单叶对囊蕨 dan ye dui nang jue

Asplenium lanceum Thunberg, Fl. Jap. 333. 1784; A. subsinuatum Wallich ex Hooker & Greville; Athyrium dubium (D. Don) Ohwi (1956), not Ching (1949); A. lanceum (Thunberg) Milde (1870), not T. Moore (1860); Diplazium lanceum (Thunberg) C. Presl (1836), not Bory (1833); D. simplicifolium Kodama; D. subsinuatum (Wallich ex Hooker & Greville) Tagawa; Micropodium lanceum (Thunberg) J. Smith; Scolopendrium dubium D. Don; Triblemma lancea (Thunberg) Ching.

Rhizome slender, with black or brown, lanceolate scales; frond caespitose. Fertile frond up to 40 cm; stipe pale gray, 8-15 cm, base with brown scales; lamina lanceolate or linear-lanceolate, 10-25 × 2-3 cm, gradually narrowed to both ends, entire or slightly repand at margin; midrib prominent on both surfaces; veinlets ascending, 3-4 per vein, parallel, reaching margin. Lamina papery or subleathery. Sori widespread throughout lamina except in basal part, linear, single or occasionally double, medial; indusia pale brown, membranous. Spores reniform in equatorial view, perispore thin and hyaline, with irregularly thickly aculeate or clavate processes.

Often in acidic soils, on rocks in forests; 200-1600 m. Anhui, Fujian, Guangdong (and islands), Guangxi, Guizhou, Hainan, Henan, Hunan, Jiangsu, Jiangxi, Sichuan, Taiwan, Yunnan, Zhejiang [India, Japan, Myanmar, Nepal, Philippines, Sri Lanka, Vietnam].