Classification of Lycophytes and Ferns of Ethiopia and Eritrea, According to the Pteridophyte Phylogeny Group (PPG) – I

Abstract

Aims: To conduct an in-depth inventory of the pteridophytes of Ethiopia and Eritrea, classifying them based on the Pteridophyte Phylogeny Group I (PPG I), in order to conform to the new trends in pteridophyte classification. Study Design: The desktop research approach. Place and Duration of Study: Data for this study was collected from the National Herbarium of Ethiopia in Addis Abeba (ETH) and other literature [1]. The study was carried out from February 2023 to June 2024. Methodology: The desktop research approach was applied in this study. Secondary data on species of pteridophytes of Ethiopia and Eritrea was obtained through a compilation published in 2009 by groups of researchers from the National Herbarium (ETH) of the University of Addis Ababa and Uppsala University of Sweden through the Department of Systematic Biology. It was published in Volume I of the ‘Flora of Ethiopia and Eritrea’ (based solely on morphological characterization). Other literature were consulted for new species [2,1]. Classification of species were adjusted to conform to PPG-I classification system (a modern, comprehensive classification, community-based approach which uses monophyly as the primary criterion for the recognition of taxa. Results: This study has produced a comprehensive checklist of documented species of pteridophytes in Ethiopia and Eritrea according to PPG-I. It is comprised of 2 classes, 14 orders, 27 families, 76 genera and 193 species. Conclusion: This study has revised the classification of pteridophytes of Ethiopia and Eritrea to conform to the PPG I classification approach. This resulted in 27 families, 76 genera and 192 species, with changes recorded at all levels of classification except the number of species. This outcome is therefore suggested to be applied in the herbaria and adopted by researchers of pteridophytes in Ethiopia and Eritrea, for ease of communication internationally.