189. Polystichum yuanum Ching, Icon. Filic. Sin. 5: t. 235. 1958.
倒叶耳蕨 dao ye er jue
Plants evergreen. Rhizome erect, or slightly ascending, short, together with stipe base 1-2.5 cm in diam., rhizome apex and stipe densely scaly; scales dark brown, up to 4 mm, membranous, margins with irregular ciliate teeth, apices rounded-acuminate. Fronds 12-38 cm; stipe stramineous or pale greenish stramineous, 1-15 cm, ca. 1 mm in diam., distal stipe scales mostly caducous. Lamina 1-pinnate, light brown or light brownish green, adaxially darker, narrowly elliptic-lanceolate, 8-30 × 1.8-3.5 cm at middle, 1.3-2 cm wide at base, slightly contracted below middle, long acuminate; rachis stramineous or light green stramineous, without proliferous bulbils, sparsely scaly abaxially, especially on pinna bases; scales dark brown, ovate or lanceolate, with sparse irregular long teeth. Pinnae 20-30 pairs, often alternate, sometimes nearly opposite, often remote, rarely contiguous or hardly imbricate, very shortly stalked, mostly ± reflexed, rarely attached at right angles or nearly so with rachis above middle, oblong, middle pinnae 8-15 × 5-7 mm, basal pinnae 5-10 × 4-6 mm, apices acute, bases asymmetrical, acroscopic side much wider, acroscopic margins nearly truncate, base widest and with 1 acute weakly spinulose auricle, margins of auricles with sparse, unequally sized, shallow teeth, tips of teeth obtuse, basal basiscopic margins narrowly cuneate, truncate or slightly recurved, margins entire, distal part of basiscopic margins nearly obliquely truncate and with 2-4 shallowly spinulose teeth; adaxially glabrous, abaxially sparsely covered with microscales, microscales light brown, ovate-lanceolate or lanceolate or hairlike; frond texture papery; venation pinnate, distinct abaxially, slightly distinct adaxially; lateral veins not reaching pinna margin, pinnate above pinna midrib from base upward, dichotomous or simple, simple or dichotomous below pinna midrib. Sori small, terminal on shorter veinlets of upper pinnae from middle of lamina upward, close to pinna margin; indusia present, dark brown, entire, caducous.
● Rock crevices in limestone valleys in broad-leaved forests and mixed broad-leaved coniferous forests; 2200-2900 m. NW Yunnan (Zhongdian).