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The genus Encephalartos is entirely endemic to Africa, and like most cycad species, the genus is at risk of extinction. One of the threats jeopardising the future of the genus is reproduction failure, a failure that is still poorly understood. Our objective was to investigate what predisposes Encephalartos species to seed damages through predation, a potential cause of reproduction failure. We collected functional traits of 430 individuals of Encephalartos villosus, as well as data on pre‐dispersal seed predation, habitat type and elevation in the Origi Gorge Nature Reserve, South Africa. Then, we analysed our data by fitting a structural equation model. We found that plants tend to be taller when moving from open to close habitat, whereas plant height tends to increase along elevation. In addition, taller plants tend to have more leaves, and plant canopy size shows significant positive relationship with elevation, plant height and number of leaves. These findings suggest a leaf height–canopy dimension strategy perhaps in response to environmental stresses imposed by elevation. We tested the effects of habitat types on seed production. Although there were significantly more seeds in open habitats, open habitats showed the lowest proportion of predated seeds. Finally, we tested the effects of elevation on seed production. We found that seed production decreases along elevation while the proportion of predated seeds increases. Under the resource concentration hypothesis, these findings (where there are more resources, predation is low) are unexpected, suggesting rather that it is the resource dilution effect that matches the pre‐dispersal seed predation patterns in our study area. We suggest that anthropogenic pressures at lower elevation due to easy access may cause seed predators to shift towards higher elevation where they cause heavier damage to seed, thus perhaps contributing to the extinction risk of the genus Encephalartos. [ABSTRACT FROM AUTHOR]

Justicieae is the most taxonomically complex tribe in Acanthaceae. Here, we sequenced the plastome of Ecbolium viride, a medicinally important species. The genome was analyzed with previously reported plastome of Justiceae. The plastome of E. viride has quadripartite structure with a length of 151 185 bp. The comparative genomic analyses revealed no structural inversion in Justiceae and some regions (rpoC2, ycf2, ycf1, ndhH rps16-trnQ-UGG, and trnL-CAA-ycf15) exhibiting a significant level of nucleotide divergence. The positive selection analyses revealed that some species in the tribe have undergone adaptive evolution. The visualization of the boundaries between the single copy and inverted repeat regions revealed that Justiceae chloroplast genome experienced some levels of variation, which give an insight into the evolution of the species. The longest genome was in the earliest diverged taxa of the tribe Pseuderanthemum haikangense and from this genome, a series of contraction and expansion occurred contributing to the evolution of other lineages. The plastome-based phylogeny revealed and confirmed the monophyly of Justiceae, polyphyly of Justicia and supported the tribal classification Graptophyllinae, Tetrameriinae, and Isoglossinae. We proposed that Declipterinae should be treated as subtribe and the status of Justiciinae can only be confirmed after the resolution of the polyphyletic Justicia. [ABSTRACT FROM AUTHOR]

Background and aims Taxonomists are primary actors of biodiversity assessment. At the same time, there is awareness by the taxonomic community at large that the field is going through a crisis, sometimes referred to as the 'taxonomic impediment'. Coupled with the ongoing biodiversity crisis, or 6th mass extinction, this biodiversity impedance puts at risk the target set in the Convention on Biological Diversity's (CBD) Global Biodiversity Framework vision 2050, which calls for urgent action to '... put biodiversity on a path to recovery by 2030 for the benefit of planet and people'. This risk is particularly pronounced in tropical African countries where taxonomic studies are done on an ad hoc basis. In this study, our aim is to investigate the historical trends in botanical exploration of vascular plants in Nigeria and forecast the near-term (50-year) description of presently unknown species, which we use to discuss scenarios of taxonomic effort that may be necessary for a comprehensive biodiversity assessment in the country. Methods The study is based on a dataset from the World Checklist of Vascular Plants, containing all vascular plant species reported to occur in Nigeria. We fit nested Bayesian time series regressions to estimate the long-term trend in the rate of description of vascular plant species in Nigeria. From these models, we use an ensemble forecast to estimate the number of species descriptions by the year 2070, and then evaluate the description rates per taxonomist required to meet this estimate under different totals of active taxonomists. Key results We find a striking difference in species description between Nigerian botanists and their foreign counterparts, with the former contributing relatively small numbers. Additionally, only a fraction of the authors involved in describing Nigeria's vascular plants are of indigenous origin. Our study reveals that the number of new species described annually exhibits a long-term increasing trend, with an average of 19.5 species described per year. However, after taking into account year-to-year variability and the number of taxonomists active in a given year, the long-term trend in species descriptions credibly declines over time. While the number of authors involved in describing species has generally increased over time, it has remained stable since the 1950s. Predictions for the number of new species descriptions by 2070 vary by model, with an ensemble prediction estimating 1140 species descriptions, but ranging from 1004 to 2239 between individual models. Conclusions The study estimates that current levels of taxonomic activity should lead to a 20 % increase in known species of vascular plants in Nigeria over the next 50 years, which is still probably an underestimate of the true, unknown species richness. Urgent action is needed to address the taxonomic impediment so that local taxonomic studies in tropical African countries can achieve the CBD's Global Biodiversity Framework vision 2050. Here, we outline some key pathways to achieving this goal. [ABSTRACT FROM AUTHOR]

Alien invasive species are problematic both economically and ecologically, particularly on islands. As such, understanding how they interact with their environment is necessary to inform invasive species management. Here, we ask the following questions: What are the main functional traits that correlate with invasion success of alien plants on Robben Island? How does phylogenetic structure shape biotic interactions on the island? Using multiple approaches to explore these questions, we found that alien invasive species flower later during the year and for longer period, although flowering phenology was sensitive to alternative starting date. Additionally, we observed that alien invasive species are mostly abiotically pollinated and are generally hermaphroditic whilst their native counterparts rely on biotic pollinators, flower earlier, and are generally dioecious, suggesting that alien invasive and native species use different ecological niches. Furthermore, we found a facilitative interaction between an alien invasive legume and other invasive plants as predicted by the invasional meltdown hypothesis, but this does not influence the phylogenetic structure of plant communities. Finally, phylogenetically diverse set of native species are less receptive to alien invasive species. Collectively, our findings reveal how biotic interactions and phylogenetic relatedness structure alien invasive--native co-existence. Key words: Acacia cyclops, biological invasions, evolutionary history, functional traits, invasional meltdown, niche partition. Les especes envahissantes sont problematiques tant sur le plan economique qu'ecologique, particulierement sur des iles. En tant que tel, il est necessaire de comprendre comment elles interagissent avec leur environnement pour guider leur gestion. Dans ce travail, les auteurs posent les questions suivantes : Quels sont les principaux caracteres fonctionnels qui sont correles avec le potentiel envahissant des especes exotiques sur Robben Island? Comment la structure phylogenetique faconne-t-elle les interactions biotiques sur l'ile? A l'aide d'approches multiples, les auteurs trouvent que les especes exotiques fleurissent plus tard et pendant une plus longue periode, bien que la phenologie de la floraison etait sensible a une date alternative de debut de floraison. De plus, les auteurs observent que les especes envahissantes sont principalement sujettes a une pollinisation abiotique et sont generalement hermaphrodites, tandis que les especes indigenes beneficient de pollinisateurs biotiques, fleurissent plus tot et sont generalement dioiques, ce qui suggere que les especes exotiques et indigenes occupent des niches ecologiques differentes. Aussi, une interaction facultative entre une legumineuse envahissante et d'autres plantes envahissantes, tel que predit sur la base de l'hypothese de l'effondrement des especes indigenes, a ete observee, mais celle-ci n'influence pas la structure phylogenetique des communautes vegetales. Finalement, des communautes de plantes indigenes qui sont diversifiees sur le plan phylogenetique sont moins sujettes a l'envahissement par des especes exotiques. Ensemble, ces resultats revelent comment les interactions biotiques et la parente phylogenetique influencent la coexistence entre especes exotiques et indigenes. [Traduit par la Redaction] Mots-cles : Acacia cyclops, invasions biologiques, histoire evolutive, caracteres fonctionnels, effondrement des especes indigenes., Introduction The stability and productivity of ecosystems, as well as their ability to provide a diverse set of ecological services, correlate with their phylogenetic structure (Cadotte et al. 2008, 2009; [...]

Our understanding of how the phylogenetic tree of fishes might be affected by the ongoing extinction risk is poor. This is due to the unavailability of comprehensive DNA data, especially for many African lineages. In addition, the ongoing taxonomic confusion within some lineages, e.g., Cyprinidae, makes it difficult to contribute to the debate on how the fish tree of life might be shaped by extinction. Here, we combine COI sequences and taxonomic information to assemble a fully sampled phylogeny of the African Cyprinidae and investigate whether we might lose more phylogenetic diversity (PD) than expected if currently threatened species go extinct. We found evidence for phylogenetic signal in extinction risk, suggesting that some lineages might be at higher risk than others. Based on simulated extinctions, we found that the loss of all threatened species, which approximates 37% of total PD, would lead to a greater loss of PD than expected, although highly evolutionarily distinct species are not particularly at risk. Pending the reconstruction of an improved multi-gene phylogeny, our results suggest that prioritizing high-EDGE species (evolutionary distinct and globally endangered species) in conservation programmes, particularly in some geographic regions, would contribute significantly to safeguarding the tree of life of the African Cyprinidae. Key words: African freshwater ecosystems, conservation, DNA barcoding, EDGE, IUCN Red List. L'impact possible de l'extinction en cours sur l'arbre phylogenetique des poissons est mal connu. Cela decoule de l'indisponibilite de donnees d'ADN completes, particulierement chez des groupes africains. De plus, la confusion qui persiste au sein de certains groupes, p. ex. les Cyprinidae, rend difficile les contributions au debat sur la facon dont l'arbre des poissons pourrait etre affecte par l'extinction. Dans ce travail, les auteurs ont combine les sequences COI et les informations taxonomiques pour assembler une phylogenie bien echantillonnee des Cyprinidae africains et pour etudier si la disparition des especes presentement menacees pourrait entrainer une perte de diversite phylogenetique (DP) plus grande qu'attendue. Les auteurs ont trouve des evidences d'un signal phylogenetique en matiere de risque d'extinction, ce qui suggere que certains groupes seraient plus a risque que d'autres. Sur la base d'extinctions simulees, les auteurs ont trouve que l'extinction de toutes les especes menacees, soit environ 37 % de la DP, menerait a une perte de DP plus grande qu'attendue, tandis que les especes tres distinctes sur le plan evolutif ne seraient pas particulierement a risque. En attendant la reconstruction d'une phylogenie multigenique amelioree, les resultats suggerent qu'il faudrait prioriser les especes EDGE (<< Evolutionary Distinct and Globally Endangered >>) dans les programmes de conservation, particulierement au sein de certaines regions geographiques, afin de contribuer de maniere importante a la sauvegarde de la diversite phylogenetique chez les Cyprinidae africains. [Traduit par la Redaction] Mots-cles : ecosystemes d'eau douce africains, conservation, codage a barres de l'ADN, EDGE, liste rouge de l'IUCN., Introduction Evidence that we are losing biodiversity at an unprecedented rate is now piling up (Vamosi and Vamosi 2008; Barnosky et al. 2011; Ceballos et al. 2015). For example, one-fifth [...]

Abstract: Although a standard DNA barcode has been identified for plants, it does not always provide species-level specimen identifications for investigating important ecological questions. In this study, we assessed the [...]