中华水龙骨 zhong hua shui long gu

Polypodium subamoenum C. B. Clarke var. chinense Christ, Nuovo Giorn. Bot. Ital., n.s., 4: 99. 1897; Goniophlebium amoenum J. Smith var. chinense (Christ) Rödl-Linder; G. chinense (Christ) X. C. Zhang; P. amoenum Wallich ex Mettenius var. chinense (Christ) Ching; P. amoenum var. tongolense C. B. Clarke ["tonglense"]; P. amoenum var. xerophyticum Mehra & Bir.

Rhizome long creeping, 2-3 mm in diam., densely covered with scales; scales black, ovate-lanceolate, margin sparsely toothed, apex acuminate. Fronds remote. Stipe straw-colored, 10-20 cm, glabrous. Lamina pinnatipartite or pinnatisect at lower portion, ovate-lanceolate or broadly lanceolate in outline, 15-25 × 7-10 cm, base cordate, apex caudate. Segments 15-25 pairs, linear-lanceolate, 3-5 cm × 5-7 mm, margin serrate, apex acuminate; basal pairs slightly shorter and deflexed. Veins reticulate, costa visible, straw-colored, veinlets invisible. Lamina herbaceous, subglabrous on both surfaces, scaly abaxially. Sori small, orbicular, terminal on included veinlets, close to costa.

● Epiphytic on rocks or on tree trunks; 900-2800 m. Anhui, Gansu, Guangdong, Guizhou, Hebei, Henan, Hubei, Jiangxi, Shaanxi, Shanxi, Sichuan, Taiwan, Yunnan, Zhejiang.

While Rödl-Linder (Blumea 34(2): 391. 1990) treated material of this species (Polypodiodes chinensis) as a hairy variety of the following species (P. amoena), Fraser-Jenkins (Taxon. Revis. Indian Subcontinental Pteridophytes, 43. 2008) suggested that it merely represents more hairy populations of P. amoena not worthy of formal recognition; he also indicated that he regards Polypodium yunnanense Franchet as part of this taxon if recognized as a distinct species and thus providing the oldest species epithet. However, the concept used here is based on a different set of characters from those discussed by Fraser-Jenkins. The names Polypodium pseudo-amoenum Ching and Polypodiodes pseudo-amoenum (Ching) Ching have been applied to this taxon but have never been validated. The former was first mentioned as a synonym in the protologue of Polypodium amoenum var. chinense (Christ) Ching. The name Polypodium pseudo-amoenum var. pilosum Ching is also invalid (Melbourne Code, Art. 35.1).