Amorphophallus prainii Hook.f.

Tuber depressed-globose, 4.0–25 × 2.5–15 cm, root-scars annular, thickened, tuber multiplying by gradual off-setting or division. Leaf solitary, occasionally paired; petiole smooth, rarely slightly rugulose at the base, 10–210 × 0.5–10 cm at base, soft or rather turgid, occasionally the apex becoming an intercalary bulbil, background colour variable, whitish, greenish or reddish brown, mottled with numerous small, blackish green spots and large, circular or oval, creamy white spots, often confluent and internally with small blackish green spots or with a reddish brown centre, sometimes nearly entirely covering the surface, the base often with a bluish purple hue; leaf blade highly dissected, 10–250 cm, rachises winged nearly to the base; main segments several times subdichotomously branched; leaflets elliptic-lanceolate, 5–28 × 1.5–10 cm, long acuminate, base long decurrent. Inflorescence solitary, short pedunculate; cataphylls succulent, broadly lanceolate, 7–37 cm long, usually longer than the entire inflorescence, pink with greyish oblong spots or brown with many small, pale pinkish spots and slightly larger, blackish green to green spots as well as fewer large, pale brown, pale pinkish margined spots; peduncle appearance as petiole but much shorter and sometimes paler, 3–35 × 0.8–6 cm, lengthening markedly in fruit; spathe campanulate, broadly ovate or circular when spread, slightly longer than broad to slightly broader than long, 10–40 × 10–40 cm, base strongly convolute, shallowly constricted at the apex; limb obliquely erect during pistillate anthesis, strongly reflexing just prior to staminate anthesis, or more rarely during or shortly after staminate anthesis, apex obtuse or acute, margin often irregularly undulate, base exterior yellowish green with whitish spots and streaks or with a purplish hue and whitish spots or very pale pinkish white with small, dark green, punctiform spots and large, rounded, whitish spots, margin pinkish, interior dark maroon, limb exterior yellowish green, or bright pale green with whitish spots, the margin without spots and flushed with purple, interior pale yellowish white with bright green stripes along the margin or the latter entirely bright green with some faint whitish spots on the dorsal side, base of spathe within densely clothed with small, shortly ridge-like warts, this part producing a fair amount of fluid during pistillate anthesis and that collects in the spathe base; spadix in small specimens shorter than spathe, otherwise longer, 9–55 cm long, shortly stipitate, stipe ca 1 cm; pistillate flower zone cylindrical or conical, 2–8 × 1–3 cm; ovaries depressed, rarely subglobose, stipitate, circular in cross-section, basal half whitish, upper half pale or dark maroon, 2–3 × 1–2 mm, stipe ca 0.7 mm long; style distinct, 0.5–2 × 0.8–1.2 mm, creamy white, yellowish or maroon; stigma large, capitate, oval in cross-section, obtriangular to cordate in lateral view, distinctly two-lobed, occasionally three-lobed, rarely only shallowly lobed, and then heart-shaped, diam. 1.0 (base)–3.5 (apex), 1.2–3.0 mm high, lobes obtuse, surface minutely scabrate or minutely rugose, pale lemon yellow, bright pale yellow, pale green or creamy white, becoming quite pale at staminate anthesis; staminate flower zone cylindrical or fusiform (small specimens) to strongly obconical (largest specimens), 2–4 × 1.2–3.5 cm, flowers congested; staminate flowers 3–5-androus; creamy white; appendix variable, 1.5–30 × 1–25 cm, rarely subglobose (small specimens), usually broadly ovate-fusiform and laterally compressed with or without a few longitudinal folds, or occasionally with a dense pattern of interconnecting, shallow grooves and raised areas in between, the upper third (or less) often quite abruptly narrowed and tapering to the acute, obtuse, occasionally strongly truncate (in very large specimens) or knoblike apex, the base sometimes stipe-like, the basal half in large specimens clearly inflated, often with staminodes intermediate between stamens and appendix wall and some longitudinal furrows, white, creamy white, or pale sulphur-yellow, sometimes with a pinkish hue. Fruit elongate, 1.7–1.9 cm long, ripening red or orange-red.