer to the base.

Acanthaceae (part 1), Kaj Vollesen, Flora of Tropical East Africa, 2008

Morphology Reproductive morphology Inflorescences

Racemes dense and subcapitate in flower, elongating in fruit, 1–6 cm long; axes glabrous to puberulous; peduncle 0–1(–1.5) cm long, glabrous; bracts oblanceolate or narrowly so, 8–15 mm long, puberulous on midrib and ciliate, ± scattered peltate glands; pedicel 0.5–1(–2) mm long, glabrous or puberulous; bracteoles linear-lanceolate, 9–13 mm long, crisped-ciliate.

Morphology Reproductive morphology Flowers Calyx

Dorsal and two ventral sepals linear-lanceolate, 9–12 mm long, ciliate, lateral sepals similar or narrowly triangular, 1.5–4 mm long.

Morphology Reproductive morphology Flowers Corolla

Corolla dark blue, bluish violet, purple or dark purple, with 4 white bosses on lower lip, 2–3.3 cm long, glabrous outside; tube 1.6–2 cm long, campanulate above, glabrous inside but for band of hairs 3–4 mm above base; upper lip hooded or ± flat, entire or emarginate, 6–15 mm long; lateral lobes of lower lip spreading, obovate-spathulate, 5–10 mm long, median lobe deflexed, broadly oblong, 8–13 mm long.

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens held under upper lip; filaments 8–20 mm long, glabrous; anthers ± 1.5 mm long, crisped-puberulous; stigma lobes similar.

Morphology Reproductive morphology Fruits

Capsule 8–10 mm long.

Morphology Reproductive morphology Seeds

Seed pyriform, reticulate, 1.5–2 mm long.

Figures

Fig. 4, 10–15.

Morphology General Habit

Shrubby herb or shrub, forming large bushes or ± scandent; stems up to 1.5(–3) m long, with transverse band of hairs at upper nodes, otherwise glabrous.

Morphology Leaves

Leaves opposite; petiole up to 3 cm long, pubescent adaxially; lamina ovate to elliptic, abruptly narrowed into a decurrent base or attenuate, largest 5–11 × 2.5–4 cm, apex acuminate to cuspidate with acute or obtuse tip, margin entire to crenate, subglabrous to crisped-puberulous, densest along veins.