Anchomanes difformis (Blume) Engl.

Araceae, S.J. Mayo. Flora of Tropical East Africa. 1985

Morphology General Habit

Tuber massively thickened, 6–20 cm. broad or more, growing horizontally, with distinctive annular leaf-base scars and growing point situated obliquely.

Morphology Leaves Cataphylls

Cataphylls 20–30 cm. long, 3–4 cm. broad, oblong, membranous, speckled, acute to subacute.

Morphology Leaves

Petiole aculeate, up to 3 m. long, 1–4 cm. thick, dark to purplish green with whitish speckling; prickles whitish-green, 2–3 mm. long; blade up to 1.5 m. broad, ultimate lobes up to 20 cm. long, 10–13 cm. broad, dark green.

Morphology Reproductive morphology Inflorescences Peduncles

Peduncle 50–180 cm. long, 0.7–1 cm. or more thick, aculeate, with coloration similar to petiole.

Morphology Reproductive morphology Inflorescences Bracts Spathe

Spathe oblong-ovate, green, greenish to purplish brown or brick red, 14–30 cm. long, 3–5 cm. in diameter, acuminate.

Morphology Reproductive morphology Inflorescences Spadix

Spadix subcylindric, 10–20 cm. long, shorter than spathe, staminate part 7–12 cm. long, 1–1.5 cm. in diameter, narrowing slightly towards blunt apex, pistillate part 3–8 cm. long, 1.5–2 cm. in diameter.

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens subsessile, 2–2.5 mm. long, 1.5 mm. broad, cream-coloured to white.

Morphology Reproductive morphology Flowers Gynoecium Pistil

Pistil 4 mm. long; ovary 2.5–3 mm. in diameter, glossy purple to pink; style up to 2 mm. long, sometimes very short, narrowing apically and ± sharply deflexed; stigma bilabiate, zygomorphic and V-shaped when viewed face-on, about 1 mm. in diameter, facing towards spadix-base, cream to purplish.

Morphology Reproductive morphology Fruits

Berries oblong-ellipsoid, red to purplish, 1.5–2 cm. long, 0.8–1 cm. in diameter, rounded, umbonulate, 1-seeded.

Morphology Reproductive morphology Seeds

Seed obovoid, 1.5 cm. long, 0.8 cm. in diameter, with prominent oblong raphe.

Habitat

Riverine forest, rain-forest; 700–1200 m. (and possibly lower)

Distribution

T4 U1 U2 also West Africa from Sierra Leone to Cameroun

CATE Araceae, 17 Dec 2011. araceae.e-monocot.org

Diagnostic

Spathe 5-9 in. long.

General Description

Plant erect on an enormous horizontal tuber, often reaching 50 - 80 cm long, and 10 - 20 cm in diameter, part of which emerges from the ground and is indented, each zone representing growth activity for one season. LEAVES: Petioles 0.8 - 2 (-3) m high, emerging from the tuber, spiny, greyish green to pale green, or purplish mauve, mottled with very pale spots; Blade very large, divided at the apex of the petiole into 3 identical divisions, each division carrying the leaflets; those at the extreme ends, 8 - 32 x 4 - 12 cm, trapeziform, often torn into two further leaflets, which are symmetrical and equally trapeziform, at the base they are more or less decurrent on the rachis; basal leaflets 5 - 18 (-30) x 3 - 10 (-16) cm, rhomboidal to ovate, sessile and not decurrent on the rachis, the two types of leaflets are generally acuminate. INFLORESCENCE: Peduncle enveloped in a whitish violet bract, emerging also from the tuber, generally appearing after the leaf is over, green to purplish green, scattered with whitish spots, less long and spiny than the petiole; spathe 9 - 22 (-30) cm yellow, green or purple externally, often mottled with red or cream spots, generally pale green internally, slightly convolute at base, the rest boat-shaped, the apex acuminate or acute; spadix sessile, cylindric (4-) 8 - 18 (-22) x 0.6 - 1.5 cm, a lot shorter than the spathe; female flowers ca. 1/6 to 1/3 longer than the male flowers, which are cream to white; stamens prismatic, 4 sided, opening by pores; female flowers orangish, green with cream markings, or purple with pink or white markings; ovary conical surmounted or not by a style short or long, generally curved towards the base of the spadix; stigma reniform; 1-locular, ovule 1, anatropous. INFRUCTESCENCE: Berries ovoid, 18 - 10 mm, becoming green then yellow, eventually violet with purple spots or brown at the apex, or white with violet or purple apices. Apex of peduncle curving towards the sun.

J. R. Timberlake, E. S. Martins (2012). Flora Zambesiaca, Vol 12 (part 1) Araceae. Royal Botanic Gardens, Kew

Morphology General Habit

Perennial herb

Vegetative Multiplication Tubers

Tuber massively thickened, 6–20 cm in diameter, growing horizontally, with distinctive annular leaf-base scars, growing point situated obliquely, partly emerging from ground

Morphology Leaves Cataphylls

Cataphylls oblong, subtending petiole

Morphology Leaves Petiole

Petiole up to 300 × 1–4 cm, dark to purplish green with whitish speckling, with 2–3 mm long, outward-pointing, whitish-green prickles; blade up to 150 cm wide, dark green

Morphology Reproductive morphology Inflorescences Peduncles

Peduncle 50–180 × 0.6–1 cm, markings similar to petiole, smooth to prickly

Morphology Reproductive morphology Inflorescences Bracts Spathe

Spathe oblong-ovate, 14–30 × 3–5 cm, acuminate

Morphology Reproductive morphology Inflorescences Spadix

Spadix subcylindric, 12–30 cm long, shorter than spathe; male zone 5.5–12.5 × 0.7–1 cm, tapering towards blunt apex; female zone 1.5–3.5 × 0.8–1.5 cm

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens prismatic, 1.5–2.5 × 1.5 mm, creamy-white

Morphology Reproductive morphology Flowers

Female flowers c.4 mm long; ovary 1.5–2.5 mm wide; style up to 2 mm long, sometimes ± sessile, narrowing apically, downward pointing; stigma reniform to discoid

Morphology Reproductive morphology Fruits

Berries oblong-ellipsoid, red to purplish or white, 0.9–2 × 0.5–1 cm, rounded, 1-seeded

Morphology Reproductive morphology Seeds

Seed obovoid, 0.7–1.5 × 0.4–0.8 cm.

Distribution

Zambia. Also in W Africa from Congo to Benin, Burkina Faso, Gambia, Ghana, Guinea- Bissau, Guinea, Ivory Coast, Liberia, Nigeria, Senegal, Sierra Leone, Togo, Central African Republic, Cameroon, Equatorial Guinea, Gabon, Gulf of Guinea Is., Zaire, Chad, Sudan, Uganda, Tanzania and Angola.

Ecology

In riverine and swamp forest, Brachystegia and chipya woodland, sometimes on termite mounds; 900–1400 m.

Conservation

Restricted distribution in the Flora area, but widespread elsewhere; not threatened.

Recognition

Flowers are needed to separate these two Anchomanes species but are not always present in herbarium specimens. A. difformis is predominantly a western species and only enters the Flora area in Zambia, whereas A. abbreviatus appears to be confined to Eastern Africa. A. welwitschii is sometimes considered to be a separate taxon with a sessile discoid stigma and paler colouration. However intermediate forms exist, making separation unreliable. More research on living plants is required.

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

Morphology General Habit

Savanna herb similar to A. difformis but the leaf generally smaller, about 4 ft. high

Morphology Reproductive morphology Inflorescences

Spathes yellow-green, ovaries green and stigma orange.