柔软耳蕨 rou ruan er jue

Aspidium lentum D. Don, Prodr. Fl. Nepal. 4. 1825; A. auriculatum (Linnaeus) Swartz var. lentum (D. Don) C. B. Clarke; A. auriculatum var. subbipinnatum Hooker; Polystichum auriculatum (Linnaeus) C. Presl var. lentum (D. Don) Beddome; P. auriculatum var. subbipinnatum (Hooker) Beddome; P. longipes Ching & S. K. Wu (1983), not Maxon (1909); P. medogense Ching & S. K. Wu.

Plants evergreen. Rhizome erect, short, densely covered with large scales; scales narrowly ovate or ovate-lanceolate, middle part thickened, castaneous, with broad brown margins, densely serrulate. Fronds 40-100 cm; stipe stramineous, light brown, or light purple, 10-30 cm, 1.5-3 mm in diam., base densely covered with large scales similar to rhizome scales, mixed with brown small scales; small scales lanceolate to linear-lanceolate, toothed; upper stipe with few small scales similar to basal small scales. Lamina deeply or shallowly bipinnatifid or bipinnatipartite, light green abaxially, darker adaxially when dry, sometimes white along midribs, narrowly lanceolate, 30-70 × 5-10 cm at middle, base slightly contracted, apex attenuate; rachis and pinna bases sparsely covered with small scales; small scales brown, lanceolate or linear-lanceolate, with 1 proliferous bulbil near rachis tip, bulbil densely covered with brown scales. Pinnae 25-40 pairs, alternate or nearly opposite, lower pairs reflexed toward base, middle pinnae attached at right angles to rachis, upper pairs attached at right angles to rachis or slightly ascendant, lanceolate or falcate, middle pinnae 3-5 × 1.3-1.5 cm above base, both surfaces glabrous, bases shortly stalked and asymmetrical, apices acute with mucronate tips; basiscopic side cuneate, acroscopic base auriculate, auricles parallel to rachis, pinnatilobate to pinnatipartite on both acroscopic and basiscopic margins, bases nearly pinnatipartite to midribs; lobes of middle pinnae 5-10 pairs, ascendant, nearly elliptic, with few slender, acute teeth, mucronate; lobes of acroscopic bases obviously largest, nearly free, oblong, toothed or incised or subentire; frond texture thinly leathery; veins indistinct on both surfaces, pinnate on lobes, veinlets mostly free, often forked on auricles. Sori 1-4 per lobe, up to 6 per auricle; indusia brown when mature, small, caducous.

On rocks in montane broad-leaved evergreen forests; 800-1600 m. Xizang (Mêdog) [Bhutan, NE India, Nepal].