尖羽角蕨 jian yu jiao jue

Diplazium christensenianum Koidzumi, Bot. Mag. (Tokyo) 38: 105. 1924; Athyrium crenulatoserrulatum Makino f. hakonense Makino; A. hakonense (Makino) C. Christensen; Cornopteris hakonensis (Makino) Nakai.

Plants summer-green. Rhizome creeping, apex with muddy-brown, entire, elliptic-lanceolate scales; fronds approximate. Fertile frond up to 90 cm; stipe pale green, slightly purple-red, up to 45 cm, scaly throughout with brown, entire lanceolate scales; lamina 2-pinnate below apex, deltoid-ovate, up to 45(-60) × 30(-45) cm, apex acuminate; pinnae up to 10 pairs, ascending; lower pinnae opposite or nearly so, elliptic-lanceolate, base truncate, apex acuminate; basal pinnae shortly stalked, other pinnae sessile; middle pinnae largest, up to 20 × 7 cm; pinnules up to 12 pairs, alternate, subspreading, sessile, lanceolate or ovate-lanceolate, middle pinnules up to 4 × 1.5 cm, base broadly cuneate, pinnatifid to pinnatisect, apex acuminate, shortly acuminate, or subrounded; pinnule lobes up to 10 pairs, subrectangular, ascending, slightly falcate, serrate or subentire, truncate or obtuse at apex; veins pinnate, veinlets 3-5 pairs, simple, ending inframarginally. Lamina thinly herbaceous, brown-green when dry, rachis, costae, and midribs abaxially with pale brown lanceolate entire scales and unicellular short hairs, rarely also 2- or 3-celled short nodose hairs. Sori narrowly elliptic, medial.

Forest wetlands beside cliffs; ca. 800 m. Zhejiang [Japan, S Korea].