Stipes 8-20 cm on sterile fronds, 15-45 cm on fertile fronds, distally tetragonal in cross section; vascular bundle U-shaped; stipes and rachises glabrous; aerophores cushionlike, present only on stipe base. Sterile lamina pinnatifid, 23-65 × 10-20 cm, glaucous abaxially, apex confluent, terminating in a pinnatilobed segment; rachises abaxially trigonous or carinate; pinnae 22-47 pairs; proximal pinnae adnate to rachises, deflexed, abruptly abbreviated; middle pinnae acroscopically adnate to rachises, basiscopically rounded; distal pinnae subequilaterally adnate to rachises, basiscopically rounded; veins usually paired at base. Fertile lamina deeply pinnatifid, 28-60 × 7-14 cm; rachises abaxially carinate; pinnae 20-35 pairs, base broadly adnate to rachises; proximal 1-4 pairs of pinnae much shorter than others, deflexed, often sterile. Paraphyses few, shed early, brown. Spores yellow, with reddish tubercles.
Home