Cyclosorus

Cyclosorus is a genus of ferns in the family Thelypteridaceae, subfamily Thelypteridoideae, in the Pteridophyte Phylogeny Group classification of 2016 (PPG I). Other sources sink Cyclosorus into a very broadly defined genus Thelypteris, or expand the genus to include other genera which PPG I keeps separate. Thus the online Flora of China suggests there are about 250 species compared to the two species suggested in PPG I.

There are also fossil species known from the Eocene of South China and the Quaternary of Australia.

The genus is named from the Greek, referring to the circular sori.