Aspidium discretum D. Don, Prodr. Fl. Nepal. 4. 1825; Polystichum aculeatum (Linnaeus) Roth ex Mertens var. nigropaleaceum Christ; P. fuscopaleaceum Alston; P. indicum Khullar & S. C. Gupta; P. kathmanduense Nakaike; P. lobatum (Hudson) C. Presl var. discretum (D. Don) C. Christensen; P. nigropaleaceum (Christ) Diels; P. setiferum (Forsskål) Moor ex Woynar var. crenatum N. C. Nair; P. setiferum var. fuscopaleaceum (Alston) Schelpe; P. setiferum var. nigropaleaceum (Christ) Sledge.

Plants evergreen. Rhizome erect or ascending, short, densely covered with linear brown scales. Fronds 30-90 cm; stipe brown, 13-40 cm, ca. 4 mm in diam. at base, sparsely scaly; scales brown to dark brown, linear. Lamina bipinnate, oblong to deltoid-ovate, 24-70 × 10-35 cm at middle, often 20 cm, lower part slightly contracted, base fertile, apex acuminate or slightly acute, sterile; rachis without proliferous bulbils, abaxially scaly; scales dark brown to blackish brown, linear, twisted. Pinnae 12-26 pairs, alternate, slightly ascendant, lanceolate, lower part not contracted, asymmetrical at base, shortly stalked, middle pinnae 12-17 × 2.6-3.5 cm, 1-pinnate, caudate or acuminate; costa adaxially sulcate, abaxially scaly; scales dark brown to blackish brown, linear, twisted. Pinnules 12-35 pairs, alternate, shortly stalked, oblong, 0.9-2.2 × 0.5-0.8 cm, bases cuneate, acroscopic bases with rounded auricles, margins deeply toothed or lobed, apices acute, apices of most lobes obviously spinulose; basal acroscopic pinnules largest, pinnatilobate; abaxially with few shortly filiform microscales, adaxially subglabrous; frond texture papery; venation pinnate, lateral veins 5-8 pairs, dichotomous, distinct. Sori (3-)5-8 pairs per pinnule, in 1 row on each side of midrib, terminal on veinlets; indusia present, irregularly lacerate. 2n = 82.

Forests; 1700-2900 m. Xizang (Mêdog, Nyingchi), Yunnan [Bhutan, India, Kashmir, Myanmar, Nepal, Pakistan, Thailand].