Cyclosorus is a genus of ferns in the family Thelypteridaceae, subfamily Thelypteridoideae, in the Pteridophyte Phylogeny Group classification of 2016 (PPG I).[1] Other sources sink Cyclosorus into a very broadly defined genus Thelypteris,[2] 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.[3][1]
There are also fossil species known from the Eocene of South China[4] and the Quaternary of Australia.
The genus is named from the Greek, referring to the circular sori.[5]
Species
As of January 2020[update], the Checklist of Ferns and Lycophytes of the World accepted the following extant species, although noting that only two to four probably belonged in the genus sensu stricto, the rest needing in future to be distributed among other genera.[6]
^ abPPG I (2016). "A community-derived classification for extant lycophytes and ferns". Journal of Systematics and Evolution. 54 (6): 563–603. doi:10.1111/jse.12229. S2CID39980610.
^"Cyclosorus Link", Plants of the World Online, Royal Botanic Gardens, Kew, retrieved 2020-01-16
^Lin, Youxing; Li, Zhongyang & Iwatsuki, Kunio, "Cyclosorus", in Wu, Zhengyi; Raven, Peter H. & Hong, Deyuan (eds.), Flora of China (online), eFloras.org, retrieved 2020-01-16
^A new find of the fossil Cyclosorus from the Eocene of South China and its paleoclimatic implication. Serge V. Naugolnykh, Li Wang, Meng Han and Jian-Hua Jin; 2016, Journal of Plant Research. 129 (1), pages 3–12, doi:10.1007/s10265-015-0765-0
^Les Robinson - Field Guide to the Native Plants of Sydney, ISBN978-0-7318-1211-0 page 320
