Protologue: in A. & C. DC., Monogr. phan. 2 (1879): 316
Synonym: Conophallus spectabilis Miq.
Tuber to 20 cm in diam. Leaf solitary. Petiole nearly smooth, dark green with grey and brown spots, 100-150 cm long. Lamina 100-150 cm in diam., rachises distally narrowly winged, proximally unwinged. Leaflets narrowly elongate elliptic to elongate elliptic, 13-30 cm long, 3-12 cm in diam., long acuminate, base narrowly decurrent, acumen 2.5-4 cm long. Inflorescence solitary, long peduncled. Peduncle as petiole, 120-220 cm long. Spathe erect, elongate-ovate, 34-60 cm long, 15-25 cm in diam., top acute, bending forward and hanging over the appendix, outside base ground colour olive green, nearly entirely covered by confluent, rounded, bright pale green spots with a paler margin, sometimes accompanied by larger whitish areas, upwards turning purple, inside base dark purple, above that a pale whitish greenish zone and the rest dark purple, limb outside glossy blackish purple with some strong ridges, inside glossy dark maroon, margin undulate, base within with scattered warts, these shallow and isolated or narrow ridge-like. Spadix sessile, much shorter than the spathe, 25-40 cm long. Female zone cylindric, 2.5-8 cm long, 1-2 cm in diam.; flowers congested or more or less distant. Male zone obconic or elongate obconic, 2-9 cm long, 1.5-4 cm in diam. at the top; flowers congested or in low-angled, not very distant spirals, near the appendix-base with a few, elongate conical staminodes. Appendix elongate fusiform-conic, 10-23 cm long, 2.5-6 cm in diam.; obtuse, subacute or acute, pale brownish purple or yellowish brown, densely verruculose, verrucae shortly elongate, especially distinct at the base. Ovaries slightly depressed-globose, 2.5-4 mm in diam., 1.5-2 mm high, circular or + quadrangular in cross-section, all green or upper part purple, one locule, one basal ovule. Style very short, 0.3-0.5 cm long, c. 1 mm in diam., purple. Stigma conical, asymmetric with one peripheral large conical lobe with a deep, semi-circular groove at the base, 1.5-2 mm in diam., 1-2 mm high, dark purple stylar tissue protruding just beyond the top of the lobe and at several places along the margin. Male flowers consisting of 3-5 stamens. Stamens 2.5-3 mm long, 1-2 mm in diam., ± rectangular or haltere-shaped in cross-section. Filaments 0.8-1 mm long but in the lowermost flowers longer (c. 1.3 mm), basally connate to entirely connate. Anthers ± truncate, 1.5-2 mm long but in the lowermost flowers much shorter (c. 0.7 mm), glossy dark purple, connectives broad, sometimes elevated, pores shortly elongate, apical or sublateral. Berries suboblong, orange-red, 1-seeded.
Distribution: Endemic to West Java.
Habitat: In margin of montane forests, at 1200-1800 m altitude.
Amorphophallus spectabilis is easily distinguished from other long-pedunculate species on Java by the spadix being much shorter than the spathe and the lack of disc-like broadenings of the appendix base or in the male zone and by the very short style.
It is apparently a rare species. Several recent field trips throughout the island of Java have failed to find the species.