177. Polystichum oblongum Ching ex W. M. Chu & Z. R. He, Fl. Reipubl. Popularis Sin. 5(2): 228. 2001.
镇康耳蕨 zhen kang er jue
Plants evergreen. Rhizome erect, short, rhizome apex and basal stipe scaly; scales reddish brown, lanceolate, membranous, margins long fimbriate. Fronds 5-12 cm; stipe stramineous, short and slender, shorter than 2 cm, less than 1 mm in diam. Lamina dark brownish green when dry, narrowly elliptic-lanceolate, up to 10 × 1.5 cm, gradually contracted below middle, 1-pinnate, apex pinnatifid and shortly obtuse, with only 3-5(or 6) lobes; rachis stramineous, without proliferous bulbils, abaxially covered with a few lanceolate brown scales. Pinnae fewer than 20 pairs, approximate or slightly imbricate, alternate, oblong, shortly stalked, up to 7 × 5 mm, apices obtuse, truncate, or rounded-truncate; acroscopic margins with few (no more than 5) repand obtuse teeth, acroscopic base auriculate, auricles with obtuse tips, proximal margins truncate, parallel to rachis, basiscopic margins narrowly cuneate, nearly vertical to rachis, often ± curved inward, apices with 1-3 repand and obtuse teeth; both surfaces glabrous; frond texture thinly papery; venation pinnate, slightly distinct abaxially, inconspicuous adaxially; lateral veins dichotomous or simple, not reaching pinna margin, 3-5 on acroscopic side, only 1 or 2 on basiscopic side. Sori small, nearly medial on each side of pinna, slightly close to pinna margin, 1-5 terminal on veinlets; indusia present, dark brown, small, thickly membranous, coarsely lobed.
● Rock crevices in dense Quercus forests; ca. 2000 m. SW Yunnan (Zhenkang).
Polystichum oblongum is similar to P. jinfoshanense, but its scale margins are long fimbriate and its pinnae are thinly papery with a few obtuse teeth on the margin.