南川耳蕨 nan chuan er jue

Plants evergreen. Rhizome erect, short, together with stipe base 1-2 cm in diam., upper part densely scaly; scales brown, broadly lanceolate, membranous. Fronds few, 14-19 cm; stipe light stramineous, 4-5 cm, ca. 1 mm in diam.; stipe scales rufous, broadly lanceolate, toothed, acuminate. Lamina 1-pinnate, light green when dry, adaxially darker, lanceolate, 10-14 × 2-2.7 cm, slightly contracted downward, acuminate; rachis light stramineous, without proliferous bulbils, sparsely scaly; scales brown, lanceolate or linear, sparsely toothed. Pinnae 14-18 pairs, alternate, lower pairs contiguous, upper pairs remote, shortly stalked, attached at nearly right angles with rachis but lower pairs angled basiscopically, rhomboid-oblong, basal pairs 0.7-1 cm, middle pairs 1-1.3 cm wide, apices obtuse but with a spinule and slightly curved acroscopically, bases asymmetrical, acroscopic base auriculate, auricles semicircular or almost triangular with ca. 3 small obtuse low teeth, proximal margins of auricles slightly curved and slightly overlapping with rachis, distal part of acroscopic margins toothed, teeth 4 or 5, obtuse or weakly spinulose, basal basiscopic margins cuneate, truncate, margins entire, distal basiscopic margins curved upward and with 4 obtuse weakly spinulose teeth; adaxially glabrous, abaxially sparsely covered with light brown linear microscales; frond texture papery; venation visible or distinct abaxially, indistinct adaxially, pinnate; lateral veins nearly reaching pinna margin, pinnate from base upward above midrib, dichotomous or simple, simple or dichotomous below midrib. Sori terminal on shorter veinlets, close to pinna margin, up to 7 above midrib, 2-4 below middle midrib; indusia present, grayish brown, erose, evanescent.

● Wet limestone crevices; ca. 1200 m. Chongqing (Jinfo Shan).

Polystichum nanchurnicum was not treated in FRPS. Its relationship with P. deltodon is unclear.