Description from Flora of China
Polypodium assimile Baker, J. Bot. 13: 201. 1875; Cyclophorus assimilis (Baker) C. Christensen; C. assimilis f. lobata C. Christensen; C. assimilis var. mollifrons Handel-Mazzetti; Niphobolus assimilis (Baker) Diels; Pyrrosia assimilis f. lobata (C. Christensen) Ching; P. assimilis var. longissima Ching; P. dimorpha X. H. Guo & S. B. Zhou (2005), not (Copeland) Parris (1980).
Plants 5-15(-20) cm tall. Rhizome shortly elongated, not grooved ventrally, (0.5-)1.8-2.2 mm in diam., in cross section with 10-20 or sometimes more scattered sclerenchyma strands; phyllopodia 0.2-0.5 cm apart, lateral buds alternating with phyllopodia. Scales peltate, 1.6-5.8 × 0.7-1.1 mm, base entire to denticulate; acumen dull brown to blackish with a lighter margin, dentate. Fronds monomorphic, sessile, linear, 6-20 × 0.2-1 cm. Hydathodes distinct, sunken. Indument monomorphic, sparse; hairs 0.5-1.8 mm in diam., with erect-spreading, acicular rays of very unequal length. Sori superficial, without central bundle of paraphyses. Sporangia with stalks up to 1 × as long as capsule.
The apparent earlier homonym "Polypodium assimile Kunze" (Linnaea 23: 275. 1850) is a nomen nudum and was not therefore validly published (Melbourne Code, Art. 38.1(a)). Pyrrosia dimorpha (2005) was based on material from Anhui with most fronds dichotomously once or more divided, mostly near the apex.
● On shaded wet rocks in forests on slopes; 200-1000 m. Anhui, Fujian, Guangdong, Guangxi, Guizhou, Henan, Hunan, Jiangxi, Sichuan, Xinjiang, Yunnan, Zhejiang.