Amorphophallus Blume ex Decne.

Herbs, terrestrial, small to massive. Stem subterranean, tuberous, rarely a chain of tubers or a true rhizome; rhizome ± creeping. Leaves usually solitary, rarely paired or more; petiole terete, rarely angulate, shallowly grooved, or partly rugulose, rarely entirely verrucate or hairy; leaf blade decompound, divided into 3 main segments; main segments equally long or anterior shorter than posterior ones (blade ± subpedate); rachises naked, narrowly or broadly winged and often carrying supernumerary leaflets on proximal parts; bulbils sometimes developing on leaves, either epiphyllar, intercalary (developing inside rachis), or half-epiphyllar (base developing in rachis, apex exposed beyond rachis). Inflorescence 1, rarely 2 or 3 (synflorescence) or more per season (then developing from different buds on stem), epigeal, rarely partly buried, solitary or simultaneous with or directly preceding leaf development, rarely emerging after leaf development. Spathe base convolute, rarely open or connate, not or clearly separated from limb by a constriction, outside variously colored, variously shaped, often cymbiform or campanulate, rarely funnel-shaped; limb erect, spreading, oblique, or arching. Spadix sessile or shortly stipitate; female zone contiguous with male zone or separated from it by a sterile zone; flowers sometimes surrounded by staminodes; female flowers consisting of 1 pistil; ovary sessile or shortly stipitate, 1-4-loculed, with 1 ovule per locule, basifixed, or rarely axillary ca. halfway up ovary; style present or (nearly) absent, clearly separated from ovary or less so, sometimes with apical projections ("branches") extending beyond stigma; sterile zone (when present) covered with staminodes, rarely partly or entirely naked; male zone cylindric, fusiform, conic, or obconic; male flowers consisting of (1-)3-6(-8) stamens; stamens depressed or elongate; filaments present or nearly absent, separated or partly or entirely fused within a flower or rarely fused between adjacent flowers; anthers bithecal; thecae 2-celled (with 2 pollen sacs), rarely 1-celled; pores apical, rarely lateral or subterminal; pollen inaperturate, globose or elliptic, exine rarely absent, psilate, striate, verrucate, echinate, areolate, porate, fossulate, reticulate, or scabrous; appendix rarely absent, contiguous with male zone or separated by a constriction or a short stipe, sometimes with large longitudinal folds or ± irregular deep cracks. Berries crowded or distant, ripening red, rarely blue, globose, ovoid, or narrowly elliptic, smooth or rarely verrucate, 1-4-seeded. Seeds usually with a distinct raphe; endosperm absent.