31. Diplazium okudairai Makino, Bot. Mag. (Tokyo). 20: 84. 1906.
假耳羽双盖蕨 jia er yu shuang gai jue
Allantodia okudairai (Makino) Ching; Athyrium okudairai (Makino) Ohwi.
Plants evergreen, medium-sized. Rhizome slender, creeping, brown, ca. 3 mm in diam., densely scaly at apex; scales brown, broadly lanceolate, ca. 4 mm, thickly membranous, entire; fronds distant. Fertile fronds up to 90 cm; stipe dark brown at base, upward green-stramineous, 18-35 cm, ca. 2.5 mm in diam., lower part or all parts of stipe with sparse lanceolate brown scales, shallowly grooved adaxially; lamina 1-pinnate, broadly oblong-lanceolate to narrowly ovate, 25-30 × 10-20 cm, apex caudate and acuminate; pinnae up to 12 pairs, subspreading, sickle-shaped lanceolate, 5-15 × 1.5-3 cm, base asymmetrical, cuneate on basiscopic side, deltoid-auriculate on acroscopic side, pinnatilobate, apex caudate and acuminate; lower pinnae with short stalk 2-3 mm, upper pinnae sessile, costa mostly narrowly winged; pinna lobes deltoid, serrate or obtusely toothed; veins visible, pinnate, 4-6 pairs per each lobe, oblique. Lamina herbaceous, green when dry, glabrous on both surfaces; rachis green-stramineous, lower part sparsely scaly; scales brown, narrowly lanceolate, shallowly grooved adaxially. Sori shortly linear, slightly falcate, up to 14 pairs per pinna, single on basal acroscopic veinlet, 2-4 pairs in auricle, inframedial, single or rarely double; indusia light brown, linear, membranous, entire, persistent. Spores bean-shaped, perispore hyaline, often rugate, sometimes rugate projections united to reticulate ornamentation. 2n = 82.
Broad-leaved forests, on wet rocks; 400-2200 m. Chongqing, Guizhou (Anshun, Guiyang), Hunan (Jishou), Jiangxi (Yongxiu), Sichuan, Taiwan (Nantou), Yunnan (Daguan, Suijiang, Zhenxiong) [Japan, Korea].