大叶耳蕨 da ye er jue

Polystichum grande Ching, Bull. Fan Mem. Inst. Biol. 2: 189. 1931, not Fée (1857); P. kiusiuense Tagawa.

Plants evergreen. Rhizome erect or ascending, short, densely covered with linear grayish brown scales. Fronds up to 1 m; stipe stramineous, 26-40 cm, 5-7 mm in diam. at base, densely covered with linear or lanceolate, grayish brown scales and larger scales; large scales grayish brown, ovate-lanceolate and broadly lanceolate, up to 12 × 4 mm, subentire or with few small teeth, caudate or long acuminate. Lamina bipinnate, oblong, 33-73 × 20-31 cm at middle, slightly contracted toward base, basal part fertile, apex acute, fertile; rachis without proliferous bulbils, covered with linear or lanceolate grayish brown scales and larger scales; large scales dense, ovate-lanceolate to broadly lanceolate, up to 7 × 2.5 mm, margins fimbriate, apices long acuminate. Pinnae 9-15 pairs, opposite or nearly opposite, ascendant, shortly stalked, oblong-lanceolate, gradually contracted toward base, apex caudate, middle pinnae 11-17 × 2.5-3.2 cm, 1-pinnate; costa densely covered with linear grayish brown scales. Pinnules 15-17 pairs, alternate, shortly stalked, falcate-oblong, bases cuneate, acroscopic margins subentire, with deltoid auricles, apices acute; abaxially with dense lanceolate microscales, adaxially with few microscales; frond texture thinly leathery; venation pinnate on pinnules, lateral veins 6-9 pairs, dichotomous, distinct. Sori 8-11 pairs per pinnule, grayish brown, large, in 1 row on each side of midrib or more on acroscopic side, terminal on veinlets, exindusiate. 2n = 164.

Broad-leaved forests; 500-2300 m. Guangxi (Yaoshan), Guizhou (Duyun), Taiwan (Yilan), S Yunnan [Japan (Kyushu)].

Polystichum squarrosum in Y. C. Wu et al. (Bull. Dept. Biol. Sun Yatsen Univ. 3: 86, t. 34. 1932) is a misidentification of P. grandifrons.

Its distribution in India as reported by Fraser-Jenkins (Aspects Pl. Sci. 13: 263. 1991) and Chandra et al. (Taiwania 53: 170-209. 2008) is doubtful.

Polystichum grandifrons has acute lamina apex and rachis scales with fimbriate margins and is exindusiate.