13. Asplenium oblanceolatum Copeland, Philipp. J. Sci., C. 9: 229. 1914.
黑鳞巢蕨 hei lin chao jue
Asplenium latibasis (Ching) Viane (1991), not (Ching & Shing) Nakaike (1986); A. phyllitidis D. Don subsp. malesicum Holttum; A. subantiquum (Ching ex S. H. Wu) Viane; Neottopteris latibasis Ching; N. subantiqua Ching ex S. H. Wu.
Plants 60-100 cm tall. Rhizome erect, dark brown, short and thick, woody, apex scaly; scales brown to dark brown, narrowly triangular, membranous, apex acuminate, fimbriate. Fronds caespitose; stipe dark brown, very short, 1-2 cm, when dry semiterete on both sides, base with scales similar to those on rhizome; lamina lanceolate to narrowly lanceolate, 50-60 (-100) × (4-)8-9(-12) cm, gradually decurrent toward stipe, margin entire, with a cartilaginous narrow edge or slightly recurved when dry, apex acute. Midrib prominent on both sides, semiterete to obtusely carinate abaxially, grooved adaxially when dry, dark brown or grayish brown, glabrous; veinlets visible, forked or simple, parallel, at their apex united to marginal vein. Fronds firmly papery to subleathery, green but brownish when dry, glabrous. Sori linear, 2-3 cm, on acroscopic veinlets, running from near their base up to (1/2-)2/3-3/4 of their length, lower part of lamina usually sterile; indusia brown to dark brown, linear, thickly membranous, entire, persistent. Spores with echinate perispore. Plants tetraploid: 2n = 144.
On tree trunks in dense forests; 100-1100 m. Hainan, SE Yunnan [India, Malaysia, Myanmar, Thailand, Vietnam].
Asplenium oblanceolatum is similar to other members of the A. nidus complex but differs from all by its echinate perispores (Holttum, Gard. Bull. Singapore 27: 143-154. 1974; Y. L. Zhang et al., Sporae Pterid. Sin. 240-263. 1976; Wei & Dong, Nordic J. Bot. 30: 90-103. 2012). In addition, it differs from small A. nidus by its midrib structure and from A. phyllitidis and A. antiquum by its narrower scales.
We were unable to locate and study the type of Asplenium anguineum Christ (J. Bot. (Morot), ser. 2, 1: 265. 1908) from Vietnam; if this has echinate spores, it would be the oldest name for A. oblanceolatum/A. phyllitidis subsp. malesicum.