LYCOPHYES AND MONILOPHYTES (FERNS)

Abstract

There have been significant changes (updates) in classification and grouping of ferns and their phylogenies in recent years. Fern classifications have historically been subjected to controversies. With the new molecular phylogeny, much of the familiar terminology of higher groupings applied to ferns has been replaced as well. It may appear as an error by anyone familiar with earlier classifications when Equisitaceae and Ophioglossacace are actually included with the common familiar ferns. As noted in the introductory remarks in this book, horticulture, if interpreted as practical botany, has remained far behind in understanding fern classifications. Although there have also been numerous changes in gymnosperms and angiosperms, none has been as sweeping as that of ferns. The most recent treatment of ferns is that of Chritenhusz et al. (2017). Regretfully, its complex organization, arrangement, and recognition of many new taxa are far above and beyond the scope of this book, which is primarily intended as a practical teaching and learning tool. The somewhat unfamiliar treatments that follow are primarily based on APG IV (2016–2021), the most important source of plant classifications based on DNA phylogeny (the evolutionary history of organisms). Thus, for all intents and purposes, taxonomy of ferns remains unsettled. The following is primarily based on Judd et al. (2015).