石韦 shi wei

Acrostichum lingua Thunberg in Murray, Syst. Veg., ed. 14, 928. 1784; Cyclophorus bodinieri H. Léveillé; C. lingua (Thunberg) Desvaux; C. lingua var. angustifrons Hayata; C. lingua var. attenuata Rosenstock; C. martinii (Christ) C. Christensen; C. taiwanensis (Christ) C. Christensen; Niphobolus lingua Sprengel; N. martinii Christ; Polycampium lingua (Thunberg) C. Presl; Polypodium lingua (Thunberg) Swartz; P. taiwanense Christ; Pyrrosia caudifrons Ching, Boufford & Shing; P. martinii (Christ) Ching; P. medogensis Ching & S. K. Wu.

Plants 10-30 cm tall. Rhizome long creeping, 1.2-3.7 mm in diam., in cross section sometimes with a single, central sclerenchyma strand; phyllopodia (0.5-)2-8 cm apart, lateral buds alternating with phyllopodia. Scales peltate, (2.2-)4-9.5 × 0.7-1.6 mm, base entire to irregularly dentate; acumen shiny light brown, with long, curly marginal cilia; short, ± ovate scales occasionally present. Fronds subdimorphic, stipitate. Sterile fronds: stipe 1-30 cm, lamina (5-)10-20 × 1.5-7 cm, base ± gradually attenuate, apex shortly acuminate to long caudate. Fertile fronds: stipe 1.5-25 cm; lamina widest at or below middle, 5.5-22 × 0.8-3 cm. Hydathodes distinct, ± superficial, rarely distinctly sunken. Indument persistent, monomorphic, thin, light to grayish brown; hairs 0.3-0.5 mm in diam., with appressed, boat-shaped rays. Sori superficial, without central bundle of paraphyses. Sporangia with stalks 0.75-1 × as long as capsule.

On tree trunks in forests or on rather dry rocks; 100-1900 m. Anhui, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hainan, Hunan, Jiangsu, Jiangxi, Liaoning, Sichuan, Taiwan, Yunnan, Zhejiang [India, Japan, Korea, Myanmar, Vietnam].

The whole plant is used in traditional Chinese medicine.

Pyrrosia caudifrons was based on a number of specimens showing an extreme within a continuous variation from P. lingua. No character distinguishes them other than a lamina apex that is slightly more protracted than is usual in P. lingua.