173. Polystichum oblanceolatum H. He & Li Bing Zhang, Novon. 22: 160. 2012.
倒披针耳蕨 dao pi zhen er jue
Plants evergreen, (2.8-)6.5-9.5 cm tall. Rhizome erect, ca. 4.25 mm, ca. 2.7 mm in diam., up to 4.3 mm in diam. with bases of remnant old stipes, sparsely scaly; scales dark brown, lanceolate, ca. 0.7 × 0.12 mm, entire; roots dull brown when dry, up to 11.5 cm, 0.2-0.35 mm in diam. Fronds 5-12 fronds tufted around rhizome, (2.7-)6.3-9.4 cm; stipe stramineous, 0.8-1.4 cm, 0.65-0.98 mm in diam. at middle, moderately scaly; scales on basal stipe dark brown with narrow lighter-colored margins when fresh, but becoming entirely brown when dry, deltoid-lanceolate, 1.42-1.69 × 0.51-0.68 mm, papery, margins subentire, apices subulate; scales on distal stipe similar but thinner and narrower, brown, up to 1.61 × 0.37 mm, thinly papery, margins mostly with small irregular dentate outgrowths especially below, apices subulate. Lamina 1-pinnate, adaxially shiny green when fresh, dull stramineous when dry, abaxially paler and dull, oblanceolate, (2.3-)4.5-8.5 × 0.9-1.7 cm, gradually narrowed toward base from below middle, apex acute or shortly acuminate; rachis green (same color as pinnae) when fresh, turning stramineous when dry, 0.51-0.69 mm in diam. at middle, apex without proliferous bulbils, abaxially sparsely scaly; rachis scales pale brown, linear-lanceolate, 0.70-1.41 mm, base 0.10-0.25 mm wide, varying in size, thinly papery, margins entire, apices subulate. Pinnae (5-)10-16 pairs, 4.45-7.82 × 2.95-4.57 mm, upper middle ones approximate or slightly imbricate, firmly papery, shortly stalked, (stalk 0.3-0.8 mm), at angles of 70°-90° with rachis, alternate, basal 1-3 pairs nearly fan-shaped, base rounded to broadly cuneate with acroscopic side slightly wider, distally repand or with 3-5 broad teeth, teeth occasionally shortly mucronate, upper pairs mostly oblong but asymmetrical, acroscopic sides much broader and slightly auriculate at base, both acroscopic and basiscopic bases substraight and forming a ± right angle at base of pinna, apices acute, distal acroscopic side repand or with 3 wavelike teeth, distal basiscopic side mostly with 1 or 2 short broad teeth; adaxially glabrous, abaxially sparsely covered with microscales along veinlets; microscales brown, linear, 0.35-0.55 × 0.01-0.07 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-)3-4(-6) in 1 row on acroscopic side, usually 1 sorus on distal basiscopic side, 0.70-1.25 mm in diam., 0.55-1.12 mm apart, submarginal, center of sorus 0.3-1.1 mm from pinna margin; indusia pale brown, ca. 0.8 mm in diam., membranous, irregularly lacerate. Sporangia dark brown when mature, almost orbicular, ca. 0.29 mm in diam., walls ca. 0.018 mm thick; annuli with 11-14 thickened cells; stalks ca. 0.35 mm.
● Weathered crust of limestone rocks on floors of karst caves; ca. 900 m. N Guangxi (Tiane).