滇西蹄盖蕨 dian xi ti gai jue

Rhizomes short, erect or ascending. Fertile fronds up to 1.5 m; stipe chestnut-black at base, upward stramineous, 50-60 cm, ca. 4 cm in diam., base densely clothed with brown, lanceolate large scales, upward glabrate; lamina 2-pinnate-pinnatifid, oblong, up to 85 × 40-45 cm, base narrowed, apex long acuminate; pinnae ca. 25 pairs, lower pinnae subopposite, upper pinnae alternate, ascending, subsessile; basal 2 or 3 pairs of pinnae slightly shortened, basal pinnae ca. 9 × 2.5 cm; middle pinnae lanceolate, 23-28 × 5-6 cm at middle, base equilateral, truncate, pinnate-pinnatifid, apex long acuminate; pinnules 22-26 pairs, alternate, spreading, oblong-lanceolate, 2.5-3 cm × 8-10 mm at base, base subequilateral, ± decurrent and connate to each other by wing of costa, pinnatifid to 1/2, apex acute; pinnule segments 8 or 9 pairs, oblong, dentate at apex; veins visible adaxially, clearly visible abaxially, pinnate in segments, lateral veins 2 or 3 pairs, oblique, simple. Lamina firmly herbaceous when dried, greenish brown adaxially, yellow-green abaxially, glabrate on both surfaces; rachis and costae abaxially stramineous, with sparse short hairs. Sori suborbicular or elliptic, inframedial on basal acroscopic veins, single per segment, often 2 or 3 in basal acroscopic larger segments, biseriate on both sides of costule, 6-10 pairs per pinnule; indusia pale brown, somewhat J-shaped or horseshoe-shaped, sometimes shortly linear, membranous, erose at margin, occasionally ciliate, persistent. Perispore surface without folds.

● In shrubs, streamsides, damp areas; ca. 3200 m. Yunnan.