Pteris – the most diverse ferns

Pteris L. (Pteridaceae) is a cosmopolitan fern genus growing either terrestrially or lithophytically (on rocks) in forests, coastal areas and xeric niches. Most species of this genus occur in tropical and subtropical areas, but a few live in temperate regions. Species of Pteris are usually distributed at lower altitudes, below 2500 m, but Pteris coriacea Desv. can be found up to 3500 m. Some species have ornamental value, especially those with pale marks on the leaves. A few species are cultivated worldwide and some have become naturalized. With 250–300 species, Pteris is one of the most diverse fern genera. The uncertainty about the total number of species highlights the need for further taxonomic and phylogenetic studies.

A recent article in Annals of Botany finds that the biogeographic history of Pteris highlights long-distance dispersal as a major process shaping the worldwide distribution of the genus. Colonizing into different niches was followed by subsequent morphological diversification, and dispersal events followed by allopatric and parapatric speciation have contributed to the species diversity. This phylogeny should contribute to a new, more reliable infrageneric classification, based not just on a few morphological characters but also on ecological traits and geographic distribution.

Chao, Y.S., Rouhan, G., Amoroso, V.B., and Chiou, W. L. (2014) Molecular phylogeny and biogeography of the fern genus Pteris (Pteridaceae). Annals of Botany, 114(1): 109-124.