五裂叉蕨 wu lie cha jue

Nephrodium quinquefidum Baker, J. Bot. 28: 265. 1890; Aspidium esquirolii (Christ) C. Christensen; A. polysorum Rosenstock; A. quinquefidum (Baker) Diels; Sagenia esquirolii Christ; Tectaria hekouensis Ching & Chu H. Wang.

Plants terrestrial, 60-80 cm tall. Rhizome erect, short, stout, 1-2 cm in diam., scaly at apex and stipe bases; scales dark brown, lanceolate, 5-7 mm, membranous, entire, apices long acuminate. Fronds clustered; stipe deep stramineous to brown or reddish, 25-40 cm, 3-4 mm in diam., grooved, sparsely hairy. Laminae subdimorphic, fertile fronds rather tall and slightly narrowed, odd-pinnate, brown when dried, deltoid-ovate, 20-35 × 18-30 cm, herbaceous, both surfaces glabrous; rachises and costae light brown, glabrous adaxially, pubescent and raised abaxially; terminal pinna simple or 3-lobed; middle lobes broadly lanceolate, 16-22 × 4-8 cm, bases narrowed, slightly cordulate, apices acuminate to caudate, margins undulate to dentate, stalk ca. 1.5 cm, lateral lobes falcate-lanceolate, rather small; lateral pinnae of a single pair, opposite, subsessile, ovate-lanceolate, 14-15 × 4-5 cm, slightly oblique, subentire to undulate, bases asymmetrical and cuneate, apices acuminate; gemmae present, axillary. Veinlets forming subhexagonal areoles, inconspicuous adaxially, raised and pubescent abaxially, included veinlets forked. Sori orbicular, on anastomosing veins, in irregular rows between lateral veins; indusia dark brown, reniform, membranous, entire, caducous.

Dense forests; 300-600 m. Guangxi, Guizhou, Yunnan [N Vietnam].

From Yunnan (Hekou), a form of Tectaria quinquefida is known without gemmae and glabrescent pinna rachises, which was described as T. hekouensis. These characters are a regional form that may be recognizable at the variety level.