Usually scandent, strongly prickly, occasionally erect tufted dioecious palms, solitary or in small clumps, usually with very long stem. Leaves pinnate, 1-(9), divided into often numerous segments, rachis often spinous, with sharp hooked spines, leaf sheath usually very prickly, sometimes produced into ligula or ochrea. Inflorescence axillary, much branched, armed, often with a sterile whip-like prolongation. Bracts many, tubular, persistent. Flowers minute, usually in 2 ranks, often scorpioid, male flowers small, solitary; calyx 3-toothed, cup-shaped, coriaceous; petals 3, coriaceous, valvate; stamens 6, filaments small, anthers dorsifixed, female flowers with a sterile male flower in the same bracteole; calyx 3-toothed, cup-shaped; corolla 3-fid, tubular below, valvate, staminodes forming a cup. Ovary 3-chambered, covered with retrorse scales; stigmas 3. Fruit globose or ellipsoid, covered with scales and persisting stigmas on the top. Seeds usually solitary, rarely 2-3, covered by sarcotesta. Endosperm homogeneous and horny or ruminate.