Very tall dioecious fan leaved plams. Leaves massive, yellowish with broad split base; lamina 90-120 cm across; leaflets induplicate, a thread hanging form each sinus. Petiole armed with irregular spines; a hastula on both surfaces. Inflorescence very long, sheathed with several bracts which are tubular at base; male inflorescence not much branched; male flowers very small, in depressions within imbricating bracts; sepals 3, wedge-shaped, imbricate; petals 3, smaller then sepals, imbricate, obovate-spathulate. Stamens 6, filaments connate with corolla; anthers large, oblong. Female inflorescence less branched than the male; female flowers much large, solitary globose; perianth fleshy; sepals 3, imbricte; petals 3, small convolute; staminodes 6-9; ovary globose, 3-4-celled; ovule orthotropous. Fruit 15-20 cm in diameter; wall fibrous, containing 3 seeds, each with a hard stony wall; endosperm homogeneous.