56. Athyrium mackinnoniorum (C. Hope) C. Christensen, Index Filic. 143. 1905.
川滇蹄盖蕨 chuan dian ti gai jue
Rhizomes short, erect, apex densely scaly; scales blackish brown in central part, brown in marginal part, narrowly lanceolate. Fronds caespitose; fertile fronds (25-)50-85(-120) cm; stipe blackish brown at base, upward stramineous, (12-) 25-40(-60) cm, (1.5-)2.5-3.5(-7) mm in diam., base similarly densely scaly, upward glabrate; lamina pinnate, narrowly triangular or deltoid-oblong, (13-)35-45(-60) × (15-)24-30(-50) cm, base not narrowed, apex somewhat abruptly narrowed; pinnae pinnatisect to 2-pinnate and pinnules pinnatipartite; pinnae (10-)14-20 pairs, alternate, ascending, shortly stalked (stalk 3-5 mm), in small plants basal pinnae shortened, in larger plants basal pinnae nearly as long as second basal pinnae or slightly longer, subopposite, oblong-lanceolate, (3-)22-30 × (1.5-)5-7 cm at middle, shortly acuminate to caudate-acuminate at apex, abruptly narrowed at base, pinnatisect to pinnate-pinnatipartite; pinnules up to 20-24 pairs, alternate, ascending, oblong-lanceolate, lanceolate, or ovate-oblong, middle pinnules 2.2-3.5(-4) cm × 5-12 mm, base subequilateral, subtruncate, somewhat auriculate on acroscopic side, rounded-cuneate on basiscopic side, slightly adnate to costae, pinnatilobate to pinnatipartite, apex obtuse, acute, or acuminate; pinnule segments up to 8-10 pairs, oblong, 3-6 × ca. 2.5 mm, apex rounded and with few short teeth; upper pinnae similar to basal pinnae and gradually smaller, but slightly narrowed or broadened at base; veins visible on both surfaces, pinnate in segments, lateral veins 2 or 3 pairs, oblique, simple. Lamina papery when dried, pale green, glabrate on both surfaces; rachis and costae stramineous, with sparse pallid short hairs, densely pubescent or glabrate abaxially, with subulate spines on adaxial side at base of costa or costule. Sori shortly linear, J-shaped, sometimes horseshoe-shaped, only 1 per segment, 2-4 on basal acroscopic segments; indusia brown, shortly linear, J-shaped, sometimes horseshoe-shaped, membranous, subentire, persistent. Perispore surface without folds. 2n = 80, 160, 240.
Forests, wet areas, common; 800-3800 m. Chongqing, SE Gansu, Guangxi, Guizhou, NW Hubei, Hunan, Shaanxi, Sichuan, SE Xizang, Yunnan [Afghanistan, N India, Myanmar, Nepal, Pakistan, Thailand, Vietnam].
