Costus afer Ker Gawl.

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

Zingiberaceae, J.M. Lock. Flora of Tropical East Africa. 1985

Morphology General Habit

Perennial herb with erect leafy stems 2-4 m. tall.

Morphology Leaves

Leaves elliptic to obovate, 15-35 × 3.5-9.5 cm., apex acuminate, narrowed below to the rounded or subcordate base, the margin sparsely ascending-ciliate, the lamina otherwise usually glabrous but sometimes sparsely appressed pubescent beneath; petiole 4-12 mm. long; ligule coriaceous, green in life, 4-8 mm. long, glabrous; sheaths lightly striate when dry, in life green, often with purple blotches.

Morphology Reproductive morphology Inflorescences

Inflorescences (?always) terminal on the leafy shoots; floral bracts oblong, convex, truncate to rounded at the apex, ± 3.5 × 3 cm., the upper ones rather smaller, green with purple markings, each subtending 2 fully developed flowers; bracteoles boat-shaped, with a thickened rigid keel, pale green with pink markings and with a thin pink scarious margin, ± 2.5 × 0.8 cm.

Morphology Reproductive morphology Flowers Calyx

Calyx funnel-shaped, 1.7-2 cm. long, with 3 triangular teeth 5 mm. long, with a pink scarious margin; calyx-teeth project 2-3 mm. beyond the bracts after anthesis.

Morphology Reproductive morphology Flowers Corolla

Corolla tube ± 2 cm. long, hairy inside; petals white, semi-transparent, oblong-ovate, 3-4 × 1.2-1.4 cm., hooded at apex; labellum broadly triangular, funnel-shaped, ±2.5 cm. long and wide, white, sometimes tinged pink, with a rich orange-yellow central line which extends to the base of the tube.

Morphology Reproductive morphology Flowers Androecium Stamens

Stamen ovate, ± 3 × 1.2 cm., white; anthers 7-8 mm. long.

Note

Mature fruit and seeds not seen.

Habitat

Moist places in forest, and at forest edges; 190-1200 m.

Distribution

tropical Africa westwards to Sierra Leone K7 T1 T4 T7 U4

Zingiberaceae, J.M. Lock. Flora of Tropical East Africa. 1985

Morphology General Habit

Perennial herb with erect leafy stems 1.5-3.5 m. tall.

Morphology Leaves

Leaves elliptic to obovate, 14-31 × 4-10 cm., apex acuminate, narrowed below to the rounded or subcordate base, appressed pubescent on the midrib beneath and ascending pilose on the margins, otherwise glabrous; petiole 3-10 mm. long; ligule coriaceous, 5-12 mm. long, with a marginal fringe of arachnose hairs, and sometimes with a line of hairs partially surrounding the stem at the ligule-base; sheaths striate, glabrous.

Morphology Reproductive morphology Inflorescences

Inflorescences usually terminal on the leafy shoots, but sometimes borne on separate leafless bracteate shoots; floral bracts broadly obovate, strongly convex, rounded to truncate at the apex, 2-2.5 × 1-1.5 cm., each subtending a single flower; bracteole boat-shaped, coriaceous, 1.8-2 × 0.5-0.8 cm.

Morphology Reproductive morphology Flowers Calyx

Calyx tubular, 1.4-1.5 cm. long, the lobes ± 3 mm. long, incurved.

Morphology Reproductive morphology Flowers Corolla

Corolla-tube 1.4-1.7 cm. long, hairy inside; petals white, oblong to obovate, 3-3.2 × 1-1.2 cm., hooded and sometimes apiculate or retuse at apex; labellum broadly triangular, funnel-shaped, ± 4 cm. long and wide, white, flushed pink at the apex and with a yellow patch in the centre.

Morphology Reproductive morphology Flowers Androecium Stamens

Stamen elliptic, 2-2.5 × 1-1.2 cm.; anthers ± 9 mm. long.

Morphology Reproductive morphology Fruits

Fruit obovoid, ± 12 × 9 mm.

Morphology Reproductive morphology Seeds

Seeds oblong, ± 2 × 1 mm., dark grey, finely striate.

Habitat

Forest, usually near water; 0-1100 m.

Distribution

not known elsewhere K7 P T3 T6 Z

Zingiberaceae, F. N. Hepper. Flora of West Tropical Africa 3:1. 1968

Morphology General Habit

A herb with several leafy stems 3-8 ft. high

Morphology Reproductive morphology Flowers

Flowers in terminal heads, yellow or orange

Ecology

In forest.

Zingiberaceae, J.M. Lock. Flora of Tropical East Africa. 1985

Morphology General Habit

Perennial herb with erect leafy stems 2-5 m. tall.

Morphology Leaves

Leaves elliptic, 20-25 × 4.5-5.5 cm., apex acuminate, narrowed below to the cuneate to subcordate base, glabrous except for a line of ascending marginal hairs; petiole 3-5 mm. long; ligule coriaceous, 5-7 mm. long, glabrous; sheaths striate when dry, glabrous.

Morphology Reproductive morphology Inflorescences

Inflorescences terminal on the leafy shoots, or sometimes (Cribb et al. 11062) terminating separate basal shoots; floral bracts broadly obovate, strongly convex, apiculate, ± 2.5 × 2 cm., each subtending a single flower; bracteoles boat-shaped, keeled, ± 2.5 × 1 cm.

Morphology Reproductive morphology Flowers Calyx

Calyx funnel-shaped, not exceeding the bracts, ± 1.7 cm. long, with 3 obtuse teeth ± 4 mm. long.

Morphology Reproductive morphology Flowers Corolla

Corolla-tube ±1.3 cm. long, hairy inside; petals white, oblong, apiculate, ± 3.5 × 1.5 cm., narrowing slightly towards the base; labellum broadly triangular, funnel-shaped, ± 3.5 × 3 cm., white with a reddish tip and a central yellow mark.

Morphology Reproductive morphology Flowers Androecium Stamens

Stamen narrowly ovate, ± 3 × 1 cm.; anthers ± 9 mm. long.

Morphology Reproductive morphology Fruits

Fruit obovoid, ± 12 mm. long.

Morphology Reproductive morphology Seeds

Seeds oblong, ± 2 mm. long, grey, finely striate.

Habitat

Riverine forest; 300-1070 m.

Distribution

not known elsewhere T3 T4 T6