长根假毛蕨 chang gen jia mao jue

Nephrodium canum Baker in Hooker & Baker, Syn. Fil. 267. 1867; Cyclosorus canus (Baker) S. Lindsay; Dryopteris cana (Baker) Kuntze; D. repens C. Christensen; N. repens C. Hope (1899), not Baillon (1874); Pseudocyclosorus medogensis Ching & S. K. Wu; P. repens (C. Christensen) Ching; Thelypteris cana (Baker) Ching; T. repens (C. Christensen) Ching.

Plants more than 1 m tall. Rhizomes suberect and subglabrous. Fronds clustered; stipes 15-20 cm, stramineous or brownish, with sparse brown scales and dense setae; laminae oblong-lanceolate, 40-80 × 13-25 cm, pinnatifid-acuminate at apices; proximal pairs of pinnae reduced and hastate or auriculate; normal pinnae 20-25 pairs, alternate, sessile, spreading, pinnate-pinnatifid; middle pinnae narrowly lanceolate, pinnatifid and long acuminate; proximal pair of segments slightly elongate, spreading, 7-14 × 1.6-2.4 cm, pinnatifid nearly to costae; segments 20-28 pairs, subligulate, slightly bent, 7-12 × 2.5-4 mm, entire, acute. Veins raised on both sides, visible, 8-12 pairs of veinlets per segment, proximal pair arising from bases or above base of costules, acroscopic vein reaching bottom of sinus, basiscopic one reaching margin above sinus. Laminae thinly papery or herbaceous, dark green or greenish when dry; abaxial sides of rachises, costae, and veins all with acicular hairs, adaxially with dense appressed setae along grooves, sparsely setaceous along veins, shortly hairy on intercostal areas on both surfaces. Sori orbicular, attached on middle veinlets; indusia orbicular-reniform, brown, persistent, hairy.

Broad-leaved forests on mountain slopes; 900-2800 m. SE Xizang (Mêdog) [Bhutan, N India, Kashmir, Nepal].

"Pseudocyclosorus pectinatus" (Ching ex K. H. Shing, Vasc. Pl. Hengduan Mount. 1: 98. 1993 ["pectinata"]) is conspecific with P. canus but was not validly published because no Latin description or diagnosis, or reference to such, was provided (Melbourne Code, Art. 39.1).