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PREMISE OF THE STUDY:: Our goal was to infer the phylogenetic relationships and historical biogeography of the genus Dryopteris with a focus on taxa in sub‐Saharan Africa and neighboring islands. In general, little is known about the relationships between African fern species and their congeners in other geographic regions, and our aim was to determine whether the sub‐Saharan African species of Dryopteris are monophyletic and evolved within Africa or arrived there via repeated dispersals into Africa from other regions. METHODS:: We obtained sequence data for five chloroplast markers from 214 species of Dryopteris and 18 outgroups. We performed phylogenetic and molecular dating analyses using a Bayesian relaxed clock method in BEAST with fossil and secondary calibration points and estimated ancestral ranges for the genus globally by comparing multiple models in BioGeoBEARS. KEY RESULTS:: We found that 22 of 27 accessions of sub‐Saharan African Dryopteris belong to a large clade of 31 accessions that also includes taxa from Indian and Atlantic Ocean islands. Additional accessions of taxa from our regions of interest have Asian, Hawaiian, European, or North American species as their closest relatives. CONCLUSIONS:: The majority of sub‐Saharan African Dryopteris species are descended from a shared common ancestor that dispersed to Africa from Asia approximately 10 Ma. There have been subsequent dispersal events from the African mainland to islands in the Atlantic and Indian Oceans, including Madagascar. Several additional species are estimated to have descended from ancestors that reached Africa via separate events over the last roughly 20 million years. [ABSTRACT FROM AUTHOR]

The Finnish Red Lists from 2000 and 2010 were used to calculate for the first time the national Red List Index for the order Lepidoptera and different Lepidoptera families with data from 2245 species., We grouped species according to their primary habitats and analysed each habitat's RLI as well., The overall RLI was significantly negative, reflecting the worsening of the group as a whole in the country., A significant negative trend was found for families Tortricidae, Gelechiidae and Hesperiidae and for coastal habitats., We also report that 76 Lepidoptera species newly established a population in Finland between 2000 and 2010, probably expanding northwards driven by climate warming. [ABSTRACT FROM AUTHOR]

The International Union for Conservation of Nature (IUCN) Red List Index (RLI) is recognized as one of the key indicators of trends in the status of species. The red-list assessment done by Finnish authorities of species in Finland is taxonomically one of the most extensive national assessments. We used the Finnish Red Lists from 2000 and 2010 to calculate for the first time the national RLIs for 11 taxonomic groups at different trophic levels and with different life cycles. The red-list index is calculated on the basis of changes in red-list categories and indicates trends in the status of biological diversity of sets of species. The RLI value ranges from 0 to 1. The lower the value the faster the set of species is heading toward extinction. If the value is 1, all species in the set are least concern and if the value is 0, all species are (regionally) extinct. The overall RLI of Finnish species decreased. This means that, in Finland, these taxonomic groups were heading toward extinction faster in 2010 than in 2000. Of the analyzed groups of organisms, RLIs of 5 decreased and RLIs of 6 increased. At the national level, the RLIs and status trends varied markedly between species groups. Thus, we concluded that generalizations on the basis of RLIs of a few taxa only may yield a biased view of ongoing trends in the status of biological diversity at the species level. In addition, one overall RLI that includes many different species groups may also be misleading if variation in RLI among species groups is not considered and if RLI values are not presented separately for each group. Aplicación del Índice de la Lista Roja a Nivel Nacional para Grupos de Especies Múltiples [ABSTRACT FROM AUTHOR]

The phylogenetic relationships of liverworts were reconstructed using the sequence data of four genome regions including rbcL, rps4 and trnL-F of the chloroplast and 26S large subunit ribosomal rRNA gene of the nucleus, and 90 characters of morphological, ultrastructural and developmental aspects. The taxa sampled consisted of 159 species including 135 liverworts (108 genera, 54 families and 29 suborders), 13 mosses, two hornworts, seven vascular plants and two charophyte algae. Analyses based on maximum parsimony using both direct optimization (POY) and static alignment (NONA), as well as Bayesian inference (MrBayes) were done. All the data sets were analyzed simultaneously. Our study confirms that liverworts compose a monophyletic group which consists of three classes. The class Treubiopsida including both Treubia and Haplomitrium is resolved as the earliest diverging liverwort lineage. Blasia and the complex thalloids are assigned to the Marchantiopsida, under which Blasiidae and Marchantiidae are divided. Marchantiidae include Sphaerocarpales and Marchantiales. The simple thalloid and leafy liverworts form the Jungermanniopsida, which is further divided to subclasses Pelliidae subclassis nov., Metzgeriidae and Jungermanniidae. Metzgeriidae here is defined to include only Metzgeriaceae, Aneuraceae and Vandiemeniaceae, and is the sister group to the leafy liverworts. The leafy liverworts Jungermanniidae include the orders Pleuroziales, Porellales and Jungermanniales. It is assumed that the Porellales and the Jungermanniales have split early, at least in the Jurassic period. In the Porellales, the diversification rate may have remained relatively constant for long periods of time but speeding up only recently within some of the families, associated with an explosive radiation of angiosperms. The Jungermanniales are most probably a recently diversified group which has attained the greatest profusion of structure and the most remarkable diversity of leaf development and protective devices for maturing sporophytes. A detailed classification scheme for liverworts is presented. © The Willi Hennig Society 2006. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Location Taxon Methods Results Main Conclusions Ferns are globally distributed, yet the number of studies examining the historical evolution of African taxa is relatively low. Investigation of the evolution of African fern diversity is critical in order to understand patterns and processes that have global relevance (e.g., the pantropical diversity disparity [PDD] pattern). This study aims to examine when and from where a globally distributed fern lineage arrived in sub‐Saharan Africa, to obtain a better understanding of potential processes contributing to patterns of diversity across the region.Global, sub‐Saharan Africa.Asplenium (Aspleniaceae).We analysed five loci from 537 Asplenium taxa using a maximum likelihood (IQ‐Tree) phylogenetic framework. For age estimation, we performed penalised likelihood as implemented in treePL, and executed a Bayesian analysis using BEAST. Biogeographical analyses were carried out using BioGeoBEARS.Most dispersals into Africa occurred within the last ~55 myr, with the highest diversity of sub‐Saharan African taxa concentrated in two clades, each of which descended from an Asian ancestor. Additional dispersals to sub‐Saharan Africa can be found throughout the phylogeny. Lastly, potential cryptic species diversity exists within Asplenium as evidenced by several polyphyletic taxa.We recover multiple dispersals of Asplenium to sub‐Saharan Africa, with two major lineages likely diversifying after arrival. [ABSTRACT FROM AUTHOR]

The Red List Index (RLI) measures change in the aggregate extinction risk of species. It is a key indicator for tracking progress toward nine of the Aichi and many proposed post‐2020 Global Biodiversity Framework Targets. Here, we consider two formulations of the RLI used for reporting biodiversity trends at national scales. Disaggregated global RLIs measure changing national contributions to global extinction risk and are currently based on five taxonomic groups, while national RLIs measure changing national extinction risk and are based on taxonomic groups assessed multiple times in country. For 74% of nations, the disaggregated global RLI is currently based on three or fewer taxonomic groups. Meanwhile, national RLIs from selected pilot countries Finland, South Africa, and Brazil are computed from twelve, eight, and nine taxonomic groups, respectively. The national RLI and the disaggregated global RLI measure different aspects of biodiversity, in that the former detects national trends in populations of species for which each country is responsible while the latter provides standardized comparisons of nations' contributions to the global extinction risk of the same species groups. As governments commit to the post‐2020 Global Biodiversity Framework, we encourage them to monitor a standard set of taxonomic groups representing different biomes using both RLI formulations to ensure effective target tracking and accurate feedback on their conservation investments. [ABSTRACT FROM AUTHOR]

Species differ in their biological susceptibility to extinction, but the set of traits determining susceptibility varies across taxa. It is yet unclear which patterns are common to all taxa, and which are taxon-specific, with consequences to conservation practice. In this study we analysed the generality of trait-based prediction of extinction risk across terrestrial (including freshwater) vertebrates, invertebrates and plants at a global scale. For each group, we selected five representative taxa and within each group we explored whether risk can be related to any of 10 potential predictors. We then synthesized outcomes across taxa using a meta-analytic approach. High habitat specificity was a consistent predictor across vertebrates, invertebrates and plants, being a universal predictor of risk. Slow life-history traits – large relative offspring size, low fecundity, long generation length –, and narrow altitudinal range were also found to be good predictors across most taxa, but their universality needs to be supported with additional data. Poor dispersal ability was a common predictor of extinction risk among invertebrate and plant taxa, but not consistently among vertebrates. The remaining traits (body size, microhabitat verticality, trophic level, and diet breadth) were useful to predict extinction risk but only at lower taxonomical levels. Our study shows that despite the idiosyncrasies among taxa, universal susceptibility to extinction exists and several traits might influence extinction risk for most taxa. Informing conservation prioritization at lower taxonomic scales should however include taxon-specific trait-based predictors of extinction risk. [ABSTRACT FROM AUTHOR]

The article presents a study of the vascular land plant called woodland ferns (Dryopteris). Topics discussed include a description of the plant group and their distribution in various geographic regions of the world, their evolutionary position and unique aspects of biology, the author's recommendations for future research on the influence of hybridization on the plant's taxonomic classification.