川渝耳蕨 chuan yu er jue

Polystichum omeiense Christ, Bull. Acad. Int. Géogr. Bot. 16: 114. 1906, not C. Christensen (1905).

Plants evergreen. Rhizome erect, short, ca. 1.5 cm in diam. including stipe bases. Fronds few, 40-80 cm; stipe stramineous, 15-30 cm, 1-2 mm in diam. at base; distal stipe and rachis sparsely scaly; scales appressed, dark brown, broadly ovate or ovate-lanceolate, membranous, apex long caudate. Lamina bipinnate, light green on both surfaces when dry, elliptic-lanceolate, 23-45 × 5-9 cm, contracted at base, acuminate; rachis stramineous, without proliferous bulbils, abaxially sparsely scaly; scales light brown, lanceolate. Pinnae 26-31 pairs, falcate-lanceolate, up to 5 × 1 cm at middle, bases obviously asymmetrical, acroscopic margins truncate, basiscopic margins narrowly cuneate, margins of pinnae pinnatilobate to pinnatisect, apices acuminate. Pinnules 10-13 pairs, basal acroscopic pinnules obviously largest, slightly auriculate, elliptic, bases cuneate, margins toothed and spinulose; other lobes ascendant, elliptic, apex curved upward, upper part lobed and forming 2-4 secondary lobes, few basal basiscopic lobes often smaller, apices acute and spinulose; adaxially glabrous, abaxially densely covered with fibrillose light brown microscales; frond texture papery; venation pinnate to dichotomous or simple on primary lobes. Sori small, ca. 1 mm in diam., abaxial or terminal on veinlets, located between midrib and pinnule margins; indusia present, dark brown, thickly textured, entire, evanescent.

● Wet limestone crevices in broad-leaved evergreen forests in valleys; 700-900 m. Chongqing (Jinfo Shan), Sichuan (Emei).

The description of Polystichum bissectum in FRPS (5(2): 171. 2001) is incorrect.