剑叶叉蕨 jian ye cha jue

Nephrodium leptophyllum C. H. Wright, Bull. Misc. Inform. Kew 1906: 11. 1906; Aspidium leptophyllum (C. H. Wright) C. Christensen.

Plants terrestrial, 25-40 m tall. Rhizome erect, short, ca. 1 cm in diam., scaly at apex and stipe bases; scales brown, linear-lanceolate, 3-4 mm, entire, membranous, acuminate. Fronds clustered; stipe stramineous to light brown, 2-5 cm, ca. 2 mm in diam., grooved, broadly winged nearly to base, sparsely scaly toward apex. Lamina simple, dimorphic; sterile fronds broad, fertile fronds homomorphic but taller and narrowed, 35-40 × 3-4 cm, papery, deep green when dried; main veins and lateral veins stramineous, glabrous on both sides. Veinlets forming inconspicuous subhexagonal areoles, included veinlets forked. Sori orbicular, terminal on included veinlets, in 3-5 irregular rows between lateral veins; indusia brown, orbicular, membranous, entire, persistent or revolute.

Forests; 300-400 m. Yunnan [N Vietnam].