2. Amorphophallus Blume ex Decne., Nouv. Ann. Mus. Hist. Nat. 3: 366 (1834).
By: Himanchal T. Magar & Mohan Siwakoti
Taxon Description
Perennial herbs. Tubers corm-like. Flowering before leafing. Leaf single, compound, 3-partite, segments commonly once to several times pinnately divided into leaflets; secondary veins of leaflets diverging obliquely from midrib, connected by inter-marginal veins; leaf sometimes bulbiferous. Monoecious. Inflorescences borne on stout peduncle subtended by membranous cataphylls; cylindric, dense flowers, male and female contiguous, neuter 0. Spathe various, limb campanulate infundibular convolute or open, marcescent. Spadix exerted or included and sessile to shortly stipitate. Spadix appendix large, short or long. Anthers 2–4, sessile, cells oblong, pores apical. Ovary globose or obovoid, 1–4-celled, ovules solitary, sub-basal, anatropous; style short or long, stigma entire or 2–4 lobed. Berries subglobose or obovoid. Seeds albuminous; embryo macropodous.
Taxon Statistics
About 200 species: paleotropical, W to E Africa, S and SE to E Asia, N Australia, Pacific islands. Two species in Nepal.
Key to Species
1a Bulbils borne at primary and sometimes secondary divisions of leaf and leaflets ……..………….. 1. A. bulbifer
b Bulbils absent ……………………………………………………….………….…..…………………….…………..………… 2. A. napalensis
1. Amorphophallus bulbifer (Roxb.) Blume, Rumphia1:148 (1837).
Arum bulbiferum Roxb., Fl. Ind. ed. 3: 510 (1832); Conophallus bulbifer (Schott) Schott; Pythonium bulbiferum Schott.
Tuberous herbs, 50–120 cm. Tubers sub-globose, ca. 4.5 cm diam.; bulbils borne at primary and sometimes secondary divisions of leaf and leaflets. Leaves divided into 3 segments, segments shortly petiolate, almost immediately branched into large pinnatisect sections, petioles dark greyish-green, mottled pale green, 0.3–1 m, smooth; leaf blade narrowly oblong, 6.5–19.5 X 3–7.5 cm, margin entire, base cuneate, apex finely acuminate. Peduncles mottled, stout, shorter than petiole, 13–20 cm. Spathe mottled greenish outside, pink to crimson inside, margins strongly overlapping at base, 12–14 cm; limb broadly ovate, apex subacute. Spadix almost equaling spathe, female zone 1.5–3 X ca. 1.3 cm, neuter zone absent, male zone 4–5 X 1.7–2 cm; appendix white or pink, swollen, subacute, 6.5–8 X ca. 2.5 cm.
Distribution: Nepal, E Himalaya, Assam-Burma and S Asia.
Altitudinal range: 300–900 m.
Ecology: Moist on Shorea robusta forest, neglected areas and on lime stone scree.
Flowering: May–June. Fruiting: May–June.
2. Amorphophallus napalensis (Wall.) Bogner & Mayo, Aroideana 8(1): 19 (1985).
Thomsonia napalensis Wall., Pl. Asiat. Rar. 1(4):83. t.99 (1830).
Tuberous herbs, 60–130 cm. Tubers sub-globose, 2.5–6 cm diam.; bulbils absent. Leaves divided into 3 segments, segments more elongate, divided into numerous leaflets, petioles dark greyish-green, mottled pale green, ca. 35–50 cm, smooth; leaf blade narrowly oblong, 5.5–12 X 1.2–2.5 cm, margin entire, base cuneate, apex abrubptly and finely acuminate. Peduncles mottled, stout, as long as or longer than petiole, (–10)35–100 cm. Spathe not mottled outside, convoluted below, 13–26 X 7–11 cm; limb oblong to oblong-ovate or ovate-lanceolate, apex subacute. Spadix shorter than spathe, female zone 2.5–3 cm, neuter zone absent, male zone 5–24 cm; appendix yellow, tuberculate, 7.5–10 cm.
Distribution: Nepal, E Himalaya, Assam-Burma and S Asia.
Altitudinal range: 700–1500 m.
Ecology: Shady place of tropical forest, open place, on the edge in open grassland.
Flowering: April–July. Fruiting: April–July.