13. Diplazium donianum (Mettenius) Tardieu, Asplén. Tonkin. 58. 1932.
双盖蕨 shuang gai jue
Rhizome long creeping or creeping to oblique, 3-4(-8) mm in diam., with black, dense, fleshy, robust roots, apex densely scaly; scales brown to dark brown, lanceolate, thick, margin toothed; fronds caespitose or approximate. Fertile fronds up to ca. 80 cm; stipe brown-black at base, upward stramineous or brown-yellow-stramineous, 25-50 cm, 2-3 mm in diam., base densely scaly, upward gradually glabrous, grooved abaxially; rachis gray-brown-stramineous, glabrous; lamina 1-imparipinnate, elliptic or ovate-elliptic, 25-40 × 15-25 cm; lateral pinnae usually 2-5 pairs, all equal in size, subopposite or upper pinnae alternate, oblique, basal pinnae with short stalk 2-4 mm, upper pinnae sessile, ovate-lanceolate or elliptic, 10-20 × 3-5 cm, long acuminate at apex, often spreading or slightly subfalcate, base rounded-cuneate or subrounded, margin entire, repand, or lobed, apex serrate or crenate, incurved when dry; costae raised, rounded abaxially, shallowly grooved on adaxial side; veinlets 3-5 per group, straight. Lamina leathery or thickly papery, gray-green or brown-green when dry. Sori and indusia long linear, oblique or slightly oblique, often from midrib to laminar margin, on all veinlets, single or double. Spores semicircular in equatorial view, perispore hyaline, wide, with few rugate, not prominent granular projections.
Evergreen broad-leaved forests, beside streamlets; 100-1600 m. Anhui, Fujian, Guangdong, Guangxi, Guizhou, Hainan, Taiwan, Yunnan [Bhutan, N India, Japan, Myanmar, Nepal, Vietnam].