Moderate, solitary, spiny when young, sparsely armed or ± unarmed at maturity, pleonanthic, monoecious palm. Stem erect, becoming bare, conspicuously ringed with leaf scars, the juvenile bearing abundant black spines, usually ± unarmed at maturity. Leaves large, bifid, lobed and pinnately ribbed but not pinnatifid, neatly abscising; sheaths becoming open, not forming a well-defined crownshaft, covered in abundant tomentum, easily detached spicules, and scattered, large black spines when young, becoming markedly less spiny as maturity is reached, sheath margin irregularly ligule-like, tattering; petiole well developed, adaxially channelled, abaxially rounded, sparsely scaly, in juveniles bearing abundant, large, black spines abaxially; rachis bearing black spines in the proximal region in juveniles; blade bifid, with very conspicuous, pinnate ribs, splitting along abaxial ribs to 1/8 to 1/3 the rib length into briefly bifid lobes, sometimes split further by wind, blade bright green, often reddish-tinged, adaxially glabrous, abaxially with abundant dot-like scales and large ramenta along the adaxial folds near the rachis, transverse veinlets obscure. Inflorescences solitary, interfoliar, branching to 1–2 orders proximally, to 1 order distally, protandrous; peduncle elongate, winged at the base, oval in cross-section, unarmed, glabrous; prophyll inserted some distance from the base of the peduncle, persistent, very coriaceous, tubular, 2-keeled, the keels tending to be irregularly split or toothed, splitting apically for a short distance, scaly or sparsely tomentose, unarmed or armed with sparse to abundant, short, black spines; peduncular bract 1, inserted some distance above the prophyll but included within it, ± woody, conspicuously beaked, deciduous, unarmed, minutely scaly, tubular at first then splitting along ± its entire length; rachis much shorter than the peduncle; rachis bracts minute, triangular, inconspicuous; first-order branches spirally arranged, crowded, ± pendulous, their bases somewhat swollen; rachillae glabrous, slender, elongate, flexuous, with a very short, bare area at the base, above this bearing spirally arranged, superficial triads, except near the tip where bearing solitary or paired staminate flowers; bracteoles minute, rounded. Staminate flowers slightly asymmetrical; sepals 3, distinct, imbricate, low, ± rounded, keeled; petals about 4–5 times as long as the sepals, 3, distinct, valvate; stamens 15–18, filaments short in bud, at anthesis becoming elongate, slender, anthers elongate, medifixed, basally sagittate, latrorse; pistillode absent. Pollen ellipsoidal bi-symmetric; aperture a distal sulcus; ectexine tectate, coarsely perforate with broad-based supratectal spines, often basally branched, aperture margin similar; infratectum columellate; longest axis 23–30 µm [1/1]. Pistillate flowers ± globular, about the same size as the staminate; sepals 3, distinct, imbricate, rounded, ± keeled; petals 3, distinct, rounded, imbricate, with short, triangular, valvate tips; staminodes 6, tooth-like; gynoecium asymmetrically ovoid, unilocular, uniovulate, stigmas 3, apical, very low, ovule laterally attached, ?campylotropous. Fruit 1-seeded, relatively small, ovoid to ellipsoidal, red, with persistent perianth whorls, and subbasal stigmatic remains; epicarp shiny, mesocarp thinly fleshy with a thick layer of tannin cells external to the endocarp, endocarp thin, cartilaginous, with basal round operculum. Seed ovoid, basally attached, with rounded hilum and sparse, anastomosing raphe branches, endosperm deeply ruminate; embryo basal. Germination adjacent-ligular; eophyll lanceolate, entire. Cytology: 2n = 32.