Search

Previous phylogenetic analysis of ITS nrDNA sequence data for Arctotidinae species resolved a strongly supported clade containing all but one of the showy annual Arctotis species (informally designated the Arctotis Annual Clade). In the present study, phylogenetic relationships in the Arctotis Annual Clade were investigated by Bayesian inference and maximum parsimony analyses of cpDNA (trnT-trnL-trnF and trnH-psbA) and nrDNA (ITS) sequence data. The cpDNA and nrDNA phylogenies were notably incongruent. Arctotis venusta and a putative unnamed species (A. 'sp. B') were strongly supported as monophyletic by both data sets. The monophyly of A. leiocarpa was strongly supported by the ITS data set, whereas the remaining accessions formed a poorly resolved complex (the 'A. fastuosa complex'). Within the A. fastuosa complex, A. hirsuta was monophyletic with strong support in the ITS phylogeny. A statistical parsimony-derived cpDNA haplotype network resolved five broad groups of haplotypes and showed no consistent geographical structure, but species-specific haplotype lineages for A. venusta and A. sp. B were resolved. Arctotis fastuosa accessions were distributed among four haplotype groups. Incongruence between the data sets and poor resolution within the A. fastuosa complex may reflect reticulate evolution, ancestral polymorphism, and incomplete lineage sorting, in tandem with the low information content of the data sets. The greatest phenotypic diversification in the clade is in cypsela morphology. Comparison of cypsela morphology with the phylogenies suggests a general trend for reduction in the sizes of the cypsela, abaxial wings, pappus scales, and loss of pubescence during diversification. A revised taxonomy, integrating currently available evidence, accompanied by full descriptive accounts and a key to the taxa are presented. Eight species are recognized, including the nomenclatural novelties Arctotis chrysantha (sp. nov.) and Arctotis namibiensis (sp. nov.). The names Arctotis karasmontana, Venidium fugax, and Venidium macrocephalum are lectotypified. [ABSTRACT FROM AUTHOR]

This study investigates genetic diversity in three species of Ephemeroptera, one eurytopic and therefore widespread (Afroptilum sudafricanum) and two stenotopic and thus endemic (Demoreptus natalensis and Demoreptus capensis) species, all of which co-occur in the southern Great Escarpment, South Africa. Mitochondrial DNA was analysed to compare the genetic diversity between the habitat generalist and the two habitat specialists. Afroptilum sudafricanum showed no indication of population genetic structure due to geographic location, while both Demoreptus species revealed clear genetic differentiation between geographic localities and catchments, evident from phylogenetic analyses and high FST values from AMOVA. In addition, the phylogenetic analyses indicate some deeper haplotype divergences within A. sudafricanum and Demoreptus that merit taxonomic attention. These results give important insight into evolutionary processes occurring through habitat specialisation and population isolation. Further research and sampling across a wider geographic setting that includes both major mountain blocks of the Escarpment and lowland non-Escarpment sites will allow for refined understanding of biodiversity and associated habitat preferences, and illuminate comparative inferences into gene flow and cryptic speciation. [ABSTRACT FROM AUTHOR]

The dominance of a few staple crops (maize, rice, and wheat) in most agricultural systems hampers the application of interventions to improve food security and nutrition. Research and development attention has focused on improving the production and utilization of these crops, leaving other crops under‐researched and underutilized. Subsequently, there have been high malnutrition rates due to poor diet diversity, yet there are "opportunity crops" that remain under researched. The opportunity crops can unlock solutions to food insecurity, malnutrition, a lack of biodiversity, and indeed poor climate adaptation. The study explored diversification in agricultural systems to analyze whether reorientation of research investment to include under‐researched crops can increase nutrient gain and enhance dietary diversity. Research outputs benchmarked as the number of publications from three leading African universities, Nairobi, Pretoria, and Ghana, were related to crop diversity and nutrition of crops in five clusters: cereals, vegetables, legumes, roots and tubers, and nuts. The findings show that maize was the predominantly researched crop across the three institutions. Low research outputs were observed for pearl millet, finger millet, and yam across the three institutions: amaranth and nightshade (Pretoria), sweet potatoes (Pretoria and Ghana), Marama bean (Nairobi), and soya bean (Nairobi and Ghana). There was nutrient gain across all five clusters, particularly from under‐researched indigenous crops such as finger millet, amaranth, nightshade, yam, sweet potatoes, Marama bean, and soybean. Nutrient gain was contributed more by cereals and root and tuber crops from Pretoria, vegetables and nuts (Ghana), as well as legumes (Nairobi). The findings demonstrate that incorporating research on the least researched crops with successful integration of other research and development initiatives (policy and dissemination) can increase nutrition and improve dietary diversity. The nutrient gain will positively affect food security and nutrition, contributing to the achievement of Africa Agenda 2063, the United Nation's Sustainable Development Goals, and reducing food imports. The findings can inform research investment and decision across different institutions within the African continent. Research investment targeting crops such as finger millet, amaranthus, sweet potatoes, soya beans, and cashew nuts is needed considering the nutritional contribution, climate change adaptability, market potential, and biodiversity contribution. Further analysis should explore production, socio‐economic (marketability and income generation), and environmental gains (adaptive ability to climate change) for specific crops. The development of frameworks to guide the analysis of the nature and scope of factors affecting the contribution of these crops to food security and nutrition, as well as research on specific crops considering geographic distribution and institutional involvement, is also needed. [ABSTRACT FROM AUTHOR]

Chrysanthemoides monilifera Tourn. ex Medik is a noxious weed in Australia and New Zealand. It is a widespread species in southern Africa, where it shows considerable morphological variation that has resulted in a confusing infraspecific taxonomy. We use DNA sequence data from the nuclear Internal Transcribed Spacer (ITS) region from 78 samples of this species from its indigenous distribution range and 10 samples from Australia and New Zealand to determine the regions of origin of the invasive plants. These data are augmented by a smaller study using ISSR markers. Bayesian Inference analysis was somewhat resolved, with many weakly supported nodes. Clades with support tended to correspond to infraspecific taxonomic entities, and were geographically coherent. In contrast, a neighbour-net analysis was not as well resolved and indicated considerable reticulation. All analyses of ITS data retrieved two major clades corresponding to Western and Eastern distributions, with some overlap. Samples from New Zealand and Australia correspond to the taxon C. monilifera subsp. monilifera , and are resolved as most closely related to samples from the greater Cape Town area. Biological control agent populations for C. monilifera subsp. monilifera should be sourced from this region in order to avoid host plant incompatibility problems. [ABSTRACT FROM AUTHOR]

Faucaria tigrina (Haw.) Schwantes is a rare, threatened succulent found exclusively on the outskirts of Grahamstown, Eastern Cape, South Africa. There are three extant populations of the species; two large ones (approximately 300 and 620 adults) separated by under two kilometres, and a third very much smaller one slightly further away. Genetic theory expects that smaller, isolated populations face a loss in genetic variation through inbreeding and genetic drift and that as declining genetic variation is linked to a loss in fitness, this species may face extinction in the long term. This study used the ISSR-PCR genetic methods linked to an automated detection platform to determine if these populations are genetically distinct, and whether they are genetically depauperate. Two ISSR primers were used, and the automated detection system identified a total of 572 ISSR loci. An UPGMA clustering analysis showed each population to be genetically distinct, and that the genetic diversity of each population does not appear to be particularly low. F. tigrina is separable from the related Faucaria britteniae L. Bolus using the ISSR method, suggesting that this method may be appropriate for systematic studies in the Aizoaceae, which comprises many genera with closely related species. [ABSTRACT FROM AUTHOR]

Keywords: biodiversity; community ecology; conservation; environmental drivers; fragmentation; Southern Africa; species richness EN biodiversity community ecology conservation environmental drivers fragmentation Southern Africa species richness 784 787 4 09/02/22 20220901 NES 220901 INTRODUCTION Anthropogenic habitat modification is the single biggest cause of forest habitat loss (Alroy, 2017; Ewers & Didham, 2006; Fahrig, 2003). Thus, investigating the small mammal populations in South African forests is an important first step to understanding the effects of forest fragmentation on forest fauna (Lindenmayer et al., 2002). Patch occupancy and potential metapopulation dynamics of three forest mammals in fragmented Afromontane forests in South Africa. Four species were caught across the nine forest patches; I Michaelamys namaquensis i (Namaqua rock mouse), I Myosorex varius i (forest shrew) I Graphiurus murinus i (woodland dormouse) and I Mastomys natalensis senu lato i (multimammate mouse) (Table 2). [Extracted from the article]

Some plant species possess structures known as leaf domatia, which house mites. The association between domatia-bearing plants and mites has been proposed to be mutualistic, and has been found to be important in species of economic value, such as grapes, cotton, avocado and coffee. This is because leaf domatia affect the distribution, diversity and abundance of predatory and mycophagous mites found on the leaf surface. As a result, plants are thought to benefit from increased defence against pathogens and small arthropod herbivores. This study assesses the relative diversity and composition of mites on an economically important plant host (Coffea aribica) in comparison to mites found in a neighbouring indigenous forest in South Africa. Our results showed that the coffee plantations were associated with only predatory mites, some of which are indigenous to South Africa. This indicates that coffee plantations are able to be successfully colonised by indigenous beneficial mites. We also found an "edge effect", in that coffee trees at the edge of the plantation hosted fewer mite species. These results are a snap-shot from a single sampling period. Nonetheless, they highlight the potential importance of this mutualism in commercial crop species and the possible role of faunal exchanges between indigenous and exotic crop species. This study expands our understanding of the mite–plant mutualism in Southern Africa, a region where acarological studies are sparse. [ABSTRACT FROM AUTHOR]

A new phytoseiids species, Typhlodromus (Anthoseius) uhoneae sp.n. is described from plants with domatia. In addition, 8 known phytoseiid species also associated with plants with domatia are discussed. A key to all the South African species of the subgenus Anthoseius is given. [ABSTRACT FROM AUTHOR]

The Platypleurini is a large group of charismatic cicadas distributed from Cape Agulhas in South Africa, through tropical Africa, Madagascar, India and eastern Asia to Japan, with generic diversity concentrated in equatorial and southern Africa. This distribution suggests the possibility of a Gondwanan origin and dispersal to eastern Asia from Africa or India. We used a four‐gene (three mitochondrial) molecular dataset, fossil calibrations and molecular clock information to explore the phylogenetic relationships of the platypleurine cicadas and the timing and geography of their diversification. The earliest splits in the tribe were found to separate forest genera in Madagascar and equatorial Africa from the main radiation, and all of the Asian/Indian species sampled formed a younger clade nested well within the African taxa. The tribe appears to have diversified during the Cenozoic, beginning c. 50–32 Ma, with most extant African lineages originating in the Miocene or later, well after the breakup of the Gondwanan landmass. Biogeographical analysis suggests an African origin for the tribe and a single dispersal event founding the Asian platypleurines, although additional taxon sampling and genetic data will be needed to confirm this pattern because key nodes in the tree are still weakly supported. Two Platypleurini genera from Madagascar (Pycna Amyot & Audinet‐Serville, Yanga Distant) are found to have originated by late Miocene dispersal of a single lineage from Africa. The genus Platypleura is recovered as polyphyletic, with Platypleura signifera Walker from South Africa and many Asian/Indian species apparently requiring assignment to different genera, and a new Platypleura concept is proposed with the synonymization of Azanicada Villet syn.n. The genera Orapa Distant and Hamza Distant, currently listed within separate tribes but suspected of platypleurine affinity, are nested deeply within the Platypleurini radiation. The tribe Orapini syn.n. is here synonymized while the tribe Hamzini is pending a decision of the ICZN to preserve nomenclatorial stability. [ABSTRACT FROM AUTHOR]

The influence of fire regimes on soil microbial diversity in montane grasslands is a relatively unexplored area of interest. Understanding the belowground diversity is a crucial stepping-stone toward unravelling community dynamics, nutrient sequestration, and overall ecosystem stability. In this study, metabarcoding was used to unravel the impact of fire disturbance regimes on bacterial and arbuscular mycorrhizal fungal community structures in South African montane grasslands that have been subjected to an intermediate (up to five years) term experimental fire-return interval gradient. Bacterial communities in this study exhibited a shift in composition in soils subjected to annual and biennial fires compared to the controls, with carbon and nitrogen identified as significant potential chemical drivers of bacterial communities. Shifts in relative abundances of dominant fungal operational taxonomic units were noted, with Glomeromycota as the dominant arbuscular mycorrhiza observed across the fire-return gradient. A reduction in mycorrhizal root colonisation was also observed in frequently burnt autumnal grassland plots in this study. Furthermore, evidence of significant mutualistic interactions between bacteria and fungi that may act as drivers of the observed community structure were detected. Through this pilot study, we can show that fire regime strongly impacts bacterial and fungal communities in southern African montane grasslands, and that changes to their usually resilient structure are mediated by seasonal burn patterns, chemical drivers, and mutualistic interactions between these two groups. [ABSTRACT FROM AUTHOR]

Two new species of Indigofera L. (Leguminosae) are described from the Sneeuberg Centre of Floristic Endemism on the southern Great Escarpment, Eastern and Western Cape Provinces, South Africa. Both species are localised high-altitude endemics. Indigofera magnifica Schrire & V.R. Clark is confined to the summit plateau of the Toorberg--Koudeveldberg--Meelberg west of Graaff-Reinet, and complements other western Sneeuberg endemics such as Erica passerinoides (Bolus) E.G.H. Oliv. and Faurea recondita Rourke & V.R. Clark. Indigofera asantasanensis Schrire & V.R. Clark is confined to a small area east of Graaff-Reinet, and complements several other eastern Sneeuberg endemics such as Euryops exsudans B. Nord & V.R. Clark and E. proteoides B. Nord. & V.R. Clark. Based on morphology, both new species belong to the Cape Clade of Indigofera, supporting a biogeographical link between the Cape Floristic Region and the Sneeuberg, as well as with the rest of the eastern Great Escarpment. [ABSTRACT FROM AUTHOR]

Mitochondrial DNA sequences (1137 bp) of the cytochrome b gene and craniodental and craniometric data were used to investigate the evolutionary relationships of six putative rodent taxa of Otomys (family Muridae: subfamily Murinae: tribe Otomyini) co-occurring in the Western Cape and Eastern Cape provinces of South Africa. Phylogenetic analysis of 20 new sequences together with craniodental and craniometric characters of 94 adult skulls reveal the existence of a unique lineage of Otomys cf. karoensis (named herein Otomys willani sp. nov.) from the Sneeuberg Centre of Floristic Endemism in the southern Drakensberg Mountain Range. Craniometric analysis distinguished O. karoensis from O. willani and identified a further four localities in the range of the latter species. We document southern range extensions of both Sloggett's ice rat, Otomys sloggetti , and the vlei rat Otomys auratus to the Sneeuberg Mountain Range, in addition to appreciable genetic divergence between Sneeuberg and southern and central Drakensberg populations of O. sloggetti. Our results demonstrate parallel patterns of cryptic speciation in two co-occurring species complexes (Otomys irroratus s.l. and O. karoensis s.l.) associated closely with the boundaries of biomes (fynbos vs. grassland biomes) and geological formations (Cape Fold Belt vs. Great Escarpment). [ABSTRACT FROM AUTHOR]

South Africa's 800 km-long southern Great Escarpment hosts numerous endemic plant species only known from their type specimens or from very few records. This is a legacy of a 100-150 year lag between the pioneer work of 19th century botanists and repeat fieldwork in the 21st century. As a result, population and ecological data are lacking for many local endemic species. Here we report on the rediscovery of Lotononis harveyi B.-E.van Wyk 147 years after its original description, and provide the first detailed ecological notes on the poorly known shrub Macowania revoluta Oliv. Both species are locally endemic to the Great Winterberg-Amatholes (Eastern Cape Province). With only six known individuals, L. harveyi is recommended the conservation status of Critically Endangered, with fire (and potentially grazing) being the main population constraints. Macowania revoluta is locally abundant, and it is surprising that it has been so poorly collected in recent decades. It occupies an important local niche as a keystone montane wetland species, and its narrow distribution range -- combined with pressure from woody alien invasive species -- suggests that its conservation status should be Rare. The research further highlights the need for continued biodiversity field research along South Africa's poorly explored Great Escarpment. [ABSTRACT FROM AUTHOR]