Stems to 8 m tall. Leaves 100-120 cm long, moderately keeled, with 200-230 pinnae, mid-green, semi-glossy. Petiole 24-26 cm long, unarmed or spinescent for 5-50% of length. Median pinnae 11-22 cm long, 5-7.5 mm wide, narrowed to 3-4 mm at base (to 50-60% of maximum width), inserted at 50-70° to rachis, 8-9 mm apart, glabrous; margins slightly recurved; midrib flat above, raised below. Cataphylls linear, soft, 5-9 cm long, densely orange-woolly or-floccose. Pollen cones not seen. Microsporophyll lamina c. 40 mm long, c. 15 mm wide; apical spine c. 4 mm long. Megasporophylls 23-28 cm long, with 4-6 ovules; lamina lanceolate, 50-55 mm long, 15-30 mm wide, regularly dentate with 22-24 lateral spines 1-4 mm long and 1-2 mm wide; apical spine 21-25 mm long. Seeds 30-35 mm long, 27-29 mm wide.
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