169. Polystichum dangii P. S. Wang, Pterid. Fl. Guizhou. 531. 2001.
成忠耳蕨 cheng zhong er jue
Polystichum mulunense X.L.Shen & R.H.Jiang, Pl. Diversity Resources 37(6): 737. 2015.
Plants evergreen. Rhizome erect, short, 2-4 cm in diam. including stipe bases, upper part densely scaly; scales black or blackish brown, shiny, broadly lanceolate, 3-5 × 0.6-0.8 mm at base, papery, with few short teeth, caudate. Fronds 8-22 cm, sometimes only 5 cm under dry conditions; stipe stramineous, 1-4 cm, 1-2.5 mm in diam., densely scaly; scales black or blackish brown, shiny, lanceolate and linear, with few short teeth, caudate. Lamina 1-pinnate, light green when dry, adaxially darker, shiny, lanceolate or oblong, 2.5-13 × 1.6-3.7 cm at middle, base not or slightly contracted, apex obtuse; rachis light stramineous, without proliferous bulbils, sparsely scaly; scales dark brown or black, lanceolate, margins sparsely toothed. Pinnae 5-21 pairs, sessile, usually approximate or imbricate, alternate, basiscopic margins forming 45°-80° angles to rachis, most pinnae ± angled basiscopically, oblong or obliquely oblong, middle pairs largest, 1-1.5 cm, 5-9 mm, bases asymmetrical, acroscopic base nearly non-auriculate or slightly curved, proximal acroscopic margins of pinnae truncate, parallel to rachis, distal part of acroscopic margins truncate, basal basiscopic margins cuneate, truncate or curved, distal basiscopic margins curved, margins of pinnae entire, apices obtuse; adaxially glabrous, abaxially sparsely covered with dark brown, linear microscales; frond texture leathery; venation indistinct abaxially, distinct adaxially, pinnate, lateral veins dichotomous or simple. Sori large, on distal part of pinnae, lower pinnae sterile, terminal on shorter veinlets, close to pinna margin, up to 4 above midrib, 0-3 below middle midrib; indusia brown, small, repand, evanescent.
● Wet or dry limestone crevices and walls, around cave mouths; 700-800 m. N Guangxi (Huanjiang), S Guizhou (Libo).