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Abstract: This paper presents the first palynological results from subsurface strata of the Gedaref Formation, a succession of intercalated sandstones and mudstones in eastern Sudan. The top of the formation yielded a well preserved and fairly diversified sporomorph assemblage. Palm pollen, which are typical elements in contemporaneous West African coastal basins, were recorded in the present material, namely Longapertites, Mauritiidites, Monocolpites, Proxapertites and Spinizonocolpites. The coexistence of marker species such as Cristaeturites cristatus, Foveomonocolpites bauchiensis, Mauritiidites crassibaculatus, Monocolpites marginatus, Periretisyncolpites giganteus, Proteacidites sigalii, Proxapertites operculatus, Racemonocolpites cf. racematus, Retidiporites magdalenensis, Retitricolpites clarensis and Scabratriporites samoilovitchii indicates a Maastrichtian age for the top of the Gedaref Formation which was previously thought to be of Jurassic age. The occurrence of abundant structured phytoclasts, membraneous tissues and very little amorphous material suggests deposition in high energy fluvial settings close to the source vegetation. The frequent occurrence of pollen grains assigned to the Palmae group supports the prevalence of warm-humid conditions during the deposition of the studied sediments. [Copyright &y& Elsevier]

Sub-Saharan Africa, with its hot and humid climate, is a conducive zone for tick proliferation. These vectors pose a major challenge to both animal and human health in the region. However, despite the relevance of emerging diseases and evidence of tick-borne disease emergence, very few studies have been dedicated to investigating zoonotic pathogens transmitted by ticks in this area. To raise awareness of the risks of tick-borne zoonotic diseases in sub-Saharan Africa, and to define a direction for future research, this systematic review considers the trends of research on tick-borne bacteria, parasites, and viruses from 2012 to 2023, aiming to highlight the circulation of these pathogens in ticks, cattle, sheep, goats, and humans. For this purpose, three international databases were screened to select 159 papers fitting designed inclusion criteria and used for qualitative analyses. Analysis of these studies revealed a high diversity of tick-borne pathogens in sub-Saharan Africa, with a total of 37 bacterial species, 27 parasite species, and 14 viruses identified. Among these, 27% were zoonotic pathogens, yet only 11 studies investigated their presence in humans. Furthermore, there is growing interest in the investigation of bacteria and parasites in both ticks and ruminants. However, research into viruses is limited and has only received notable interest from 2021 onwards. While studies on the detection of bacteria, including those of medical interest, have focused on ticks, little consideration has been given to these vectors in studies of parasites circulation. Regarding the limited focus on zoonotic pathogens transmitted by ticks, particularly in humans, despite documented cases of emerging zoonoses and the notable 27% proportion reported, further efforts should be made to fill these gaps. Future studies should prioritize the investigation of zoonotic pathogens, especially viruses, which represent the primary emerging threats, by adopting a One Health approach. This will enhance the understanding of their circulation and impact on both human and animal health. In addition, more attention should be given to the risk factors/drivers associated to their emergence as well as the perception of the population at risk of infection from these zoonotic pathogens. [ABSTRACT FROM AUTHOR]

Tick-borne pathogens (TBPs) are a major impediment to the health, welfare, and production of small ruminants across the world, including Africa. Comprehensive information about the epidemiology of TBPs infecting sheep and goats across Africa is lacking. Therefore, this study was undertaken to determine the prevalence through a meta-analysis of selected TBPs in blood DNA from domestic sheep and goats in Africa obtained using molecular-based methods. The literature review was done according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines using five English electronic databases (PubMed, Science Direct, Springer Link, Web of Science, and African Journals Online (AJOL). The search was performed with no restriction in time through to 18th January 2023. Of the 63 full-text articles subjected to eligibility, only 30 articles met the eligibility criteria and were included in the review. The overall pooled prevalence of selected TBPs varied considerably between host species (sheep vs. goats), with Anaplasma ovis (44.50 vs. 48.40%), Ehrlichia ruminantium (5.50 vs. 2.00%), Coxiella burnetii (4.40 vs. 1.70%), Borrelia theileri in sheep (5.20%), Babesia ovis (1.70% vs. 1.90%), Theileria ovis (40.50% vs 10.00%), T. separata (1.00% vs 1.00%) and T. lestoquardi in sheep (8.40%). However, the prevalence of the selected TBPs was generally higher in sheep compared to goats. Several genetic loci were targeted in the characterization of tick-borne pathogens, such as 16S rDNA, groEL, and msp4 for Anaplasma ovis, pCS20 for Ehrlichia ruminantium, Insertion Sequence (IS1111) for Coxiella burnetii, flaB (flagellin) and 16S rRNA for Borrelia theileri, 5.8S rRNA and 18S rRNA for Babesia/Theileria, as well as the utilization of numerous PCR variants including conventional polymerase chain reaction (PCR), nested-PCR, qPCR, Loop-mediated isothermal amplification (LAMP), and reverse line blotting (RLB). In conclusion, A. ovis was the most widely distributed and prevalent TBP affecting small ruminants within the continent. Hence, this warrants adequate attention towards early diagnosis and treatment of infected animals as well as the control of the tick vectors involved in their transmission. [ABSTRACT FROM AUTHOR]

Premise of research. Several morphotypes of well-preserved legume leaflet compressions are known from the early Miocene Mush plant assemblages from the northwestern plateau of Ethiopia. One of these morphotypes represents a member of the Amherstieae tribe (subfamily Detarioideae) and is prevalent in the assemblage. Morphological and epidermal micromorphological characteristics are sufficient to identify it to genus. The evolutionary and biogeographic significance of the early Miocene occurrence of this genus in the uplands of Ethiopia is explored. Methodology. Fossil laminae were compared with herbarium specimens and leaf cuticle preparations to determine their likely identity. Pivotal results. Morphological and micromorphological characteristics support recognition of a new fossil species of Anthonotha (Leguminosae: Detarioideae: Amherstieae: Berlinia clade), herein named Anthonotha shimaglae Pan, Jacobs, Currano, Estrella, Herendeen et Burgt sp. nov. Characteristics include symmetrical, untoothed leaflets with pulvinate petiolules, short acuminate leaflet tips, eucamptodromous secondary venation, an abaxial epidermal surface possessing sinuous anticlinal cell walls, paracytic stomatal complexes, abundant trichome bases, papillate periclinal cell walls, and an adaxial epidermal surface possessing highly sinuous anticlinal cell walls. A. shimaglae represents the earliest-known macrofossil of the genus. The occurrence of this new species with other Detarioideae legumes, including Englerodendron mulugetanum , and a morphotype representing Berlinia or Isoberlinia in the early Miocene Mush plant assemblages is more analogous to high-rainfall evergreen forests of Central Africa today than East African forest types. Conclusions. Early Miocene Mush fossils include the common occurrence of an extinct species of legume, herein named Anthonotha shimaglae. Prehistoric forests of the Ethiopian plateau may represent ancestral sources of currently disjunct and perhaps relictual wet forest taxa in tropical montane and coastal forests of eastern Africa today, as well as potential evolutionary sources of the Guineo-Congolian forested region. [ABSTRACT FROM AUTHOR]

Anaplasma species, belonging to the family Anaplasmataceae in the order Rickettsiales, are obligate intracellular bacteria responsible for various tick-borne diseases of veterinary and human significance worldwide. With advancements in molecular techniques, seven formal species of Anaplasma and numerous unclassified species have been described. In Africa, several Anaplasma species and strains have been identified in different animals and tick species. This review aims to provide an overview of the current understanding of the molecular epidemiology and genetic diversity of classified and unclassified Anaplasma species detected in animals and ticks across Africa. The review also covers control measures that have been taken to prevent anaplasmosis transmission on the continent. This information is critical when developing anaplasmosis management and control programs in Africa. [ABSTRACT FROM AUTHOR]

The early Eocene (∼56–48 Myr ago) is characterized by high CO2 estimates (1,200–2,500 ppmv) and elevated global temperatures (∼10°C–16°C higher than modern). However, the response of the hydrological cycle during the early Eocene is poorly constrained, especially in regions with sparse data coverage (e.g., Africa). Here, we present a study of African hydroclimate during the early Eocene, as simulated by an ensemble of state‐of‐the‐art climate models in the Deep‐time Model Intercomparison Project (DeepMIP). A comparison between the DeepMIP pre‐industrial simulations and modern observations suggests that model biases are model‐ and geographically dependent, however, these biases are reduced in the model ensemble mean. A comparison between the Eocene simulations and the pre‐industrial suggests that there is no obvious wetting or drying trend as the CO2 increases. The results suggest that changes to the land sea mask (relative to modern) in the models may be responsible for the simulated increases in precipitation to the north of Eocene Africa. There is an increase in precipitation over equatorial and West Africa and associated drying over northern Africa as CO2 rises. There are also important dynamical changes, with evidence that anticyclonic low‐level circulation is replaced by increased south‐westerly flow at high CO2 levels. Lastly, a model‐data comparison using newly compiled quantitative climate estimates from paleobotanical proxy data suggests a marginally better fit with the reconstructions at lower levels of CO2. Plain Language Summary: Approximately 50 Myr ago, a period known as the early Eocene, atmospheric carbon dioxide levels were significantly higher than today, and were more similar to what they could be in the future, if efforts to reduce human greenhouse gas emissions are unsuccessful. However, rainfall changes during this period are less well understood, especially over data‐sparse regions such as Africa. Here, a collection of state‐of‐the‐art climate models are used to study African rainfall during this period, comparing the simulations first to present‐day African rainfall (to validate the models), second to varying levels of atmospheric carbon dioxide, and lastly to newly compiled reconstructions of early Eocene rainfall (from plant fossils). The main findings are that although the models can reproduce present‐day rainfall over Africa, and compare reasonably well with the reconstructions, there is no clear rainfall signal when atmospheric carbon dioxide is increased. Nevertheless, the combination of a different continental configuration, vegetation, topography, and atmospheric carbon dioxide leads to changing rainfall patterns, connected to temperature and low‐level wind changes. Key Points: State‐of‐the‐art climate models are used to study African hydroclimate during the early Eocene (approximately 50 Myr ago)With increasing levels of CO2, there are changes to African precipitation, due to dynamical changes such as low‐level circulationA comparison between the models and newly compiled climate estimates shows a marginally better match at lower levels of CO2 [ABSTRACT FROM AUTHOR]

Aim: The roles of geodynamics, climatic variability and landscape evolution in shaping aquatic biodiversity patterns on the African continent remain poorly understood. We studied the geographical origin and phylogenetic relationships of an Afrotropical freshwater snail genus to examine the role of drainage evolution on diversification and range evolution. The relevance of fish provinces in bio‐regionalization of invertebrates was explored, as well as the evolution of habitat specificity. Location: Africa including Madagascar. Taxon: Lanistes (Gastropoda: Ampullariidae). Methods: Based on a sampling covering the entire geographical range, we reconstructed a fossil‐calibrated multi‐locus molecular phylogeny using maximum likelihood and Bayesian inference approaches. After applying species delimitation methods, we estimated ancestral areas and habitats and examined rates of diversification through time using lineage through time plots. Results: RAxML and MrBayes analyses resulted in highly congruent topologies and a strongly supported phylogeny. Our BEAST analysis indicate that Lanistes probably originated in the Eocene about 50 Ma and the most recent common ancestor (MRCA) of all 23 Lanistes OTUs in our study may have inhabited an area including the Central African and adjacent Lower Guinean biogeographical regions. A steeper increase in species accumulation from the middle Miocene (c. 15 to 10 Ma), followed by a decrease towards the present was found. Sympatry and jump dispersal were the common cladogenetic events and only a single anagenetic dispersal event was detected. The biogeographical analyses further suggest that Madagascar was colonized from East Africa and that the Zambezi River was colonized at least twice independently. Seven species are confined to rivers and three live exclusively in lakes. The estimation of ancestral habitats suggested that the MRCA of all Lanistes probably evolved in a riverine habitat. Main conclusions: The diversification of Lanistes started in the Eocene and occurred at a constant pace apart from a possible climate‐related increase in the Miocene. This study highlights the significance of temporal geographical isolation of river systems and subsequent reconnection in clade diversification and of jump dispersal in range evolution. More comparative analyses across various taxa are needed to obtain a better understanding of African freshwater biodiversity. [ABSTRACT FROM AUTHOR]

Fossil records of endemic plants play an important role in recognizing the floristic history of East Asia and thereby facilitate the conservation of plant diversity in the region. However, the fossil record of many extant East Asian endemic genera remains poorly documented thus far. Here, we report an infructescence fossil of an East Asian endemic genus, Sladenia (Sladeniaceae), from the early Miocene of southeastern Yunnan, China. The fossil is characterized by: (i) dichasial cymes; and (ii) flask‐shaped ovary with dense subparallel ribs on the surface extending from the base to the distal end of the united style. It represents the first fossil record of Sladenia in Asia, showing that the genus was established in the region at least by the early Miocene. Given that a much older fossil record of Sladeniaceae has been reported from Africa and the sister group of Sladenia is distributed only in Africa, Sladenia is not likely of East Asian origin. The present endemic status of Sladenia was possibly achieved by regional extirpation in Africa and taking refuge in East Asia. This case thus supports the "Museum" rather than "Cradle" hypothesis for the genesis of high plant species in the flora of East Asia. A comparison of the present fossil with extant Sladenia infructescence shows morphological stasis from the early Miocene to present. Such evolutionary tardiness might have resulted in the reduced fitness of the genus, which further caused its current endangered situation. [ABSTRACT FROM AUTHOR]