锯鳞耳蕨 ju lin er jue

Polystichum lentum (D. Don) T. Moore var. gelida Rosenstock; P. rectipinnum Hayata.

Plants evergreen. Rhizome ascending, short. Fronds 40-60 cm, nearly dimorphic, fertile fronds smaller; stipe amber, 13-23 cm, 1-1.5 mm in diam. at base, whole plant with large and small scales; all scale margins densely serrulate, teeth brown to dark brown, irregular, often forked or irregularly pinnately branched; large scales brown, ovate or ovate-lanceolate, up to 1 cm × 4 mm, thickly membranous, or middle part thickened and blackish castaneous, with broad brown margins; small scales brown to dark brown, lanceolate, apices long caudate or linear-subulate. Lamina 1-pinnate to bipinnatifid, broadly lanceolate, base slightly or not contracted, apex attenuate; sterile lamina up to 30 × 12 cm; fertile lamina up to 16 × 6 cm; rachis stramineous, abaxially densely scaly; scales brown or blackish castaneous, lanceolate or narrowly lanceolate, basiscopic margins with few long teeth; sometimes with 1 proliferous bulbil near rachis tip, bulbil densely covered with brown scales. Pinnae 8-20 pairs, green or yellowish green when dry, darker abaxially, acuminate; middle pinnae attached at right angles to rachis or slightly reflexed toward base, lanceolate, apices acuminate or acute; acroscopic base auriculate, basiscopic base cuneate, pinnatifid to pinnatilobate on both sides, margins of upper pairs of pinnae with only coarse and shallow teeth, sometimes acroscopic bases of basal 1-3 pairs of pinnae nearly pinnatisect, pinnae of sterile fronds larger, up to 6 × 1.5 cm; pinnae of fertile fronds up to 3 × 1 cm; lobes obliquely deltoid, with 1-5 acute teeth, auricles often slightly curved toward rachis; pinna midribs and abaxial surface of veins covered with numerous microscales; microscales light brown, subulate or narrowly lanceolate, membranous; frond texture thinly leathery; venation pinnate on lobes, midribs conspicuous adaxially, concave; lateral veins slightly visible abaxially, indistinct adaxially; veinlets free, veinlets on auricles dichotomous. Sori small, abaxial on veinlets, close to midrib, 1-5 on each group of lateral veins, up to 9 per auricle; indusia light brown when mature, shallowly lobed, caducous. Spores semi-orbicular in equatorial view; perispore sculpturing with finely reticulate ornamentation.

● On shaded rocks in montane cloud forests and Cunninghamia lanceolata forests; 2000-2400 m. Taiwan, SC Yunnan.

Polystichum prionolepis has special, densely serrulate scales with teeth often forked or irregularly branched pinnately. The specific epithet "prionolepis" (toothed scales) refers to this characteristic.