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The diverse and pantropical genus Ctenitis, in the Dryopteridaceae, has been largely ignored in phylogenetic studies until now. In this study, we fill in this gap by reconstructing the first comprehensive phylogeny of the genus including 53 species currently recognized in the genus Ctenitis, among which seven species formerly were assigned to the genus Pseudotectaria and one to Heterogonium. Special emphasis was given to the sampling of species occurring in the African-Indian Ocean region. The presented results include reconstruction of a biogeographic scenario based on estimated divergence times and ancestral area reconstruction. Our findings confirm the inclusion, within Ctenitis, of the Indian Ocean species formerly placed in Pseudotectaria and Heterogonium. The crown group divergence was estimated to date back to the Oligocene or Early Miocene. The biogeographical scenario indicates an initial divergence of the Asian-Pacific ranges and the neotropical ranges, and a subsequent colonization of the Afro-Madagascan region by a lineage with neotropical ancestors. The Afro-Madagascan lineage splits into a lineage endemic to the Mascarene islands and a lineage occurring in Madagascar, the Comoros and Africa. The range expansion towards Africa and Madagascar was estimated to date back to the late Miocene, whereas the estimated ages for the onset of the diversification of the Mascarene diversity is consistent with the ages of these young, volcanic islands. The absence of any extant species of Ctenitis with a multi-continental distribution range and the rarity of inter-island dispersal and speciation in the Indian Ocean region suggest a limited contribution of long distance dispersal to the biogeographical history of this fern genus, versus a high contribution of local speciation., (Copyright © 2017. Published by Elsevier Inc.)

A taxonomic revision of Ctenitis (C. Chr.) C. Chr. (Dryopteridaceae) from Africa and the Western Indian Ocean was carried out. Forty species are recognized, of which 12 are described as new, eight are transferred to Ctenitis from other genera, and one is elevated from variety to species and transferred from Aspidium Sw. to Ctenitis. These 21 nomenclatural novelties include C. analamazaotrensis (Rakotondr.) Hennequin & Rouhan (comb. nov.), C. brevipetiolulata Li Bing Zhang & Yi F. Duan (sp. nov.), C. bullescens Rouhan, Li Bing Zhang & Yi F. Duan (sp. nov.), C. cerea Li Bing Zhang & Yi F. Duan (sp. nov.), C. comorensis Li Bing Zhang & Yi F. Duan (sp. nov.), C. crinigera (C. Chr.) Hennequin & Rouhan (comb. nov.), C. decaryana (C. Chr.) Hennequin & Rouhan (comb. nov.), C. dentata Li Bing Zhang & Yi F. Duan (sp. nov.), C. fibrillosa (Baker) Li Bing Zhang & Yi F. Duan (comb. nov.), C. hispida (Kuhn) Li Bing Zhang & Yi F. Duan (comb. & stat. nov.), C. jouyana (Rakotondr.) Hennequin & Rouhan (comb. nov.), C. longivillosa Li Bing Zhang & Yi F. Duan (sp. nov.), C. marginalisora Li Bing Zhang & Yi F. Duan (sp. nov.), C. mayottensis Li Bing Zhang & Yi F. Duan (sp. nov.), C. multilobata Li Bing Zhang, Yi F. Duan & Rouhan (sp. nov.), C. reunionensis Hennequin, Li Bing Zhang & Yi F. Duan (sp. nov.), C. sieberiana (Kaulf.) Hennequin & Rouhan (comb. nov.), C. sparsa Li Bing Zhang & Yi F. Duan (sp. nov.), C. spekei (Baker) Li Bing Zhang & Yi F. Duan (comb. nov.), C. subcrenulata (Baker) Li Bing Zhang, Rouhan & Yi F. Duan (comb. nov.), and C. tardieu-blotiae Li Bing Zhang & Yi F. Duan (sp. nov.). A key to these species is provided; all species are described and illustrated; and information on their distribution and habitats is given. Twenty-three relevant species reported in the literature are excluded from the flora, and their taxonomy, distribution, and nomenclature are discussed. Seventeen related names are lectotypified or neotypified including Aspidium cirrhosum Schumach., A. crinitum (Poir.) Wall. var. hispida Kuhn, A. cyclochlamys Fée, A. nitidum Bory ex Willd., A. pauciflorum Kaulf., A. sulcatum Kaulf. ex Bory, C. anjenabensis Tardieu, Dryopteris blepharochlamys C. Chr., Gymnogramma subsimilis Hook., Nephrodium crinitum (Poir.) Desv. var. maritimum Cordem., N. magnum Baker, N. spekei Baker, N. welwitschii Baker, Phegopteris biformis Mett. ex Kuhn, P. bivestita Mett., Polypodium baronii Baker, and P. efulense Baker; type information of related 262 names is also given. [ABSTRACT FROM AUTHOR]

Tectaria (Tectariaceae) is one of the most confusing fern genera in terms of its circumscription and phylogeny. Since its original description, a number of genera had been moved into or related with this genus, while others had been segregated from it. Tectaria is also among the largest fern genera, comprising 150–210 mostly tropical species. Previous molecular studies have been far from comprehensive (sampling no more than 76 accessions from 52 species), limited in geographic scope (mainly restricted to Asia), and based exclusively on plastid markers. In the present study, DNA sequences of eight plastid and one nuclear marker of 360 accessions representing ca. 130 species of Tectaria , ca. 36 species of six non- Tectaria genera in Tectariaceae, 12 species of Davalliaceae, Oleandraceae, and Polypodiaceae, and 13 species of Lomariopsidaceae were used to infer a phylogeny with maximum likelihood, Bayesian inference, and maximum parsimony approaches. Our major results include: (1) the most recently proposed circumscription of Tectaria is strongly supported as monophyletic; (2) the genera Lenda , Microbrochis , Phlebiogonium , and Sagenia , sampled here for the first time, are resolved as part of Tectaria ; (3) four superclades representing early splits in Tectaria are identified, with the Old World species being sister to the New World species; (4) 12 well-supported major clades in Tectaria are revealed, differing from one another in molecular, morphological, and geographical features; (5) evolution of 13 morphological characters is inferred in a phylogenetic context and morphological synapomorphies of various clades are identified; and in particular (6) free venation in Tectaria is inferred to be repeatedly derived from anastomosing venation, an evolutionary phenomenon not documented previously in vascular plants in a phylogenetic context based on both plastid and nuclear evidence. [ABSTRACT FROM AUTHOR]