Solitary, robust to massive, pleonanthic dioecious tree palms; stems sometimes ven-tricose, unbranched or branching due to injury. Leaves massive palmate or costapal-mate, often long persisting but finally falling to leave a clean trunk; leaf-sheath short, not clearly distinct from the petiole, splitting longitudinally to produce a central triangular cleft; petiole stout, usually armed with irregularly curved and erose teeth along the margins, terminating in a conspicious adaxial hastula and a much smaller abaxial hastula; lamina divided into numerous induplicate usually bifid segments. Inflorescences axillary, interfoliar, ♂ markedly differing from the ♀. Male inflorescence with an elongate peduncle bearing a prophyll and several bracts; partial inflorescences few-numerous, each borne in the axil of a rachis-bract, the branch-axis adnate to the main axis for some distance above the insertion; branch axis with a basal bare portion terminating in (1–)3 or more rachillae; rachillae massive, cylindrical, bearing connate imbricate bracts, also partly adnate to the axis to form pits, each enclosing a cincinnus of flowers and closed by the free tip of the bract; cincinus bearing 3 or more flowers. Male flowers emerging one by one from the pits; sepals 3, connate into a shallowly or deeply lobed tube; corolla stalk-like at the base, lobes 3, imbricate; stamens 6, with subulate filaments and erect anthers; pistillode minute. Female inflorescence simple or with 1–2 branches, clothed in large imbricate and connate bracts. Female flowers massive, solitary, borne in the axils of these bracts, each subtended by 2 bracteoles; sepals 3, imbricate; petals 3, similar to the sepals; staminodes 6, forming a ring with minute anther rudiments; ovary globose, 3-locular, each locule with a single orthotropous ovule; stigmas 3, very short; septal nectaries conspicuous. Fruit massive, 1–3-seeded, borne within the persistent perianth-segments; epicarp usually smooth or cracked vertically; mesocarp fibrous and pulpy. Seeds each enclosed in a separate endocarp; endosperm homogeneous with a central hollow; embryo apical. Germination remote tubular; eophyll simple.