Massive, solitary, unarmed, pleonanthic, dioecious, tree palms. Stem erect, partly obscured by marcescent leaf sheaths above, becoming bare basally, cortex hard, pith soft. Leaves large, reduplicate, briefly costapalmate; sheath tubular at first, splitting opposite the petiole, the margins sometimes bearing coarse fibres; petiole conspicuous, adaxially channelled near the base, otherwise circular in cross-section, smooth, unarmed; blade bearing a low crest adaxially at the base, abaxially with a low ridge; blade orbicular, divided along abaxial folds almost to the insertion into numerous crowded single-fold segments, very shortly bifid at their tips, midribs prominent, transverse veinlets not conspicuous. Inflorescences solitary, interfoliar, the staminate and pistillate superficially similar; prophyll short, tubular, 2-keeled, with 2 short triangular lobes, striate; peduncle shorter than the rachis, elliptical in cross-section, bearing numerous overlapping distichous, tubular, striate, peduncular bracts, each with a short, triangular, dorsal limb and a shallow point on opposite side; rachis bracts numerous, completely sheathing the branches, distichous, as the peduncular, each subtending a ± pendulous or spreading first-order branch; the first-order branch bearing a short, 2-keeled, striate, tubular prophyll, and 1–few empty distichous bracts, subsequent bracts tubular, flaring, short, each subtending a very short or moderate, straight or recurved rachilla; staminate rachilla catkin-like, bearing a basal, tubular, 2-keeled prophyll and crowded, spirally inserted bracts, each subtending a pair of staminate flowers, each flower bearing a basal 2-keeled bracteole; pistillate rachilla very short, not catkin-like, bearing a basal, tubular, 2-keeled prophyll, and subdistichous, ± explanate bracts, each subtending a solitary pistillate flower with a flattened, 2-keeled bracteole, and often also bearing a minute spathulate, second bracteole, with 2 minute flanges on its abaxial surface. Staminate flowers with calyx tubular, shortly 3-lobed, often densely scaly; petals 3, elongate, much exceeding the calyx, valvate, coriaceous, joined briefly at the base; stamens 6, the filaments ± free, thick, ± angled, elongate, anthers elongate, basifixed, latrorse; pistillode minute. Pollen spheroidal, symmetric; aperture either a large distal pore or a short sulcus; ectexine intectate, very finely clavate, interspersed with bottle-shaped spines set in, and loosely connected to, cavities in a wide foot layer bulging strongly inwards beneath each spine, the inner face of the foot layer finely lamellate, aperture margins similar; longest axis 54–65 µm [1/2]. Pistillate flowers larger than the staminate; calyx tubular, striate, shortly 3-lobed, often densely scaly; corolla tubular in the basal 1/3 – 1/2, with 3 valvate, elongate lobes distally; staminodes 6, connate laterally by their flattened broad filaments and adnate to the corolla at the mouth of the tube; gynoecium trilocular, triovulate, ± rounded, covered in vertical rows of reflexed scales, style short, conical, stigmas 3, ovules anatropous, basally attached. Fruit ± rounded, very large, usually 1-seeded, with apical stigmatic remains; epicarp covered in many neat vertical rows of reddish-brown, reflexed scales, mesocarp rather thick, fleshy, endocarp not differentiated. Seed rounded, attached near the base, apically with a blunt beak, testa thin, endosperm homogeneous; embryo basal. Germination adjacent-ligular; eophyll with a pair of divergent leaflets (?always). Cytology: 2n = 30.