Central Angola Research Articles

Patterns of Grewia (Malvaceae) diversity across geographical scales in Africa and Madagascar.

Quantifying spatial species richness is useful to describe biodiversity patterns across broad geographical areas, especially in large, poorly known plant groups. We explore patterns and predictors of species richness across Africa in one such group, the palaeotropical genus Grewia L. (Malvaceae). Grewia species richness was quantified by extracting herbarium records from GBIF and Tropicos and creating geographical grids at varying spatial scales. We assessed predictors of species richness using spatial regression models with 30 environmental variables. We explored species co-occurrence in Madagascar at finer resolutions using Schoener's index and compared species range sizes and International Union for Conservation of Nature status among ecoregions. Lastly, we derived a trait matrix for a subset of species found in Madagascar to characterize morphological diversity across space. Grewia species occur in 50 countries in Africa, with the highest number of species in Madagascar (93, with 80 species endemic). Species richness is highest in Madagascar, with ≤23 Grewia species in a grid cell, followed by coastal Tanzania/Kenya (≤13 species) and northern South Africa and central Angola (11 species each). Across Africa, higher species richness was predicted by variables related to aridity. In Madagascar, a greater range in environmental variables best predicted species richness, consistent with geographical grid cells of highest species richness occurring near biome/ecoregion transitions. In Madagascar, we also observe increasing dissimilarity in species composition with increasing geographical distance. The spatial patterns and underlying environmental predictors that we uncover in Grewia represent an important step in our understanding of plant distribution and diversity patterns across Africa. Madagascar boasts nearly twice the Grewia species richness of the second most species-rich country in Africa, which might be explained by complex topography and environmental conditions across small spatial scales.

New species of Asclepias (Apocynaceae), Baphia (Leguminosae), Cochlospermum (Bixaceae) and Endostemon (Lamiaceae) from the Kalahari sands of Angola and NW Zambia, with one new combination in Vangueria (Rubiaceae).

Four new species are described from central and eastern Angola and adjacent NW Zambia. All occur in Kalahari sand savannas rich in endemic and more widely distributed geoxylic suffrutices. Despite being known from very few collections, the conservation status of one of these new species is assessed as Least Concern, as these grasslands are nutrient-poor, are in remote sparsely populated areas, and are not threatened with conversion to agriculture. The remaining three are treated as Data Deficient. In addition, one new combination is provided for Ancylanthosrubiginosus Desf. under Vangueria as V.rubiginosa (Desf.) Lantz is an illegitimate later homonym. We also make orthographic corrections to specific epithets commemorating Ilse von Nolde, a collector who made important collections from Quela in Malange in the 1930s.

The Rise of Modern Angolan Parties – UNITA and a Failed Growth Model

During the 1960’s the extension of the capitalist mode of production fastened the disintegration of the Angolan “traditional society”. Angola’s high-rate growth was made possible because huge oil and diamond rents were taxed and reinvested locally. With these “development polices” which the colonial State expected would support the fading branches of agro-industry and stabilize the political status quo, there was a shift of the main social contradiction. It was no longer a “central” versus “tributary” cleavage but rather labour-capital one within “modern society”. Ideologically, although transitional languages expressed by “racial” or cultural phenotypes were still in use, there was now room for different political standings. The nationalist movements, which started as small dissent fractions within the “central society“ were therefore forced to change their tactics in order to encompass the support of rising classes and their social mobility aspirations. This paper focuses on UNITA, whose operational circumstances (guerrilla-based operations inside Central Angola) made it easier to fit into the moving social landscape. Some evidences of UNITA ideological stand and of its 1974-1975 electoral behaviour (a period when the guerrilla movements were facing metamorphose into political parties) show that the factor “ethnicity”, widely used as a key variable of African politics, needs reviewing, at least in this particular time in Angola.

A bioavailable strontium isoscape of Angola with implications for the archaeology of the transatlantic slave trade

The region of present-day Angola was one of the main areas from which millions of enslaved Africans were abducted and forced to migrate to the Americas during the transatlantic slave trade. Strontium isotope (87Sr/86Sr) analysis is a useful tool in reconstructing large-scale human movements across geologically distinct landscapes in archaeological and forensic contexts. However, the absence of environmental 87Sr/86Sr reference data from Angola hinders the use of 87Sr/86Sr analysis in provenance studies related to Angola, especially in identifying the geographic origin of enslaved people in the African Diaspora. Here, we measured 101 plant samples from most, yet not all, major geological units to draft the first bioavailable 87Sr/86Sr map (isoscape) for Angola using a machine learning framework. Our results suggest that the 87Sr/86Sr ratios in Angola span a large range from 0.70679 to 0.76815 between the different geological units. Specifically, the high average 87Sr/86Sr ratios of 0.74097 (±0.00938, 1 SD) found in the Angola Block of central Angola, are distinctly more radiogenic than any previously published bioavailable 87Sr/86Sr ratios for western Central and West Africa. However, these match the 87Sr/86Sr ratios previously published for human enamel samples from four historic slavery contexts in the Americas. We demonstrate that our strontium isoscape of Angola greatly improves the ability to assess the possible origins of enslaved African individuals discovered outside of Africa and encourage the future use of emerging African isoscapes in the study of life histories within the slave trade.

A HIMU volcanic belt along the SW African coast (∼83–49 Ma): New geochemical clues to deep mantle dynamics from carbonatite and silica-undersaturated complexes in Namibia

The origin of carbonatitic and highly silica-undersaturated volcanism, common along the SW coast of Africa extending from Angola through Namibia to the tip of South Africa, is still poorly understood. Here we present new geochemical data (major and trace element and Sr-Nd-Pb-Hf-O-C isotopes) from the Agate Mountain calcio- to magnesio‑carbonatites (∼83 Ma), Dicker Willem calcio‑carbonatites (49 Ma) and Swakopmund basanitic plugs (76–72 Ma) along the coast of Namibia that were emplaced after the EMI (enriched mantle one) type Etendeka flood basalts. The trace element and isotopic composition of Agate Mountain carbonatites and Swakopmund basanites indicate that they were derived from a HIMU-type (high time-integrated 238 U/ 204 Pb with radiogenic Pb isotope ratios) magma source, similar to the St. Helena global HIMU endmember in the South Atlantic. The Agate Mountain carbonatites form part of the late-stage Walvis Ridge HIMU hotspot track overlying the EM1-type Walvis Ridge basement forming part of the Tristan-Gough hotspot track. The Dicker Willem carbonatites, however, extend to higher 206 Pb/ 204 Pb than St. Helena, but have similar 206 Pb/ 204 Pb to Mangaia HIMU lavas in the Pacific. Compared to Mangaia HIMU, the Dicker Willem carbonatites with mantle-type O and C isotopes have higher 207 Pb/ 204 Pb and 87 Sr/ 86 Sr but lower 143 Nd/ 144 Nd, suggesting it may represent a new HIMU endmember flavor. The HIMU carbonatitic and silica-undersaturated rocks form a belt of age-progressive volcanic tracks, including: 1) from the Walvis Ridge, through NW Namibia to central Angola, 2) from the Vema Seamount via Dicker Willem carbonatite to Gibeon kimberlites and carbonatites, 3) from the Namaqualand to Bushmanland and to Warmbad volcanic centers in northwestern South Africa, and 4) along the older end of the Shona EMI-type volcanic track extending into South Africa. Geochemical and seismic tomographic data suggest that the EMI and HIMU mantle plumes are generated from different geochemical domains at the base of the lower mantle. The Tristan-Gough, Discovery and Shona EM1 volcanic tracks are derived from a common low-velocity anomaly (superplume-like structure with three branching arms) ascending from the outer margin, possibly lower primoridal layer, of the African large low-shear-velocity province (LLSVP). Seismic low-velocity anomalies can be traced from beneath the belt of HIMU volcanism to an internal and shallower part of the LLSVP, located ∼900–1200 km east of the outer LLSVP margin and suggest that HIMU-type (possibly subducted oceanic lithospheric) material overlies EMI-type (possibly primordial) material in the internal part of the LLSVP. • A HIMU-like volcanism belt along the southwest Africa. • The HIMU-like volcanic complexes form age-progressive volcanic tracks. • EMI and HIMU mantle plumes are from different domains in the lower mantle.

A new species of red toad, Schismaderma Smith, 1849 (Anura: Bufonidae), from central Angola.

A new species of red toad, from the previously monotypic genus Schismaderma, is described. The new species was found in Malanje Province, and seems endemic to central Angola, occurring approximately 500 km west of the closest known records of Schismaderma carens. Unusual adult colouration and geographical distance to remaining S. carens populations suggested specific differentiation. In an integrative approach, we compared the red toads from central Angola with S. carens from across the entire range, including molecular data, morphology of adults and tadpoles, and male advertisement calls. Phylogenetic analysis based on mitochondrial (12S, 16S, COI) and nuclear (CXCR4, RAG1) markers, retrieved the Angolan clade as monophyletic, and revealed intra-specific substructuring among the remaining Schismaderma. Genetic distances supported specific differentiation of the central Angolan material compared with other S. carens. Adults from the new Angolan species have bolder ventral patterning and smaller body size than S. carens. No obvious differences were detected between the tadpoles and the advertisement calls of the two Schismaderma species. This discovery adds to the knowledge of the herpetofauna of the Angolan Miombo woodlands, a poorly understood ecoregion, and likely more biodiverse than previously assumed. The result of past river basin dynamics in central Angola likely led to the evolution of this new species of Schismaderma.

Chronicles of Bailundo: a fragmentary account in Umbundu of life before and after Portuguese colonial rule

Abstract‘Chronicles of Bailundo’ is a fragmentary account of life in Bailundo, Central Angola. The manuscript, whose authorship and exact date are unknown, is available at the archives of the American Board of Commissioners for Foreign Missions (ABCFM) at Houghton Library, Harvard University. It was written in Umbundu, the vernacular spoken in Bailundo, by North American Congregational missionaries between 1903 and the 1930s. Although the source mentions no dates, it refers roughly to the period between the seventeenth century and the gradual establishment of Portuguese colonial rule and Christian missions in the late nineteenth and early twentieth centuries. It gives access to both the Umbundu then spoken in Bailundo and the perspective of Umbundu-speaking subjects on what it was like to live in this polity. The source addresses socio-cultural, political and economic aspects of life in Bailundo as well as significant historical events, such as the Bailundo War (1902–03). The text in Umbundu, published as supplementary material with this article, has been transcribed, translated into Portuguese and English, and annotated. The version published following the main introduction of the article presents an annotated sample of the source in English. The full version, published as supplementary material, comprises the complete original in Umbundu, its complete annotated translation into English, and a complete annotated translation into Portuguese. The article addresses the authorship, contents, form and context of production of the source.

Frost‐driven lower treelines in Angola and their implications for tropical forest–grassland mosaics

AbstractQuestionsForest–grassland boundaries in the tropics are primarily interpreted as driven by fire and herbivory. So far, frost has received little attention as driver of tropical vegetation boundaries. Here, we study mid‐altitudes in south‐central Africa and ask the following questions: (a) is there a lower treeline between grasslands and forests on the Angolan Plateau; (b) if so, do topoclimatic differences play a role in it; and (c) what do our results imply for tropical highlands globally?LocationThe Angolan Plateau (10°–16°S and 13°–21° E).MethodsWe mapped vegetation by applying a supervised support vector machine‐based classification on a Landsat satellite image. We used a 1,000‐m spaced point grid to extract the mean vertical distribution of the vegetation units from a digital elevation model. The topographic position of each point was calculated using a channel network approach. Microclimatic data were collected across topographic gradients at two sites along the Plateau. Analyses focussed on the number of nights where temperature dropped below 0℃, median and minimum temperatures, and diurnal temperature ranges.ResultsLower treelines separate Miombo forests from geoxyle grasslands in all major valley systems. Treelines are located 150–200 m below the headwater divides. Nocturnal outgoing net long‐wave radiation and resulting cold‐air pooling cause frequent frosts in the valleys during the dry season. Topography controls frost patterns, with minima of down to −7.5℃ and diurnal temperature amplitudes up to 40℃.ConclusionsThe results show that vegetation patterns in central Angola are shaped by frost. The processes causing frost depend on air humidity. Drier atmosphere and lower global temperatures indicate a longer frost season, lower minima and frost extending to lower elevations and latitudes for the Pleistocene. Pleistocene forest fragmentations and the rise of endemism‐rich grasslands in comparable tropical highlands worldwide may be explained by crossing thermic thresholds via increasing seasonal aridity.

Buchholzia coriacea: AN OFTEN NEGLECTED AFRICAN PLANT WITH MULTIFARIOUS ETHNOPHARMACOTHERAPEUTIC POTENTIALS

The evergreen shrub Buchholzia coriacea (Wonderful cola), which belongs to the Capparidaceae family, is found in Cameroon, Central African Republic, Gabon, Congo, Angola, Nigeria, and Ghana, among other places. Diarrhea, malaria, rheumatism, ulcers, worm infestation, asthma and cough, diabetes, hypertension, mental problems, and impotence were among the conditions for which traditional medicine believed it to be a useful alternative treatment. Some of its ethnomedicinal knowledge had been ethnopharmacologically verified and published in scientific publications. As a result, the emphasis of this study is on a current evaluation of its verified ethnomedicinal activities, which will serve as a research horizon for current and future academics.

Geochemistry of subtropical arenosols from Kuito region (Angola). Urbanization effects and environmental implications

The city of Kuito, in a tropical highland region of central Angola, has grown rapidly over the past few decades. Although industrialization is minor, the city evolved with poor planning and road traffic have been soaring. Physicochemical properties of two sets of soil samples, natural and urban, are compared to assess the transformations achieved during the last decades in association with human occupation. Compared to natural soil, urban soils have significantly higher pH and electrical conductivity. Because of the association with quartz-rich sandy units, regional arenosols are impoverished in most minor and trace elements. Urban soil has significantly lower contents of Al, Ga, Sc, V and Zr and significantly higher contents of Ca, Na, P and several potentially toxic elements (PTE) than natural soil. A comparison with natural background levels reveals PTE enrichments ranked as Cd > Zn > Sb > Ba > Pb > Hg > Cu > Sn. In peripheric areas of Kuito, urbanization-related geochemical disturbances are mainly limited to enrichment in Ca, Na and P, and depletion in elements that tend to concentrate in fine-grained fractions; but soils in central areas tend to hold significant, although variable, amounts of PTE. PTE enrichment relative to a Si-rich background partially explain the high values of PLI (pollution load index) and PERI (potential ecological risk index), with environmental deterioration promoted by local contents of Pb, Zn, Cu and Cr. However, only the concentrations of Pb, and occasionally As, Ba, Cu, Hg and Zn, surpass available environmental guideline values. The present work shows that even without industrial activities, recent urbanization changed tropical arenosol geochemistry and can be responsible for significant enrichment in PTE.

New insights into the taxonomic status, distribution and natural history of De Witte’s Clicking Frog (Kassinula wittei Laurent, 1940)

Kassinula is a monotypic genus of small frog in the family Hyperoliidae, only represented by Kassinula wittei. This species morphologically resembles both Kassina Girard, 1853 and Afrixalus Laurent, 1944, and its taxonomic status has been debated for decades. It has previously been subsumed within Kassina, and is currently placed as a sister genus to Afrixalus, although it has not been included in any phylogenetic studies until now. This species is poorly represented in museum collections and is only known from fewer than 35 specimens from southern Democratic Republic of the Congo and adjacent Zambia. Newly collected material from central Angola, a range extension of 400–800 km west of previously known localities, allowed us to revisit the taxonomic placement of the genus with the aid of phylogenetic analysis and shed light on its geographic distribution, morphology and natural history. Although our phylogenetic analysis is limited to a single mitochondrial gene (16S), we place Kassinula in the subfamily Hyperoliinae and closely related to Afrixalus, with a high degree of confidence. Further phylogenetic studies are needed before formally synonymising Afrixalus with Kassinula.

Spatial and Temporal Trends of Burnt Area in Angola: Implications for Natural Vegetation and Protected Area Management

Fire is a key driver of natural ecosystems in Africa. However, human activity and climate change have altered fire frequency and severity, with negative consequences for biodiversity conservation. Angola ranks among the countries with the highest fire activity in sub-Saharan Africa. In this study, we investigated the spatial and temporal trends of the annual burnt area in Angola, from 2001 to 2019, and their association with terrestrial ecoregions, land cover, and protected areas. Based on satellite imagery, we analyzed the presence of significant trends in burnt area, applying the contextual Mann–Kendall test and the Theil–Sen slope estimator. Data on burnt areas were obtained from the moderate-resolution imaging spectroradiometer (MODIS) burnt area product and the analyses were processed in TerrSet. Our results showed that ca. 30% of the country’s area burned every year. The highest percentage of annual burnt area was found in northeast and southeast Angola, which showed large clusters of decreasing trends of burnt area. The clusters of increasing trends were found mainly in central Angola, associated with savannas and grasslands of Angolan Miombo woodlands. The protected areas of Cameia, Luengue-Luiana, and Mavinga exhibited large areas of decreasing trends of burnt area. Conversely, 23% of the Bicuar National Park was included in clusters of increasing trends. Distinct patterns of land cover were found in areas of significant trends, where the clusters of increasing trends showed a higher fraction of forest cover (80%) than the clusters of decreasing trends (55%). The documentation of burnt area trends was very important in tropical regions, since it helped define conservation priorities and management strategies, allowing more effective management of forests and fires in countries with few human and financial resources.

A dwarf among giants: phylogenetic position of the elusive Angolan Adder (Bitis heraldica) and biogeographic affinities of Angolan Afromontane regions

ABSTRACT The Angolan Adder, Bitis heraldica (Bocage, 1889), is endemic to the Angolan central plateau and is one of the most poorly known and rarely observed species of African snakes. The phylogenetic placement of B. heraldica within the four subgenera of the genus Bitis (Bitis, Macrocerastes, Calechidna, Keniabitis) has been problematic. The few recent taxonomic and phylogenetic revisions dealing with African viperids and the genus Bitis have not included this species, resulting in the default acceptance of B. heraldica as member of the subgenus Calechidna, based on similar morphology and size. During a survey in Huambo Province, central Angola, we collected the first specimen of this species in the past 65 years, allowing us to examine its phylogenetic relationships to other Bitis using multigene Bayesian and maximum likelihood analyses of all species of Bitis, except B. harenna. Contrary to expectations that B. heraldica is a member of the subgenus Calechidna, our results unambiguously place B. heraldica among members of the subgenus Macrocerastes, which contains the largest-bodied species of the genus. The placement of B. heraldica within Macrocerastes raises interesting questions about body-size evolution in viperids and contributes to a better understanding of biogeographic patterns in south-western Africa, and particularly Angola.

Medicinal plants used by ‘root doctors’, local traditional healers in Bié province, Angola

Ethnopharmacological relevanceThis study is one of the first post-civil war efforts to document traditional botanical knowledge in Bié province, central Angola, in a first step to bring more studies on the use of medicinal plant resources in this area so as to bring new insights into Angolan bio-cultural diversity. Aim of the studyExamine the variety of plant species used for medical purposes, as well as characterize their social and cultural values. Also, it is aimed to compare their uses in the studied region with those in Sub-Saharan Africa and report new ethnomedicinal uses. Materials and methodsWe documented traditional medicinal plant knowledge among professional herbalists in two areas in Bié province through participatory observation, semi-structured interviews and transect walks. Ethnobotanical information was quantified based on Use Reports to (1) rate traditional knowledge; and (2) determine most useful taxa. ResultsIn total, 10 traditional healers shared information on their knowledge. A total of 87 plant species distributed among 57 genera and 36 botanical families were documented with Fabaceae being the best-represented family with 18 species, followed by Phyllanthaceae (6), Apocynaceae (5), Asteraceae (5), Rubiaceae (5), Lamiaceae (4), and Ochnaceae (3). Most medicinal plants are usually gathered at a distance from human settlements because of the belief in the higher efficacy of ‘wild’ plants shared by all herbalists. Roots are the most common plant part used (79%), explaining why the consulted herbalists call themselves ‘root doctors’. ConclusionsThe culturally most important medicinal species identified in this study, i.e. Securidaca longepedunculata, Garcinia huillensis, Annona stenophylla, Afzelia quanzensis and Strychnos cocculoides, were previously reported for the same use in neighbouring countries and elsewhere in Africa. Our study also indicates that there are several locally valuable species that have not yet been studied for their medical potential, to name a few: Alvesia rosmarinifolia, Diplorhynchus condylocarpon, Eriosema affine, Paropsia brazzaeana, Rhus squalida, Sclerocroton cornutus or Xylopia tomentosa. Moreover, the ethnomedicinal use of 26 species was reported for the first time to sub-Saharan Africa. ClassificationEthnopharmacological field studies.

Authority of Second-Tier Governments to Reduce Deforestation in 30 Tropical Countries

The authority of state- and province-level governments (“second-tier governments”) to make decisions related to slowing deforestation independently of national governments varies widely across countries. Here we systematically catalog whether second-tier governments in 30 tropical countries with high projected future emissions from deforestation possess 14 distinct types of general and forest-related authority. We compile this information in a free, open-access database. Second-tier governments have broadest authority to reduce deforestation in India, Brazil, Indonesia, Malaysia, Papua New Guinea, Peru, China, Laos, Mozambique, and Vietnam. Second-tier governments have the least authority in Central African Republic, Gabon, Angola, Madagascar, Bolivia, Cambodia, Cameroon, Guyana, Suriname, Thailand, and Venezuela. Second-tier governments have intermediate authority in Democratic Republic of Congo, Ecuador, Mexico, the Philippines, Colombia, Myanmar, Tanzania, Zambia, Mexico, and Republic of Congo. Authorities that second-tier governments most commonly possess include development planning, taxation, budgeting, and roads. Authorities that second-tier governments least commonly possess include land ownership, police, permits for mining, Indigenous affairs, and protected areas. Authorities possessed by an intermediate number of second-tier governments include spatial planning, elections, courts, and permits for agriculture. More than one-quarter of future emissions from deforestation between 2020-2050 is projected to come from just seven out of 678 second-tier jurisdictions: Amazonas, Pará, and Mato Grosso (Brazil), Équateur and Orientale (Democratic Republic of Congo), Loreto (Peru), and El Beni (Bolivia). After weighting for authority, our list of the 50 second-tier jurisdictions in the tropics that are the highest priority for reducing emissions from deforestation shifts to include fewer second-tier jurisdictions in Africa (where second-tier governments have 4.2 authorities out of 14 in the average country) and Latin America (6.3 authorities out of 14) and more second-tier jurisdictions in Asia (8.5 authorities out of 14). Second-tier jurisdictions that have formally expressed interest in reducing emissions from deforestation, e.g. through the Governors’ Climate and Forest Task Force, Under2 Coalition, or New York Declaration on Forests, possess greater authority to reduce deforestation on average than other jurisdictions. Information on second-tier governmental authority, when complemented with deeper country-specific knowledge, can help initiatives for reducing emissions from deforestation (REDD+) prioritize support across regions and across sectoral interventions.

Tracing water mass mixing and continental inputs in the southeastern Atlantic Ocean with dissolved neodymium isotopes

In contrast to the vigorous deep ocean circulation system of the north- and southwestern Atlantic Ocean, no systematically sampled datasets of dissolved radiogenic neodymium (Nd) isotope signatures exist to trace water mass mixing and provenance for the more restricted and less well ventilated Angola Basin and the Cape Basin in the southeastern Atlantic Ocean, where important parts of the return flow of the Atlantic Meridional Overturning Circulation are generated. Here, to improve our understanding of water mass mixing and provenance, we present the first full water column Nd isotope (expressed as εNd values) and concentration data for a section across the western Angola Basin from 3° to 30° S along the Zero Meridian and along an E-W section across the northern Cape Basin at 30° S sampled during GEOTRACES cruise GA08. Compared with the southwestern Atlantic basin we find overall less radiogenic εNd signatures reaching −17.6 in the uppermost 200 m of the Angola and Cape basins. In the western Angola Basin these signatures are the consequence of the admixture of a coastal plume originating near 13° S and carrying an unradiogenic Nd signal that likely resulted from the dissolution of Fe-Mn coatings of particles formed in river estuaries or near the West African coast. The highly unradiogenic Nd isotope signatures in the upper water column of the northern Cape Basin, in contrast, originate from old Archean terrains of southern Africa and are introduced into the Mozambique Channel via rivers like the Limpopo and Zambezi. These signatures allow tracing the advection of shallow waters via the Agulhas and Benguela currents into the southeastern Atlantic Ocean. The Nd isotope compositions of the deep water masses in both basins primarily reflect conservative water mass mixing with the only exception being the central Angola Basin, where the signatures are significantly overprinted by terrestrial inputs. Bottom waters of the Cape Basin show excess Nd concentrations of up to 6 pmol/kg (20%), originating from resuspended bottom sediments and/or dissolution of dust, but without significantly changing the isotopic composition of the waters due to similar εNd values of particles and bottom waters ranging between −9.6 and −10.5. Given that bottom waters within the Cape Basin today are enriched in Nd, non-conservative Nd isotopic effects may have been resolvable under past glacial boundary conditions when bottom waters were more radiogenic.

New collection records for Theraphosidae (Araneae, Mygalomorphae) in Angola, with the description of a remarkable new species of Ceratogyrus

During 2015 and 2016 several baboon spider specimens (Araneae: Theraphosidae) were collected in central Angola during surveys undertaken for the Okavango Wilderness Project. These collections represent range and habitat extensions for Pterinochilus Pocock, 1897, Ceratogyrus Pocock, 1897 and Phoneyusa Karsch, 1884. The new species Ceratogyrusattonitifersp. n. is described from female specimens and the distribution of genera mapped. Central and eastern Angola is severely under sampled for theraphosid spiders, with every species collected during the survey either being potentially new to science or representing a significant range extension for the genus.

Buchholzia coriacea: An African Plant with Pharmacological Importance

Capparidaceae family includes the evergreen shrub Buchholzia coriacea (Wonderful cola), which may be found in Cameroon, Central African Republic, Gabon, Congo, Angola, Nigeria, and Ghana, among other locations. Diarrhea, malaria, rheumatism, ulcers, worm infestation, asthma and cough, diabetes, hypertension, mental disorders, and impotence were among the diseases for which conventional medicine saw it as a viable alternative therapy. Some of its ethnomedicinal knowledge have been ethnopharmacologically validated and published in peer-reviewed journals. As a consequence, the focus of this research is on a current assessment of its confirmed ethnomedicinal activities, which will serve as a research horizon for present and future researchers

Evaluation and projected changes in daily rainfall characteristics over Central Africa based on a multi-model ensemble mean of CMIP5 simulations

This study uses daily rainfall data from 20 global climate models (GCMs) simulations, participating in the phase 5 of the Coupled Model Intercomparison Project (CMIP5) and eight daily rainfall indices defined by the Expert Team on Climate Change Detection and Indices (ETCCDI), to investigate the changes in extreme weather conditions over Central Africa under the representative concentration pathway 8.5. The performance of the multi-model ensemble (MME) mean which in fact refers to the best performing models selected through the Taylor diagram analysis was evaluated by comparing with two gridded daily observation datasets during the historical period (1998–2005). Results show that although some uncertainties may exist between the gridded observation datasets, MME consistently outperform individual models and reasonably reproduced the observed pattern of daily rainfall indices over the region, except in the case of consecutive wet day (CWD) where the high variability of individual members has resulted in the degradation of the overall skill of the MME. The assessment of the climate change signal in the eight daily rainfall indices was done for the mid and late twenty-first century (2026–2056 and 2066–2095 respectively), relative to the baseline historical time period (1976–2005). We found a significant increase in the total wet day rainfall amount (PRCPTOT) over southern (northern) Central Africa from December to February (from September to November). This is mainly due to the increase of high intense rainfall events rather than their frequency. The results also reveal that the increase in PRCPTOT was coupled with increase in the maximum consecutive 5-day rainfall amount (RX5DAY), the 95th percentile (R95), and the total wet day rainfall amount above the 95th percentile (R95PTOT), with more robust patterns of change at the late twenty-first century. The increase in extreme rainfall events (RX5DAY, R95, and R95PTOT) is likely to increase flood risks over Cameroon, Central African Republic, Gabon, Congo, Angola, Zambia, and Democratic Republic of Congo. On the other hand, changes in CWD and PRCPTOT are projected to significantly decrease over Angola, Zambia, and Democratic Republic of Congo from September to November. This is due to a substantial increase of zonal moisture divergence fluxes in upper atmospheric layers. The analysis has also shown that areas where CWD and PRCPTOT decreases coincides with those where consecutive dry days (CDD) increase. The decrease in CWD and PRCPTOT coupled with the increase in CDD could worsen drought risk and significantly disrupt priority socio-economic sectors for development such as rain-fed agriculture, hydroelectric power generation, and water resource availability. The results thus underline the importance for decision-makers to seriously consider adaptation and mitigation measures, in order to limit the risks of natural disasters such as severe droughts and floods that Central African countries may suffer in the future.

Tapping into technology and the biodiversity informatics revolution: updated terrestrial mammal list of Angola, with new records from the Okavango Basin

Using various sources, including the Global Biodiversity Information Facility (GBIF), published literature, recent (2015–2017) collections, as well as bat detector and camera trap surveys with opportunistic sightings and live capture in the upper Okavango catchment in central Angola, we present an updated mammal checklist of 275 species from 15 different orders for Angola (including the Cabinda region). Recent surveys (captures and bat detectors) of small mammals from the upper Okavango catchment yielded 46 species (33 species of bats, ten species of rodents and three species of shrews). One bat (Pipistrellusrusticus, rusty pipistrelle); two rodents (Mussetzeri, Setzer’s mouse andZelotomyswoosnami, Woosnam’s broad-faced mouse) and one shrew (Suncusvarilla, lesser dwarf shrew) were captured for the first time, in Angola. While our species lists of bats conformed to predicted totals, terrestrial small mammals were under sampled, with only 13 species recorded by our trapping survey compared to a total of 42 shrew and rodent species expected based on GBIF records for the central Angolan highlands. Seven terrestrial small mammal species (one shrew and six rodents) are endemic to the central and western Angolan highlands but none of these were captured in our survey. The bat detector surveys added three further bat species to the country list:Pipistrellushesperidus,Kerivoulaargentata, andMopsmidas. Camera trap surveys and opportunistic sightings in the upper Okavango catchment in 2016 yielded a total of 35 species of medium-large mammals, from 17 families, although all of these had been reported previously in Angola. GBIF proved to be an excellent source of biodiversity data for Angolan mammals, most importantly for documenting dramatic historical range changes of larger mammals such as the sable (Hippotragusnigerniger), Kirk’s sable (H.nigerkirkii) and the giant sable (H.nigervariani).