贵州复叶耳蕨 gui zhou fu ye er jue

Polystichum nipponicum Rosenstock, Repert. Spec. Nov. Regni Veg. 13: 190. 1914; Arachniodes anshunensis Ching & Y. T. Hsieh; A. gongshanensis Ching & Y. T. Hsieh; Byrsopteris nipponica (Rosenstock) Sa. Kurata; Polystichopsis nipponica (Rosenstock) Tagawa; Rumohra nipponica (Rosenstock) Ching.

Rhizome creeping, succulent at growing apex, 1-2.5 cm in diam., densely scaly; scales pale or reddish brown, ovate-lanceolate or lanceolate, to 7 × 1-2.5 mm, apically attenuate, thin and soft. Fronds remote or proximate, 0.7-1.5 m; stipe ochraceous or amber, 36-75 cm, 4-8 mm in diam., base scaly as rhizome, upward scales diminishing to glabrescent; lamina 3(or 4)-pinnate, lustrous yellowish green when dried, oblong-lanceolate or ovate-oblong, 40-75 × 25-45 cm, often thickly papery and flexible, base rounded-cuneate, apex acuminate or slightly attenuate, rachis glabrescent; pinnae 6-8(-10) pairs, alternate or lowest 1 or 2 pairs opposite, with to 2 cm stalk, obliquely spreading; lowest pinnae deltoid-lanceolate, 18-35 × ca. 10 cm, base rounded-cuneate, apex acuminate; primary pinnules 12-17 pairs, proximal ones with to 8 mm stalk, lanceolate, (basal basiscopic one 6-8 × 2-3 cm), base rounded-cuneate, apex acuminate, larger fronds with proximal 1-3 pairs of primary pinnules 2-pinnate; secondary pinnules shortly stalked or sessile, oblong, ca. 1.5 × 0.7 cm, base cuneate, apex acute, margin sharply dentate or pinnatifid, with mucronate teeth; upper pinnae gradually reduced; axes and veins of ultimate segments with brown, appressed, articulate hairs, and with a few minute brown ovate-based or linear scales abaxially. Sori terminal on veinlets, 2 or 3 pairs per ultimate segment, medial between midvein and margin; indusia pale brown, membranous, and entire.

Slopes by streams in broad-leaved forests or in shaded valleys, sometimes in coniferous forests or bamboos; 700-2300(-2800) m. Chongqing, Guangdong, Guizhou, Hunan, Jiangxi, Sichuan, Yunnan, Zhejiang [Japan].

Specimens from Guizhou and Yunnan are much larger in size than Japanese ones, and plants distributed in Yunnan occur at ca. 1000 meters higher in elevation.