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We conducted phylogenetic analyses of the fern family Grammitidaceae using sequences from two cpDNA genes and from morphological characters. Data were obtained for 73 species from most recognized genera in the family. The genera Adenophorus, Ceradenia, Calymmodon, Cochlidium, Enterosora, and Melpomene were each strongly supported as being monophyletic. Other recognized genera that were not supported as monophyletic included Ctenopteris, Grammitis, Lellingeria, Micropolypodium, Prosaptia, and Terpsichore. Several previously unrecognized clades were identified, some of which are characterized by distinctive morphological features. Analyses of the distribution of morphological character states on our inferred phylogeny showed extremely high levels of homoplastic evolution for many different characters. Homoplasy for morphological characters was considerably greater than for molecular characters. Many of the characters that exhibited high levels of convergent or parallel evolution across the phylogeny are features that have been commonly used to circumscribe genera in this group (e.g., leaf blade dissection, various rhizome scale characters, and glandular paraphyses). Conversely, some of the characters that exhibited relatively low levels of homoplasy have either not been regarded as having taxonomic value or have been ignored (e.g., root insertion, rhizome scale sheen). Our data support a New World origin of Grammitidaceae, with Old World taxa generally being more evolutionarily derived. Several clades are either primarily Neotropical or primarily Paleotropical but also have a few members distributed in the opposite hemisphere. Thus, we postulate multiple, independent dispersal and colonization events in several lineages.

Based on a worldwide phylogenetic framework filling the taxonomic gap of Madagascar and surrounding islands of the Western Indian Ocean (WIO), we revisited the systematics of grammitid fern species (Polypodiaceae). We also investigated the biogeographic origin of the extant diversity in Madagascar and estimated the relative influence of vicariance, long-distance dispersals (LDD) and in situ diversification. Phylogenetic inferences were based on five plastid DNA regions (atpB, rbcL, rps4-trnS, trnG-trnR, trnL-trnF) and the most comprehensive taxonomic sampling ever assembled (224 species belonging to 31 out of 33 recognized grammitids genera). 31 species from Madagascar were included representing 87% of the described diversity and 77% of the endemics. Our results confirmed a Paleotropical clade nested within an amphi-Atlantic grade. In addition, we identified three new major clades involving species currently belonging to Grammitis s.l., Ctenopterella and Enterosora. We resolved for the first time Grammitis s.s. as monophyletic, and Ctenopterella (newly tested here) and Enterosora as polyphyletic. The Neotropical genus Moranopteris was shown to also occur in Madagascar through a newly discovered species. Most importantly, we suggest a >30% inflation of the species number in the WIO due to the hidden diversity in >10 cryptic lineages, best explained by high morphological homoplasy. Molecular dating and ancestral areas reconstruction allowed identifying the Neotropics as the predominant source of LDD to the African-WIO region, with at least 12 colonization events within the last 20Ma. Repeated eastward migrations may be explained by transoceanic westerly winds transporting the dust-like spores. Tropical Asia s.l. would also have played a (minor) role through one dispersal event to Madagascar at the end of the Oligocene. Last, within the complex Malagasy region made of a mosaic of continental and oceanic islands located close to the African continent, we showed that contrary to theoretical expectations and empirical evidence in angiosperms, Africa does not act as a dispersal source and Madagascar seems to have a more important influence on the regional dynamics: we observed both in situ species diversification and dispersal out of Madagascar. This influence also extends beyond the region, since one dispersal event probably originated from Madagascar and reached the Subantarctic island of Amsterdam.

Aim To compare the species richness, and taxonomic and life‐form composition of tropical montane pteridophyte floras on two well‐documented sites: Mount (Mt) Kinabalu, Sabah, Borneo and Parque Nacional (PN) Carrasco, central Bolivia. Methods Using published lists, we compared the elevational distribution of overall species richness, specific pteridophyte families, and of life‐forms along both study sites. Additionally, we compared point‐diversity by establishing 108 plots of 400 m2 at PN Carrasco, and 15 such plots at Mt Kinabalu and three at a lowland site at Danum Valley in south‐eastern Sabah, Borneo (200 m). Results The numbers of species, genera, and families recorded on Mt Kinabalu were 14–23% higher than at PN Carrasco, most probably as a result of more intensive long‐term collecting activity. Opposed to this, species richness per 400 m2 plot was somewhat higher at PN Carrasco, especially amongst epiphytes at mid‐elevations. Overall, there was a remarkable similarity in the elevational distribution of species numbers, of individual pteridophyte families, and of life‐forms. Major differences included a more pronounced peak of species richness at 1500 m on Mt Kinabalu, considerably higher species numbers of Elaphoglossum at PN Carrasco and of Grammitidaceae at Mt Kinabalu, and a higher proportion of debris‐trapping epiphytes and lithophytic species at Mt Kinabalu and of terrestrial herbs at PN Carrasco. Main conclusions The majority of present‐day species of the studied pteridophyte floras evolved largely independently from about 66–100 common ancestors. The striking convergence of the pteridophyte floras of both sites indicates that the taxonomic and morphological composition of the pteridophyte floras is subject to selective pressure, and that specific pteridophyte families are evolutionarily pre‐disposed to occupy specific ecological niches.