线裂铁角蕨 xian lie tie jiao jue

Asplenium bodinieri Christ; A. fuscipes Baker; A. subtoramanum Ching ex S. H. Wu; A. toramanum Makino.

Plants 12-35 cm tall. Rhizome erect, short, apex scaly; scales dark brown to black, narrowly triangular to linear-subulate, margin fimbriate to subentire. Fronds caespitose; stipe shiny, purplish black, 6-15(-18) cm, terete, rigid and threadlike, with brown, multicellular uniseriate hairs or subglabrous; lamina triangular, 7-12 × 5-10 cm, base truncate, bipinnate to tripinnate-pinnatifid, apex acuminate to caudate; pinnae 10-15 pairs, subopposite to alternate, lower pinnae stalked, upper almost sessile, stalk dark brown abaxially, basal 1 or 2 pinnae longest and often falcate, narrowly triangular to oblong, 2.5-7 × 1.5-2 cm, base asymmetrical, on acroscopic side auriculate-truncate, basiscopic side cuneate, up to bipinnate-pinnatifid, apex obtuse; pinnules 6-8 pairs, anadromous, usually sessile but shortly stalked in more divided fronds, basal acroscopic pinnule largest, ovate, 7-9 × 4-7 mm, base asymmetrical, acroscopic side truncate, basiscopic cuneate, apex obtuse to truncate; ultimate segments ovate-oblong to linear, apex with 2-4 short and broadly triangular, obtuse to submucronate or sharp teeth. Costa sulcate adaxially, green, veins often raised adaxially when dry, anadromously branching, (1 or)2-6 veins per ultimate segment, terminal hydathode obvious, and not reaching margin. Frond firmly herbaceous, green, lamina with multicellular uniseriate hairs or subglabrous; rachis shiny purplish black, becoming green in upper half toward apex, with brown, multicellular uniseriate hairs or subglabrous, sulcate adaxially. Sori (1 or)2-4 per pinnule or segment, medial to subterminal on acroscopic veinlets, confluent at maturity, oval to linear, 1-2 mm; indusia grayish green, oval to linear, membranous, repand to entire, opening toward costa or costule, persistent. Spores brown to dark brown, lophate (cristate-alate) perispore. Plants tetraploid: 2n = 144.

On limestone rocks, on buildings and walls; 300-1700 m. Fujian, Guangdong, Guizhou, Hunan, Sichuan, Yunnan [Japan, Vietnam].

Asplenium coenobiale has a variable frond division probably depending on growing conditions with large and more divided plants often growing on rocks in forests. Plants are tetraploid but often produce some aborted spores. Further study will have to show whether they are sexual or agamosporous. In Chinese literature, this name has often been misapplied to the next species (A. pulcherrimum). Due to this confusion, its distribution is not well known.