A taxonomic revision on Aleuritopteris argentea (Gmél.) Fée

The fern genus Aleuritopteris Fée is characterized by small habit with an indument of farina on the leaves, and is adapted to xeric environments. Aleuritopteris argentea (Gmél.) Fée, which is distributed across China, has been one of the most problematic fern species with respect to its generic definition. In this paper, the taxonomy of this species is revised based on examination of its herbaria specimens, field work, and observation of spore morphology. A. argentea var. obscura (Christ) Ching is reinstated while A. shensiensis Ching is submerged to this variety. Meanwhile, A. subargentea Ching, A. argentea (Gmél.) Fée var. geraniifolia Ching et S. K. Wu and A. argentea (Gmél.) Fée var. flava Ching et S. K. Wu are reduced to A. argentea var. argentea.