武陵山耳蕨 wu ling shan er jue

Plants evergreen. Rhizome erect, short, including stipe base densely scaly; scales brown, ovate, thickly membranous, margins subentire. Fronds 13-20 cm; stipe stramineous, 2-6 cm, ca. 1 mm in diam., distal stipe scales similar to basal stipe scales but smaller and sparser, appressed. Lamina 1-pinnate, grayish green when dry, narrowly lanceolate, 11-14 × 1.6-1.8 cm at middle, slightly gradually contracted below middle, apex pinnatifid and acuminate; rachis stramineous, without proliferous bulbils, sparsely scaly abaxially; scales brown, ovate or ovate-lanceolate, membranous, sparsely toothed. Pinnae ca. 20 pairs, approximate, alternate, midribs attached at right angles to rachis or slightly ascendant, shortly stalked, reflexed, oblong, apices acute, pointing downward; acroscopic base auriculate or rounded, auricles nearly semicircular, with 1 or 2 sharp, shortly spinulose teeth, proximal margins of auricles slightly curved, overlapping or sometimes nearly parallel to rachis, basiscopic margins recurved, margins entire, basal basiscopic margins cuneate, distal basiscopic margins and whole acroscopic margins (including auricle margins) serrate or biserrate and with 8-10(or 11) sharp teeth; adaxially glabrous, abaxially sparsely covered with lanceolate and light brown microscales; frond texture thinly papery; venation pinnate, visible abaxially, indistinct adaxially; lateral veins reaching tips of teeth, dichotomous or simple above midrib, often simple below midrib; clavate and unusually swollen at ends (hydathodes). Sori small, terminal on shorter veinlets, medial or slightly closer to pinna margin, 1-6 above midrib, 0-2 below midrib, lower part of lamina often sterile; indusia present, brown, erose, evanescent.

● Acidic soils of wet sandstone cliffs in valleys, roadsides, by streams; 400-500 m. W Hubei (Lichuan), NW Hunan (Sangzhi).

Polystichum wulingshanense is similar to P. ichangense in having hydathodes at vein ends, though slightly indistinct; it differs by its rounded pinna apex, thinner and mostly deflexed pinnae, and location in acidic soils.