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Premise: Increases in genome size in plants—often associated with larger, low‐density stomata and greater water‐use efficiency (WUE)—could affect plant ecophysiological and hydraulic function. Variation in plant genome size is often due to polyploidy, having occurred repeatedly in the austral sedge genus Schoenus in the Cape Floristic Region (CFR), while species in the other major schoenoid genus in the region, Tetraria, have smaller genomes. Comparing these genera is useful as they co‐occur at the landscape level, under broadly similar bioclimatic conditions. We hypothesized that CFR Schoenus have greater WUE, with lower maximum stomatal conductance (gwmax) imposed by larger, less‐dense stomata. Methods: We investigated relationships between genome size and stomatal parameters in a phylogenetic context, reconstructing a phylogeny of CFR‐occurring Schoeneae (Cyperaceae). Species' stomatal and functional traits were measured from field‐collected and herbarium specimens. Carbon stable isotopes were used as an index of WUE. Genome size was derived from flow‐cytometric measurements of leafy shoots. Results: Evolutionary regressions demonstrated that stomatal size and density covary with genome size, positively and negatively, respectively, with genome size explaining 72–75% of the variation in stomatal size. Larger‐genomed species had lower gwmax and C:N ratios, particularly in culms. Conclusions: We interpret differences in vegetative physiology between the genera as evidence of more‐conservative strategies in CFR Schoenus compared to the more‐acquisitive Tetraria. Because Schoenus have smaller, reduced leaves, they likely rely more on culm photosynthesis than Tetraria. Across the CFR Schoeneae, ecophysiology correlates with genome size, but confounding sources of trait variation limit inferences about causal relationships between traits. [ABSTRACT FROM AUTHOR]

The fundamental value of universal nomenclatural systems in biology is that they enable unambiguous scientific communication. However, the stability of these systems is threatened by recent discussions asking for a fairer nomenclature, raising the possibility of bulk revision processes for "inappropriate" names. It is evident that such proposals come from very deep feelings, but we show how they can irreparably damage the foundation of biological communication and, in turn, the sciences that depend on it. There are four essential consequences of objective codes of nomenclature: universality, stability, neutrality, and transculturality. These codes provide fair and impartial guides to the principles governing biological nomenclature and allow unambiguous universal communication in biology. Accordingly, no subjective proposals should be allowed to undermine them. [ABSTRACT FROM AUTHOR]

This article provides an overview of the biodiversity and evolution of African flora. Africa is home to a diverse range of ecosystems and has a rich variety of vascular plants, with over 65,000 recorded species. However, the cataloging of African plant diversity is uneven, with some regions well-documented and others barely explored. The article also explores the biogeographic history of African plants, the role of fire in shaping the flora, and the impact of climate change on plant diversity. The authors emphasize the need for conservation efforts specific to Africa, as the processes that have shaped its flora differ from those in other parts of the world. They also highlight the gaps in our understanding of African plant diversity and call for further research and data collection. [Extracted from the article]

Background and Aims The quartz fields of the Greater Cape Floristic Region (GCFR) are arid and island-like special habitats, hosting ~142 habitat-specialized plant species, of which 81 % are local endemics, characterized by a rapid turnover of species between and among sites. We use several phylogenetic community metrics: (1) to examine species diversity and phylogenetic structure within and among quartz fields; (2) to investigate whether quartz field specialists are evolutionarily drawn from local species pools, whereas the alternative hypothesis posits that there is no significant evolutionary connection between quartz field specialists and the local species pools; and (3) to determine whether there is an association between certain traits and the presence of species in quartz fields. Methods We sampled and developed dated phylogenies for six species-rich angiosperm families (Aizoaceae, Asteraceae, Crassulaceae, Cyperaceae, Fabaceae and Santalaceae) represented in the quartz field floras of southern Africa. Specifically, we focused on the flora of three quartz field regions in South Africa (Knersvlakte, Little Karoo and Overberg) and their surrounding species pools to address our research questions by scoring traits associated with harsh environments. Key Results We found that the Overberg and Little Karoo had the highest level of species overlap for families Aizoaceae and Fabaceae, whereas the Knersvlakte and the Overberg had the highest species overlap for families Asteraceae, Crassulaceae and Santalaceae. Although our phylogenetic community structure and trait analyses showed no clear patterns, relatively low pairwise phylogenetic distances between specialists and their local species pools for Aizoaceae suggest that quartz species could be drawn evolutionarily from their surrounding areas. We also found that families Aizoaceae and Crassulaceae in Knersvlakte and Little Karoo were phylogenetically even. Conclusions Despite their proximity to one another within the GCFR, the studied areas differ in their species pools and the phylogenetic structure of their specialists. Our work provides further justification for increased conservation focus on these unique habitats under future scenarios of global change. [ABSTRACT FROM AUTHOR]

Background and Aims The Greater Cape Floristic Region is one of the world's biodiversity hotspots and is considered poor in polyploids. To test this assumption, ploidy variation was investigated in a widespread Cape shrub, Dicerothamnus rhinocerotis (renosterbos, Asteraceae). The aim was to elucidate the cytotype distribution and population composition across the species range, and to assess differences in morphology, environmental niches and genetics. Methods Ploidy level and genome size were determined via flow cytometry and cytotype assignment was confirmed by chromosome counting. Restriction site-associated DNA sequencing (RADseq) analyses were used to infer genetic relationships. Cytotype climatic and environmental niches were compared using a range of environmental layers and a soil model, while morphological differences were examined using multivariate methods. Key Results The survey of 171 populations and 2370 individuals showed that the species comprises diploid and tetraploid cytotypes, no intermediates and only 16.8 % of mixed populations. Mean 2C values were 1.80–2.06 pg for diploids and 3.48–3.80 pg for tetraploids, with very similar monoploid genome sizes. Intra-cytotype variation showed a significant positive correlation with altitude and longitude in both cytotypes and with latitude in diploids. Although niches of both cytotypes were highly equivalent and similar, their optima and breadth were shifted due to differences mainly in isothermality and available water capacity. Morphometric analyses showed significant differences in the leaves and corolla traits, the number of florets per capitulum, and cypsela dimensions between the two cytotypes. Genetic analyses revealed four groups, three of them including both cytotypes. Conclusions Dicerothamnus rhinocerotis includes two distinct cytotypes that are genetically similar. While tetraploids arise several times independently within different genetic groups, morphological and ecological differences are evident between cytotypes. Our results open up new avenues for questions regarding the importance of ploidy in the megadiverse Cape flora, and exemplify the need for population-based studies focused on ploidy variation. [ABSTRACT FROM AUTHOR]

The Committee on Institutional Votes was established at the XIX International Botanical Congress (IBC), in Shenzhen in 2017, with the mandate to maintain a list of institutions and their allocated votes for the upcoming IBC, the next of which will be the XX IBC in Madrid in July 2024. Institutions worldwide were informed of the mechanism to apply for one or more institutional votes or to request a change in previously allocated votes. Forty applications were received by the Committee, of which 28 were from institutions new to the list, 9 requested an increase in allocated votes and 3 requested no change to allocated votes. All requests were accepted, two of them partly so. Adjustments were also made for two institutions that had been closed or transferred. The Committee sent a draft of this report together with the revised list for Madrid to the General Committee for final approval, as required by the International Code of Nomenclature for algae, fungi, and plants. The General Committee approved the list, which is now presented here. The total number of institutions on the list is 572; the total number of institutional votes that could potentially be exercised is 970. Only 30.4% of institutions exercised their votes in Shenzhen in 2017. Institutions are urged to exercise their votes in Madrid in 2024, and instructions for this are provided. [ABSTRACT FROM AUTHOR]

The rapid loss of biodiversity, coupled with difficulties in species identification, call for innovative approaches to assess biodiversity. Insects make up a substantial proportion of extant diversity and play fundamental roles in any given ecosystem. To complement morphological species identification, new techniques such as metabarcoding make it possible to quantify insect diversity and insect--ecosystem interactions through DNA sequencing. Here we examine the potential of bulk insect samples (i.e., containing many non-sorted specimens) to assess prokaryote and eukaryote biodiversity and to complement the taxonomic coverage of soil samples. We sampled 25 sites on three continents and in various ecosystems, collecting insects with SLAM traps (Brazil) and Malaise traps (South Africa and Sweden). We then compared our diversity estimates with the results obtained with biodiversity data from soil samples from the same localities. We found a largely different taxonomic composition between the soil and insect samples, testifying to the potential of bulk insect samples to complement soil samples. Finally, we found that non-destructive DNA extraction protocols, which preserve insect specimens for morphological studies, constitute a promising choice for cost-effective biodiversity assessments. We propose that the sampling and sequencing of insect samples should become a standard complement for biodiversity studies based on environmental DNA. Key words: environmental DNA, COI mtDNA, non-destructive DNA extraction, metabarcoding, 16S rDNA, 18S rDNA. La perte rapide de biodiversite, combinee avec les difficultes liees a l'identification des especes, necessitent le developpement d'approches innovatrices pour mesurer la biodiversite. Les insectes constituent une proportion substantielle de la diversite et jouent des roles fondamentaux dans tous les ecosystemes. Pour complementer l'identification des especes fondee sur la morphologie, de nouvelles techniques comme le metacodage a barres rendent possible la quantification de la diversite des especes d'insectes et des interactions insectesecosystemes via le sequencage de l'ADN. Ici, les auteurs examinent la possibilite d'examiner des echantillons composites (contenant plusieurs specimens non-tries) pour mesurer la biodiversite en procaryotes et en eucaryotes ainsi que pour complementer la couverture taxonomique des echantillons de sol. Les auteurs ont echantillonne 25 sites sur trois continents dans differents ecosystemes, en piegeant des insectes a l'aide de pieges SLAM (au Bresil) ou Malaise (en Afrique du Sud et en Suede). Ils ont ensuite compare les estimes de diversite avec les resultats obtenus pour la biodiversite au sein des sols provenant des memes localites. Les auteurs ont trouve une composition taxonomique largement differente entre les echantillons de sol et d'insectes, ce qui atteste de l'utilite des echantillons composites d'insectes pour complementer les echantillons de sol. Finalement, ils ont trouve que les protocoles d'extraction d'ADN non-destructifs, lesquels preservent les specimens pour des examens morphologiques, constituent un choix prometteur pour des mesures de la biodiversite qui sont economiques. Les auteurs proposent que l'echantillonnage et le sequencage d'insectes devraient devenir un complement standard aux etudes de biodiversite fondees sur l'ADN environnemental. [Traduit par la Redaction] Mots-cles : ADN environnemental, COI ADNmt, protocole d'extraction d'ADN non-destructif, metacodage a barres, ADNr 16S, ADNr 18S., Introduction Quantification of biological diversity is crucial for many biological and societal applications, including biogeography and ecosystem services, understanding biological interactions, and for designing conservation and management strategies. But quantifying [...]

The land use and land cover (LULC) changes driven by the growing demands of mankind have a considerable effect on ecosystem services and functions. The study was carried out in the north-eastern highlands of Ethiopia to (1) analyze the effect of LULC changes between 1984 and 2021 and (2) assess the spatiotemporal variations in ecosystem service values (ESVs) and elasticity in response to LULC changes. Using Landsat imageries from 1984 to 2021, the spatiotemporal changes in LULC were evaluated with supervised image classification using maximum likelihood algorithm in ArcGIS software. Six LULC types were subsequently categorized, with overall accuracy and Kappa coefficients above 87% and 0.87, respectively. The ESVs were then estimated based on the Benefit Value Transfer (BVT) approach employing modified conservative value coefficients. The findings revealed a significant increase in cultivated land (9759.1ha) and built-up area (10174.41ha) during the stipulated periods and a drop in other land use types. The forest loss gradually decreased from 4.1% in the second period (1991–2001) to 0.58% in the third (2001–2021), compared to the first of the 1.1% conversion rates. Similarly, the proportion of grassland and water bodies steadily reduced over the stipulated periods, by 1.15% and 2.3% per annum, respectively. The overall loss of ESVs in the study landscape was estimated to be 54.4 million US$ (67.3%), drastically decreasing from 80.3 million US$ in 1984 to 26.4 million US$ in 2021, driven by the declining area coverage of water bodies, grassland, and forestland. Regardless of the loss, the ecosystem functions of hydrological regulation (37.2, 35.0, 6.1, and 5.1 US$ ha-1yr-1), water supply (14.5, 13.6, 2.4, and 2 US$ ha-1yr-1), and food production (9.8, 10.0, 9.1, and 9.9 US$ ha-1yr-1) contributed the most to the total ESV of each year while disturbance regulation and cultural values were the least throughout the study periods. The coefficient of sensitivity (CS) analysis revealed that our estimates were relatively robust. The findings further showed that human-dominated land-uses at the expense of natural ecosystems are the primary drivers of LULC transitions and the ensuing loss of ecosystem services in the region. Thus, this calls for intensive work on more effective land use policies that encourage an integrated management approach, with a focus on safeguarding the sustainability of natural ecosystems. [ABSTRACT FROM AUTHOR]

Ecologically specialized plants are expected to be at greater risk of extinction than generalists due to climate change. Such risk is greatest in biodiversity hotspots such as the Greater Cape Floristic Region (GCFR), which accommodates both ecological specialists and generalists. Thesium L., a genus with the highest number of species in Santalaceae and the most diverse in Africa, offers an appropriate system for evaluating both the correlates of range extent and specialization and the relative extinction risks associated with both. We hypothesized that range size, ecological specialization, and consequent climatically modulated extinction risks are all phylogenetically structured, such that climate change will precipitate a disproportionate loss of phylogenetic diversity in the GCFR Thesium. Past and future species distribution ranges were predicted using MaxEnt models based on present‐day occurrences and environmental conditions. Of the 101 Thesium species modeled, 70% have had large range sizes during the Last Glacial Maximum (LGM), 50% currently have a large range size, and future conditions are predicted to allow 40% to obtain large range sizes. Between the LGM and the present, 17% of species are thought to have undergone a contraction of available range space in the present time whereas 37% are expected to expand their ranges into the future, while 51% of species will experience range contractions. Of the 65 species currently ranked as Least Concern in the South African Red List, 24% will likely shift into higher extinction risk categories. Interestingly, 8.5% of ecological specialists, although having experienced a range reduction from the LGM to the present, are predicted to persist in the face of future climate change. However, the range extent, ecological specialization, and extinction risk are phylogenetically random and therefore should have a negligible impact on the phylogenetic diversity of the GCFR Thesium. [ABSTRACT FROM AUTHOR]

As recently circumscribed, Sesamum was rendered monophyletic by including the three segregate genera Ceratotheca , Dicerocaryum and Josephinia. Here, the monophyly of Sesamum and the currently accepted infrageneric taxa was tested using expanded phylogenetic analyses. In addition, nine taxonomically useful morphological characters were optimized on the resulting phylogenetic tree to assess their evolutionary pattern. The phylogenetic analyses support the expanded circumscription of Sesamum and the monophyly of Sesamum section Sesamum relative to Sesamum sections Aptera, Ceratotheca , Chamaesesamum , Dicerocaryum , Josephinia and Sesamoptera. Most sections were retrieved as monophyletic, except Sesamum section Ceratotheca which was shown to be paraphyletic. Character reconstruction infers the ancestor of Sesamum to have had an erect growth habit, simple leaves with entire margins, ovaries with incompletely divided locules, indehiscent capsules that are oblong-quadrangular in lateral view with a beaked apex and winged seeds. Relative to the ancestral states, Sesamum has dehiscent fruits and fully divided locules as synapomorphies, with reversals to the ancestral state (indehiscence, undivided locules) in Sesamum sections Josephinia and Dicerocaryum. The absence of trichomes on mature vegetative parts and the development of lobed leaves are synapomorphies for Sesamum section Sesamopteris. Characters such as dentate and lobulate leaf margins and discoid fruit with horn-like protrusions are homoplastic in Sesamum. Dated phylogeny and ancestral range estimation suggest a southern African origin for the genus with subsequent diversification to tropical Africa, India and Australia. Sesamum has an estimated crown age of 38.1 ± 5.2 Myr with subsequent dispersal scenarios into tropical Africa, Asia and Australia during the Miocene from 24.5 Mya. Dispersal, rather than continental vicariance, is the probable explanation for the pantropical distribution of Sesamum. [ABSTRACT FROM AUTHOR]

Tinnea gombea, endemic to the Sudan savanna grasslands in northern Nigeria, is described and illustrated. We used integrative evidence from morphological characters, ecology and molecular phylogenetic data. The new species is morphologically and ecologically similar to T. barteri and T. aethiopica, but can be readily delimited from these taxa by unique characters including a subshrub growth habit, leaves alternate to subopposite, blades lanceolate, apically acuminate, inflorescences raceme, bearing solitary flowers in upper leaf and bract axils, lilac to purplish dusky flowers and the inflated fruits dehiscent. The distribution and habitat of T. gombea are also distinctive, being restricted to the Sudan savanna, while the two most similar species are widespread in tropical Africa. Additionally, molecular phylogenetic assessments using nrITS and chloroplast trnL-F, matK and rbcL support the placement of T. gombea as a distinct species. Tinnea gombea is here assessed as Critically Endangered due to its small population size and restriction to a small area lacking conservation prioritization. [ABSTRACT FROM AUTHOR]