Ferns & Horsetails

Plant phylogeny has changed a lot since the advent of molecular systematics and in an effort to standardise the classification of ferns and their allies, the Pteridophyte Phylogeny Group (PPG) published their first phylogeny of the group in 2016. In this classification the class Polypodiopsida encompasses four subclasses: Equisetidae (Horsetails; approx. 20 species); Ophioglossidae (Whisk Ferns; 92 species); Marattiidae (approx. 130 species) and the Polypodiidae (ferns; approx. 10,000 species).