Cyrtosperma merkusii (Hassk.) Schott

Robust to gigantic herbs to 4 m tall; rhizome short and slender to very large, sometimes globose and weighing up to 70 kg, weakly to freely suckering. Leaves several, sagittate, rarely hastate; petioles c. 40 cm to c. 3 m long, heavily armed -often very heavily with stout conical spines towards the base - to unarmed (cult.); blade c. 30 cm to 1.3 m long, to c. 80 cm wide, armed or not abaxially, held more or less horizontally to vertically with the posterior lobes down; posterior lobes somewhat exceeding the anterior ones; primary venation of the anterior lobe curvinerved (in small specimens) to pinnate (in large ones); posterior midribs naked in the sinus for c. 5 cm. Inflorescence solitary on a peduncle similar to but usually shorter than the petioles and like them with a geniculus at the top turning blackish on drying. Spathe very variable in size, colour, and shape, 2.5 to c. 30 cm long, white to yellow to green to purple, if pale then usually with purplish streaks outside, rolled back to deflexed to erect (with increasing size), in the latter somewhat constricted above the level of the apex of the spadix; spadix 2-24 cm long, equalling or exceeding half the length of the spathe, sessile to stipitate, if stipitate than stipe free or adnate to the spathe. Flowers hexamerous; ovary (l-)2-ovulate; stamens exserted from the tepals at male anthesis. Fruit reddish orange, sessile, 1 (-2)-seeded. Seed campylotropous, almost circular in profile to shallowly kidney-shaped, 5-11 mm long; seed-coat brown with c. 3 raised, warty, longitudinal crests to sparsely and more or less irregularly warty and faintly crested.