甘肃双盖蕨 gan su shuang gai jue

Basionym: Allantodia kansuensis Ching & Y. P. Hsu, Fl. Tsinling. 2: 219. 1974.

Plants evergreen, medium-sized. Rhizome ascending, ca. 1.5 cm in diam., apex like base of stipe, sparsely scaly; scales brown, broadly lanceolate, ca. 5 mm, margin sparsely toothed; fronds caespitose. Fertile fronds 60-80 cm; stipe black at base, upward stramineous, 30-40 cm, 2-3 mm in diam.; lamina 2-pinnate with pinnules pinnatifid, deltoid-oblong, as long as stipe, 25-30 cm wide at base, apex acuminate; pinnae 7-10 pairs, alternate, stalked, spreading, broadly lanceolate, basal pinnae as large as second basal pinnae, up to 18 × 6-7 cm at base, apex acuminate; pinnules 8-10 pairs, subopposite, spreading, oblong-lanceolate, basal pinnules larger, 3-4 × ca. 1.5 cm, base asymmetrical, acroscopically auriculate, truncate, parallel to rachis, basiscopically cuneate and decurrent to costa, pinnatilobate to pinnatifid, apex acuminate; pinnule lobes subdeltoid, margin serrate; veins prominent, pinnate, simple or forked. Lamina papery, glabrous on both surfaces. Sori linear, 3 or 4 pairs per lobe, single or double on basal acroscopic veinlets, nearly reaching lobe margin; indusia gray-brown, linear, membranous, persistent.

● Forests; ca. 2100 m. Gansu (Tielouhanlingou, Wenxian).