Lepisorus longifolius Ching (1959), not (Blume) Holttum (1955); L. longus Ching.

Plants 67-70 cm tall. Rhizomes long and creeping, 2-4 mm in diam., densely scaly at tip; scales brownish, ovate-lanceolate, 2.5-4 × 1-1.5 mm, basifixed, base broadly rounded, margin entire, apex acuminate; lumina isodiametric, brownish, transparent. Fronds 0.5-2 cm apart; stipe straw-colored to deep brown, 2-15 cm, 1.5-2 mm in diam., hard and smooth; base with 3 vascular bundles arranged in a triangle; lamina deep brown or gray-green on both surfaces when dried, lanceolate or linear-lanceolate, 20-65 × 1-3.2 cm, widest at or below middle, leathery or sometimes soft leathery, scales orbicular or lanceolate, lumina brown, base narrowly cuneate and decurrent, margin entire, apex obtuse or acuminate; costa raised on both sides, veinlets obscure. Sori closer to margin, orbicular or elliptic, 3-4 mm in diam.; paraphyses 0.35-0.5 mm in diam.

Lepisorus longus was distinguished from L. affinis by its narrow fronds. The widths of fronds are variable even on one rhizome, and the rhizome scales, epidermis, and spore ornamentation show very little difference; thus, L. longus is treated as a synonym of L. affinis.

● On tree trunks in forests; 900-1700 m. Hainan (Qiongzhong).