3. Asplenium speluncae Christ, Bull. Acad. Int. Géogr. Bot. 13: 113. 1904.
黑边铁角蕨 hei bian tie jiao jue
Plants 4-8 cm tall. Rhizome erect, short, apex scaly; scales blackish brown, iridescent, narrowly triangular to subulate, entire. Fronds simple, tufted; stipe purplish black, shiny, 5-12(-20) mm, terete, with scales when young, subglabrous when old; lamina elliptic to narrowly triangular, 3-6(-8.5) × 1.2-1.7(-2) cm, base broadly cuneate to truncate, margin entire to undulate and with narrow black edge, apex obtuse. Rachis or midrib distinct abaxially, black and shiny; veins obscure, oblique, 2(or 3)-forked. Fronds leathery, adaxially olive-green when dry, brown abaxially. Sori linear, 3-6 mm, medial between midrib and margin; indusia grayish brown, linear-elliptic, thinly papery, entire and with narrow purple edge, opening toward midrib, persistent. Spores with cristate-alate perispore.
● In limestone crevices, forests; 1100-1400 m. Guangdong, Guangxi, Guizhou, Hunan, Jiangxi.
Asplenium speluncae is a particular and distinct species. Hybrids with A. normale were probably described from Hunan as A. ×xianqianense C. M. Zhang (Keys Vasc. Pl. Wuling Mts. 568. 1995, pro sp.) but are also known from Guangxi.