Trunk to 30 m tall, to 30 cm diam. Leaves 9–12, to 4.5 m long, becoming vertically orientated; leaf sheath dark green to green-purple. Pinnae 70–90 each side of rachis, to 100 cm long, dark green on both surfaces; ramenta present. Inflorescence to 150 cm long, branched to 4 orders; axes white to yellow green, becoming mauve in infructescence; rachillae to 55 cm long, pendulous, moderately flexuose distally. Flowers closely spaced on rachilla; floral bracts raised with sharp margins; perianth lilac to purple. Staminate flower to 6 mm long; stamens 9–18; filaments deflexed; pistillode about equal to petals. Pistillate flower to 5 mm high. Fruit ovoid, 10–15 mm long, 6–11 mm wide; stigmatic remains apical; mesocarp fibres to 1 mm wide, flat, sparingly branched, remaining compact in the dried state. Seed globose, to 9 mm diam.; raphe fibres embedded, strongly adherent.