乌蒙山蹄盖蕨 wu meng shan ti gai jue

Rhizomes slender, long creeping, clothed with brown, narrowly lanceolate scales at apex and stipe bases. Fronds approximate; fertile fronds up to 60 cm; stipe brown at base, upward stramineous, ca. 17 cm, ca. 2 mm in diam. at base, upward glabrate; lamina 3-pinnate, ovate-oblong, ca. 40 ×16 cm at middle, base hardly narrowed, apex acuminate; pinnae ca. 14 pairs, opposite, ascending, shortly stalked (stalk ca. 2.5 mm), basal pinnae hardly shortened; second basal pair of pinnae oblong-lanceolate, up to 13 × ca. 5 cm, base subtruncate, 2-pinnate, apex acuminate; pinnules ca. 12 pairs, alternate, subspreading, sessile, oblong-lanceolate, up to 2.5 × ca. 1 cm, base rounded-cuneate, slightly decurrent and ± adnate to wing of costa, pinnatipartite, almost cut to costules, apex acuminate; secondary pinnules 5 or 6 pairs, ascending, oblong-lanceolate, basal secondary pinnules up to 7 × ca. 3 mm, upper pinnules gradually shortened, margin toothed, apex acute and with 3 or 4 long spinelike teeth. Veins thick, slightly impressed adaxially, protuberant abaxially, pinnate in secondary pinnule, lateral veins 4 pairs, oblique, simple. Lamina herbaceous when dried, pale green, with sparse pale hairs adaxially, abaxial side of costae and costules with sparse short hairs. Sori large, oblong, 2-6 sori per secondary pinnule; indusia pale brown, large, oblong or J-shaped, membranous, margin unequally toothed, persistent. Perispore surface prominently with folds.

● About 1800 m. N Yunnan (Luquan, Wumeng Shan).

Athyrium wumonshanicum is similar to A. biserrulatum in the frond shape. However, its lamina is 3-pinnate, with short hairs on the adaxial side, and with aristate teeth on the margin.