下延石韦 xia yan shi wei

Niphobolus costatus Wallich ex C. Presl, Tent. Pterid. 202. 1836; Apalophlebia costata (Wallich ex C. Presl) C. Presl; Cyclophorus beddomeanus (Giesenhagen) C. Christensen, nom. illeg. superfl.; Niphobolus beddomeanus Giesenhagen, nom. illeg. superfl.; N. beddomeanus f. fallax Giesenhagen; Polypodium costatum Hooker (1863), not Kunze (1834), nor Mettenius (1857); Pyrrosia beddomeana (Giesenhagen) Ching, nom. illeg. superfl.

Plants 20-50 cm tall. Rhizome short, up to 5 mm in diam., in cross section without sclerenchyma strands; phyllopodia close together, lateral buds basal on phyllopodia. Scales basifixed, 8-10 mm, basal margin often with glands on long teeth; acumen entire, shiny, brown. Fronds monomorphic, substipitate or estipitate; stipe 1-5 cm; lamina widest at middle, 23-50 × 2.5-6 cm, base very gradually narrowed, apex acuminate. Hydathodes distinct, ± superficial. Indument persistent, dense, grayish brown; dimorphic; upper layer composed of hairs 0.4-1.9 mm in diam., with appressed, narrowly boat-shaped rays, lower layer with mainly woolly rays. Sori superficial, without central bundle of paraphyses. Sporangia sessile or on short stalks to 0.25 × as long as capsule.

On tree trunks or rocks in forests; 300-2000 m. Xizang, Yunnan [Bhutan, India, Myanmar, Nepal, Thailand, Vietnam].

Chinese representatives of this species have been erroneously identified as Pyrrosia stigmosa (Y. C. Wu et al., Bull. Dept. Biol. Sun Yatsen Univ. 3: 340, t. 161. 1932; Ching & Wu, Fl. Xizang. 1: 327. 1983) and as P. princeps (Mettenius) C. V. Morton (Shing & Iwatsuki, J. Jap. Bot. 72: 76. 1997).