Polystichum weimingii sp nov (sect. Metapolystichum, Dryopteridaceae) from Southern Yunnan, China

A new fern species, Polystichum weimingii (sect. Metapolystichum, Dryopteridaceae), is described from Southern Yunnan, China. The new species is morphologically most similar to R discretum. Compared to P. discretion, P weimingii has a smaller habit, lanate (linear and curly), brown rachis scales, and pinnules without obvious aristate spines on the margin. In contrast, P. discretum is larger, has linear, dark brown rachis scales, and has pinnules with obvious aristate spines on the margin. The new species also differs from P discretum in spore morphology. Features of the new species in anatomy of lamina epidermis, spore morphology, geographical distribution, and ecology are given. The relationships with three other closely related species in Polystichum ser. Linearia are discussed