长镰羽耳蕨 chang lian yu er jue

Plants evergreen. Rhizome ascending, short, 1.5-2 cm in diam. including stipe bases, rhizome apex and stipe base scaly; scales brown, ovate-lanceolate, up to 5 mm, membranous, with few fine teeth. Fronds 2-6 per rhizome, 25-60 cm; stipe stramineous, 8-25 cm, 1-2 mm in diam. at base. Lamina 1-pinnate, adaxially dark green and abaxially light green when dry, lanceolate or narrowly elliptic-lanceolate, 15-40 × 4-9 cm at middle, bases broadly rounded, apices pinnatifid and long acuminate; rachis stramineous, without proliferous bulbils, adaxially sparsely scaly; scales appressed, brown or dark brown, ovate, membranous, peltate, toothed, caudate with long acute tips. Pinnae 10-30 pairs, slightly ascendant, slightly curved upward and falcate-lanceolate, middle pairs 2-5 cm, 1-1.5 cm wide at base, lower pairs below middle of lamina gradually contracted or only slightly contracted, bases obviously asymmetrical, acroscopic base with deltoid or semicircular auricles, proximal margins of auricles nearly parallel to rachis or often overlapping rachis, acroscopic margins near auricles slightly biserrate, basal basiscopic margins narrowly cuneate, lower part of basiscopic margins curved, margins entire, distal basiscopic margins curved upward, toothed, teeth spinulose apically and often slightly recurved, apices acuminate; adaxially glabrous, abaxially sparsely scaly; microscales appressed, brown, lanceolate or with long caudate tips, membranous, margins toothed; frond texture leathery; venation pinnate, slightly distinct abaxially, indistinct adaxially; lateral veins pinnate above midrib from base to apex, dichotomous or simple, simple or dichotomous below midrib; veinlets not reaching pinna margin. Sori small, often limited to upper lamina, in 1 row on each side of midrib, close to margins, up to 30, lower part of pinnae below midrib sterile; indusia present, small, subentire, caducous.

● Wet sandstone crevices by streams, montane broad-leaved evergreen forests; 1000-1600 m. Chongqing (Jiangjin), N Guizhou (Chishui, Xishui), S Sichuan, NE Yunnan (Suijiang).

Polystichum falcatilobum is similar to P. formosanum, but its lamina is leathery, its veins are indistinct, its pinnae are longer and long falcate-lanceolate, and its microscales are lanceolate or ovate, caudate apically, toothed on the margins, appressed, and brown.