5. Athyrium ruilicola W. M. Chu, Acta Bot. Yunnan., Suppl. 5: 41. 1992.
瑞丽蹄盖蕨 rui li ti gai jue
Rhizomes creeping, densely clothed with brown, lanceolate scales. Fronds approximate; fertile fronds 23-40 cm; stipe brown at base, upward stramineous, 16-26 cm, 0.5-1.5 mm in diam., base with sparse dark brown lanceolate scales, upward glabrate; lamina 2-pinnate, deltoid-ovate, 8-22 × 3.5-8 cm; free pinnae 3-6 pairs, basal pinnae not shortened or slightly longer, subopposite, shortly stalked, subspreading or slightly ascending, ovate, 1.5-5.5 cm; middle pinnae ovate-oblong, 1.5-4.5 × 1-2 cm, base ± rounded, auriculate at acroscopic side, very shortly stalked, oblique, pinnate, apex acuminate or acute, alternate; pinnules or pinna segments 3-5 pairs, anadromous, deltoid-oblong, 1-10× 2-7 mm, margin shallowly toothed, apex obtuse; free pinnules subequilateral, segments on acroscopic side often auriculate and parallel to costa, basiscopic side broadly cuneate, slightly decurrent and adnate to wing of costa. Veins visible on both surfaces, pinnate in pinnules, lateral veins 3-6 pairs, simple or forked. Lamina thinly herbaceous when dried, yellow-green, glabrate; rachis and costae stramineous, glabrate abaxially. Sori oblong, J-shaped, or horseshoe-shaped across basal acroscopic veins, biseriate along both sides of costule; indusia large, similar to sori, pallid, membranous, ciliate at margin, persistent. Perispore surface with folds.
● 1300-1400 m. Yunnan.
Athyrium ruilicola is similar to A. biserrulatum but differs by the fronds narrower, subdimorphic, stipes of sterile fronds shorter than lamina, stipes of fertile fronds longer than lamina, lateral pinnae 3-5 pairs, and basal pinnae not shortened or slightly longer.