对马耳蕨 dui ma er jue

Aspidium tsus-simense Hooker, Sp. Fil. 4: 16. 1862; A. aculeatum (Linnaeus) Swartz var. pallescens Franchet; Polystichum falcilobum Ching; P. tsus-simense var. pallescens Franchet; P. tsus-simense var. parvipinnulum W. M. Chu.

Plants evergreen. Rhizome erect, densely scaly; scales dark brown, narrowly lanceolate. Fronds 30-60 cm; stipe stramineous, 16-30 cm, 2-4 mm in diam. at base, lower part densely scaly; scales blackish brown, lanceolate and linear, upper scales gradually linear, margins ciliate. Lamina broadly lanceolate or narrowly ovate, 20-42 × 6-14 cm, rounded-cuneate or truncate, bipinnate at lower part, long acuminate or caudate; rachis without proliferous bulbils, densely scaly abaxially; scales blackish brown or brown, linear with dilated base, margins ciliate. Pinnae 20-26 pairs, alternate, attached at right angles to rachis or slightly ascendant, shortly stalked, linear-lanceolate, middle pairs 4-9 × 1-1.5 cm, bases oblique, acroscopic margins truncate, basiscopic margins broadly cuneate, pinnate, apices acuminate to caudate. Pinnules 7-13 pairs, alternate, strongly ascendant, approximate, shortly stalked, obliquely rounded, obliquely ovate or deltoid-ovate, lower pairs 5-10 × 4-6 mm, apex acute or obtuse, mucronate; basal acroscopic pinnule largest, ovate or deltoid-ovate, 7-15 × 4-6 mm, sometimes pinnatifid; abaxially with few microscales; microscales yellowish brown, filiform with dilated bases; frond texture thinly leathery; venation pinnate on pinnules, lateral veins often forked, abaxially slightly concave or raised, adaxially indistinct. Sori in 1 row on each side of pinnule midrib, 3-9 per pinnule; indusia present, entire.

Broad-leaved evergreen forests, shrubs; 200-3400 m. Anhui, Fujian, S Gansu, Guangxi, Guizhou, Henan (Xixia), Hubei, W Hunan, Jiangxi, Jilin (Mopan Shan), S Shaanxi, Shandong, Sichuan, Taiwan, E and S Xizang, Yunnan, Zhejiang [N and NW India, Korea, Japan, Vietnam].

Roux (Bull. Nat. Hist. Mus. London, Bot. 30(2): 33-130. 2000) treated Polystichum tsus-simense as a synonym of P. luctuosum (Kunze) T. Moore from Africa.