Solitary palm with rough and black stem, 20-25 (-30) m tall. Petiole 60-120 cm, semiterete, edges with hard irregular spines; leaf blade 60-120 cm long, segments 60-80, linear-lanceolate, induplicate. Male inflorescence 90-150 cm long, with c. 7 primary branches, secondary branches c. 30 cm long, c. 2 cm in diameter; sepals narrowly cuneate with truncate inflexed tips; petals shorter, obovate-spathulate; anthers subsessile, large; female inflorescence with flowering portion to 30 cm long, 2.5 cm in diameter, flowers 8-16, spirally arranged, c. 2.5 cm in diameter; sepals fleshy, reniform; petals smaller; ovary subtrigonous; stigmas sessile, recurved. Fruits broadly ovoid, 15-20 cm in diameter, mesocarp fibrous and fleshy. Pyrenes usually 3, obcordate, 6-7 mm broad, black.