狭鳞双盖蕨 xia lin shuang gai jue

Rhizome erect, black, robust, woody, stiff, apex with dense scales; scales black, linear, 3-8 mm, thickly membranous, margin thin, dentate; fronds caespitose. Fertile frond ca. 1 m; stipe black at base, upward stramineous or pale brown-stramineous, 24-55 cm, ca. 4 mm in diam. at base, base with sparse narrowly lanceolate scales, upward glabrous; rachis stramineous, glabrous; lamina 1-imparipinnate, elliptic, 40-45 × 19-25 cm; pinnae 4 or 5 pairs, equal in size, oblique, stalked (stalk 4-8 mm), lanceolate, 20-25 × 4-4.5 cm, gradually narrowed, acuminate at apex, base cuneate, margin entire or dentate near apex, often incurved when dry; costae raised, rounded abaxially, shallowly grooved adaxially; veinlets prominent abaxially, visible adaxially, oblique or slightly oblique, 3 or 4 per veinlet group, straight, parallel, reaching margin of lamina. Lamina subleathery, dark green or brown-green when dry. Sori and indusia linear, 2 or 3 per veinlet group, brown, longest, double on acroscopic veinlet, basal sori long and close to costa, distal sori shorter.

Dense forests, beside streamlets; ca. 1000 m. S Guangxi, Hainan [N Vietnam].

Diplazium stenolepis is similar to D. hainanense but differs by the pinnae lanceolate, scales linear, and upper part of stipe and rachis glabrous.