Youngest stage with simply pinnate fronds to 9 cm long with deeply crenate articulate pinnae 8 by 4-5 mm, apex of frond a narrow lobed lamina not articulate; next stage with basal pinnae pinnate and in some cases deflexed across rhizome, upper simple pinnae to 22 by 11 mm, pinnules of basal pinnae to 6 by 4 mm; later fully bipinnate fronds 2-ranked on slender rhizome are like acrophylls but smaller. Adult rhizome 7-8 mm or more wide, smooth. Sterile acrophylls with stipes 10-20 cm, lamina to 60 cm long, bipinnate; pinnae 15-24 cm long, articulate to rachis, pinnate with to 20 or more pairs of articulate pinnules which grade into the small widely-spaced lobes of a narrow apical lamina; pinna-rachis winged throughout; pinnules sessile or nearly so, base very asymmetric, narrowly cuneate basiscopically, very broadly cuneate and usually with a well-developed auricle acroscopically, edges crenate, apex rounded, largest pinnules 15-25 mm long, 6-8 mm wide above auricle; brown bullate scales on lower surface of costa. Fertile fronds somewhat smaller than sterile; pinnules distinctly stalked, 7-15 mm long, c. 2 mm wide when dry, distinctly auricled.
Home