凤山耳蕨 feng shan er jue

Plants evergreen. Rhizome ascending, 0.5-1.3 cm, ca. 3 mm in diam. or ca. 7 mm in diam. with remnant bases of old stipes, sparsely scaly; scales brown, ovate-deltoid or lanceolate, ca. 0.2 × 0.5 mm, entire; roots dull brown when dry, up to 16 cm, 0.2-0.3 mm in diam., subglabrous or densely covered with short and linear tortuous hairs. Fronds 8-17 per rhizome, appressed to substrate or slightly ascending, (2.5-)4.3-18 cm; stipe green, (0.7-)1.5-3.5 cm, 0.25-0.45 mm in diam. at middle, densely scaly; basal stipe scales dark brown, concolorous, lanceolate or subulate, 0.7-3.5 × 0.28-0.43 mm, papery, margins with ca. 0.07 mm irregular dentate outgrowths, apices caudate; distal stipe scales similar to basal stipe scales but narrower, dark brown, up to 2.5 × 0.35 mm, papery, margins with short outgrowths, apices caudate. Lamina 1-pinnate, adaxially shiny green when fresh, dull green when dry, oblanceolate, (2.1-)3.5-18 × 0.9-2.5 cm, gradually narrowed toward base from below middle of lamina, acute or rounded; rachis green (same color as pinnae) when fresh, turning yellowish green when dry, 0.59-0.71 mm in diam. at middle, apex without proliferous bulbils, abaxially densely scaly; rachis scales dark brown or lighter, subulate, 2.1-4.6 mm, base 0.35-0.61 mm wide, differing in length, papery, sparsely toothed, caudate. Pinnae (4-)8-24 pairs, oblong, 4.9-13 × 3-7 mm, basalmost pairs nearly fan-shaped and 1/4-1/3 as long as middle ones, approximate, sessile or almost so, basiscopic margins at 100°-120° angles with rachis, alternate, apices rounded or acute, not mucronate, bases broadly cuneate with basiscopic side wider and forming an 80° angle with acroscopic side, distal acroscopic margins shallowly undulate or almost entire, undulations 4, ca. 0.4 mm tall at middle and non-mucronate, acroscopic base auriculate; auricles rounded or slightly deltoid, 1.1-1.4 × 2.4-2.8 mm; basiscopic margins entire, curved; adaxially almost glabrous, abaxially dull and slightly paler, sparsely covered with microscales; microscales narrow-type, brown, linear or subulate, 0.35-1.1 × 0.07-0.18 mm at base; frond texture papery; venation pinnate, visible abaxially, slightly obscure adaxially; lateral veins free, simple or forked. Sori terminal on lateral veins, 1-4 on acroscopic side, 0-2 on distal basiscopic side, 1.4-2.4 mm in diam., close to midrib (centers of sori 0.88-1.4 mm (small individuals) to 0.9-3.1 mm (large individuals) from midrib, 0.95-2.3 mm from pinna margin), centers ca. 2.1 mm apart from one another; indusia brownish, (0.7-)1.2-1.5 mm in diam., irregularly lacerate. Sporangia orbicular, ca. 0.28 mm in diam., walls ca. 0.018 mm thick, dark brown when mature; annuli with ca. 15 thickened cells; stalks ca. 0.32 mm. Spores elliptic or slightly trapezoid in equatorial view; perispore sculpturing granulate with blunt folds.

● Wet weathered soil on cave walls, stalagmites, limestone crevices inside caves; (400-)500-700(-800) m. N Guangxi (Bama, Fengshan).