Tropical Regions Research Articles

Identification and Characterization of Fungi in Hibiscus sabdariffa (zobo) Drink Produced and Hawked in Eket Metropolis, Nigeria

Zobo drink is an affordable local soft beverage derived from the calyx of Hibiscus sabdariffa, a herbaceous medicinal plant that thrives in tropical regions. The characterization and identification of fungi present in Zobo drinks produced and sold by vendors in Eket, Akwa Ibom State, was the aim of this study. Hawked Zobo drinks packaged in plastic bottles were purchased from ten different hawkers, two each from five locations. The pH values of the samples were determined and the total fungal count. The pour plate technique, using Sabouraud Dextrose Agar (SDA) was used to determine the total fungal count. Macroscopic and microscopic features were used to characterize the isolates obtained from the samples. The microscopic identification was done by preparing a wet mount of isolated colonies and observing under a microscope. The rate of growth, colony colour, colour changes, colour of reverse colonies, odour and texture of surface were observed and compared with previous work done on fungi. Results showed that the pH of the freshly obtained and stored samples was 3.9 and 2.8 respectively. The average number of colonies for samples stored in the refrigerator ranged from 0.54 x 105 to 0.91 x 105 cfu/ml while that of the freshly obtained samples ranged from 1.26 x 105 to 1.64x105 cfu/ml at 10-3 dilution. A total of 43.6% Aspergillus spp., 29.5% Candida spp. 15.4% Penicillium spp. and 11.5% Rhizopus spp. were identified. With increased acidity in the refrigerated samples, the number reduced to 41.2% Aspergillus spp., 27.4% Candida spp. 15.7% Penicillium spp. and 15.7% Rhizopus spp. The fungi species isolated are known to produce mycotoxins with potential immunosuppressive and cytotoxic effect. These microorganisms could have been introduced to the drinks at various stages of production, during transportation, through the ingredients utilized in the manufacturing process, or even during the cultivation of the Hibiscus sabdariffa plant. This issue can be mitigated by implementing effective manufacturing practices throughout the production process.

PENGENALAN STRUKTUR DAN SIFAT FISIK BAHAN PRODUK TANAMAN BAMBU PADA KELOMPOK TANI DESA URENG, KABUPATEN MALUKU TENGAH

Bamboo is a non-timber forest product that is abundant in tropical and subtropical regions of Asia, thriving in areas with high rainfall. In Indonesia, bamboo can be found in lowland to mountainous areas, typically growing in open spaces. In Ureng Village, bamboo has yet to significantly contribute to improving the local community’s welfare. One of the main factors limiting the optimal utilization of bamboo is the lack of knowledge regarding the physical properties and characteristics of bamboo wood, which could be processed into various economically valuable products. This activity aimed to provide education on the structure and properties of bamboo wood to enhance the economic value for the Ureng Village community. The results show that participants were highly enthusiastic about learning the properties and structure of bamboo wood, which can enable them to utilize bamboo as a substitute for timber.

Cryptic Diversity in Scorpaenodes xyris (Jordan & Gilbert 1882) (Scorpaeniformes: Scorpaenidae) Throughout the Tropical Eastern Pacific.

The tropical eastern Pacific (TEP) is a biogeographic region with a substantial set of isolated oceanic islands and mainland shoreline habitat barriers, as well as complex oceanographic dynamics due to major ocean currents, upwelling areas, eddies, and thermal instabilities. These characteristics have shaped spatial patterns of biodiversity between and within species of reef and shore fishes of the region, which has a very high rate of endemism. Scorpaenodes xyris, a small ecologically cryptic reef-dwelling scorpionfish, is widely distributed throughout the TEP, including all the mainland reef areas and all the oceanic islands. This wide distribution and its ecological characteristics make this species a good model to study the evolutionary history of this type of reef fish across the breadth of a tropical biogeographical region. Our evaluation of geographic patterns of genetic (mitochondrial and nuclear) variation shows that S. xyris comprises two highly differentiated clades (A and B), one of which contains four independent evolutionary subunits. Clade A includes four sub-clades: 1. The Cortez mainland Province; 2. The Revillagigedo Islands; 3. Clipperton Atoll; and 4. The Galapagos Islands. Clade B, in contrast, comprises a single unit that includes the Mexican and Panamic mainland provinces, plus Cocos Island. This geographical arrangement largely corresponds to previously indicated regionalization of the TEP. Oceanic distances isolating the islands have produced much of that evolutionary pattern, although oceanographic processes likely have also contributed.

Plant Growth Promoting Microorganisms and Emerging Biotechnological Approaches for Sugarcane Disease Management

Sugarcane (Saccharum officinarum L.) is a highly valuable agricultural crop, cultivated globally in tropical and subtropical regions, primarily for its sugar content. Out of the 110 countries that grow sugarcane, India and Brazil together account for half of the world’s total production. Being an annual crop, it is prone to many diseases. The major diseases that can affect the sugarcane are red rot, wilt, sett rot, grassy shoot and pokkah boeng. Among the diseases Colletotrichum falcatum, Fusarium sacchari, Ceratocystis paradoxa, Candidatus Phytoplasma and Fusarium fujikuroi pathogen leads to more yield loss. Traditional disease management strategies, such as chemical treatments, conventional methods and biological control, offer limited protection throughout the crop cycle and raise concerns regarding environmental impact and sustainability. In recent years, plant growth-promoting microorganisms (PGPMs) have emerged as a promising alternative, offering environmentally friendly solutions to enhance plant health and manage diseases. RNAi has been explored to manage various diseases caused by viruses, fungi, and bacteria. By silencing key pathogenicity genes in the causal organisms, sugarcane mosaic virus (SCMV), smut, and leaf scald. The integration of PGPMs with RNAi emerging biotechnological tools and transcriptomics presents a sustainable approach to disease control, potentially reducing the dependency on chemical pesticides and promoting eco-friendly agricultural practices.

Exploring plant-based dengue therapeutics: from laboratory to clinic.

Dengue virus (DENV) is a mosquito-borne virus that causes dengue fever, a significant public health concern in many tropical and subtropical regions. Dengue is endemic in more than 100 countries, primarily in tropical and subtropical regions of the world. Each year, up to 400 million people get infected with dengue. Approximately 100 million people get sick from infection, and 40,000 die from severe dengue. Unfortunately, dengue vaccine development is also marred with various complicating factors, as the forefront candidate vaccine performed unsatisfactorily. Moreover, the only licensed vaccine (Dengvaxia) for children 9 through 16years of age is available in just a few countries. The treatment difficulties are compounded by the absence of an effective antiviral agent. Exploring plant-based therapeutics for dengue from the laboratory to clinical application involves a multi-stage process, encompassing various scientific disciplines. Individual investigators have screened a wide range of plant extracts or compounds for potential antiviral activity against DENV. In vitro studies help identify candidates that exhibit inhibitory effects on viral replication. Some of the most promising medicinal plants showing in vitro activity against DENV include Andrographis paniculate, Acorus calamus, and Cladogynos orientalis. Further laboratory studies, both in vitro and in animal models (in vivo), elucidate the mechanisms of action by which the identified compounds exert antiviral effects. Medicinal plants such as Carica papaya, Cissampelos pareira, and Ipomea batata exhibited potent platelet-enhancing activities while Azadirachta indica and Curcuma longa showed promising effects in both in vitro and in vivo studies. Based on positive preclinical results, researchers design clinical trials. This involves careful planning of trial phases, patient recruitment criteria, ethical considerations, and endpoints. The most important medicinal plants showing efficacy and safety in clinical trials include Carica papaya and Cissampelos pareira. This review suggests that several promising medicinal plants exist that have the potential to be turned into clinical drugs to treat dengue infection. However, in addition to developing synthetic and plant-based therapies against dengue infection, vector management strategies should be made robust, emphasizing the need to focus on reducing disease incidence.

Evolution and Drivers of Extreme Subsurface Marine Heatwaves in the Western Tropical Pacific Ocean during 2008 and 2010–11

Abstract Marine heatwaves (MHWs) have adverse impacts on marine ecosystems and fisheries, yet extreme MHWs in the western tropical Pacific Ocean remain largely unexplored. Here, we investigate the evolution and drivers of the two strongest subsurface MHWs in the western tropical Pacific Ocean on record, in 2008 (MHW-08) and 2010–11 (MHW-11). The two events have similar evolutions, as they were both initiated and developed locally in tropical regions during their onset phase and gradually dissipated with multiple cores during the decay phase. We examined the physical processes during the evolution of MHW-08 and MHW-11 and performed a heat budget analysis for the subsurface layer in each case. We find that the onset of both events were mainly controlled by convergence and vertical heat advection due to anomalous Ekman downwelling, while the decay of both events was mainly controlled by horizontal heat advection due to anomalous horizontal currents and withdrawal of anomalous convergence. The relationship between the subsurface MHWs and El Niño–Southern Oscillation is discussed. We suggest that the anomalous heat advections plus the La Niña–related background warming lead to the extreme subsurface MHW events. Our findings may have important implications for environmental change and marine life in the western tropical Pacific Ocean.

Harnessing genomic technologies for one health solutions in the tropics.

The targeted application of cutting-edge high-throughput molecular data technologies provides an enormous opportunity to address key health, economic and environmental issues in the tropics within the One Health framework. The Earth's tropical regions are projected to contain > 50% of the world's population by 2050 coupled with 80% of its biodiversity however these regions are relatively less developed economically, with agricultural productivity substantially lower than temperate zones, a large percentage of its population having limited health care options and much of its biodiversity understudied and undescribed. The generation of high-throughput molecular data and bespoke bioinformatics capability to address these unique challenges offers an enormous opportunity for people living in the tropics. MAIN: In this review we discuss in depth solutions to challenges to populations living in tropical zones across three critical One Health areas: human health, biodiversity and food production. This review will examine how some of the challenges in the tropics can be addressed through the targeted application of advanced omics and bioinformatics and will discuss how local populations can embrace these technologies through strategic outreach and education ensuring the benefits of the One Health approach is fully realised through local engagement. Within the context of the One Health framework, we will demonstrate how genomic technologies can be utilised to improve the overall quality of life for half the world's population.

Projections of future bioclimatic indicators using bias-corrected CMIP6 models: a case study in a tropical monsoon region.

This study evaluates the potential impacts of climate change on Bangladesh by analyzing 19 bioclimatic indicators based on temperature and precipitation. Data from 18 bias-corrected CMIP6 global climate models (GCMs) were used, covering four Shared Socioeconomic Pathways (SSPs)-SSP126, SSP245, SSP370, and SSP585-across three future timeframes: near-term (2015-2044), mid-term (2045-2074), and long-term (2075-2100). Under the high-emission SSP585 scenario, average temperatures are projected to rise by up to 3.76°C, and annual precipitation could increase by 52.6%, reaching up to 3446.38mm by the end of the century. The maximum temperature (Bio5) could reach 32.91°C, while the minimum temperature (Bio6) might rise by 4.43°C, particularly during winter. Precipitation seasonality (Bio15) is projected to increase by as much as 7.9% in the northwest, indicating heightened variability between wet and dry seasons. The diurnal temperature range (Bio2) is expected to decrease by up to - 1.3°C, signifying reduced nighttime cooling, which could exacerbate heat stress. Significant reductions in temperature seasonality (Bio4) are forecast for the northeast, with notable declines in isothermality (Bio3) under SSP585, pointing to increased climatic extremes. These climatic shifts pose severe risks to agricultural productivity, water resource availability, and biodiversity, particularly in flood-prone regions. The findings highlight the need for urgent adaptation measures, including improved flood management systems, efficient water resource use, and climate-resilient agricultural practices. By providing robust region-specific projections, this study offers critical insights for policymakers and stakeholders to mitigate the adverse effects of climate change and safeguard environmental and economic sustainability in Bangladesh.

Evaluation of anemia Haemoprotozoan diseases in goats by using FAMACHA scoring in Barishal district, Bangladesh

Anemia in goats is a prevalent and significant health issue, characterized by pale mucous membranes, tachycardia, weakness, activity intolerance, reduced body weight, and stunted growth. It is often caused by hemoprotozoan diseases, parasitism (both internal and external), and nutritional deficiencies. For small ruminant farmers, anemia poses severe economic challenges by reducing productivity, including slower growth rates and lower milk yields, and increasing mortality if left untreated. This study was conducted in Barishal Sadar Upazila, Barishal district, over a 3 month period from November 2021, to January 2022 Out of 216 goats examined, 37 cases (17.12%) were diagnosed with anemia. The data revealed that Black Bengal goats had the highest prevalence of anemia (62.16%), followed by Jamunapari (29.73%) and crossbreeds (8.11%). Female goats (62.17%) were more affected than males (37.83%). Anemia was most prevalent in goats aged 13-18 months (59.46%), compared to 7-12 months (24.33%) and 0-6 months (16.21%). The FAMACHA scoring system was used to assess anemia severity, offering an affordable, practical, and accessible tool for evaluating conjunctival color on a scale from 1 (no anemia) to 5 (severe anemia). In this study, I standardized the FAMACHA chart for goats in the Barishal district. The results showed that as FAMACHA scores increased, red blood cell (RBC) counts, hemoglobin (Hb) levels, and packed cell volume (PCV) decreased, while white blood cell (WBC) counts increased, indicating more severe anemia. Elevated WBC counts also suggested possible underlying infections. This study underscores the FAMACHA chart’s effectiveness in diagnosing anemia and highlights its potential as a valuable tool for anemia management in tropical and subtropical regions.

Determinants of persistent malaria transmission in the Arjo-Didessa farm area in Ethiopia

Background: In tropical and subtropical areas of the world, malaria is still a serious public health concern. Activities related to agricultural development that involve irrigation schemes likely increase the risk of malaria in tropical and sub-Saharan African regions. Ethiopia is a sub-Saharan country where malaria is endemic.Objectives: The aim of the study was to investigate the determinants related to the persistence of malaria transmission in the Arjo-Didessa sugarcane farm area in southwest Ethiopia.Method: The study employed a quantitative survey design. Quantitative data were collected from 397 households using structured questionnaires. SPSS Statistics version 26 was used to analyse the data. Z- and Chi-square tests were applied, and the data were analysed using logistic regression.Results: The determinants that were identified included variation in land use, water management practices, socioeconomic status and knowledge about the use of anti-malaria treatment. These were shown to contribute to increased malaria transmission and the rise in malaria cases in agricultural areas.Conclusion: The effectiveness of malaria control in agricultural settings can be improved through free access to malaria testing and treatment as well as knowledge about anti-malaria treatment among the residents in agricultural areas.Contribution: The study revealed key determinants, including the promotion of free access to anti-malaria treatment, which should be considered for the effective management of malaria in agricultural areas.

Assessing yellow fever outbreak potential and implications for vaccine strategy.

Yellow fever (YF), a vector-borne viral hemorrhagic fever, is endemic in tropical regions of Africa and South America, with large vaccination programmes being used for control. However, significant outbreaks have occurred in recent years. Data on infection rates and seroprevalence is often sparse, requiring robust mathematical models to estimate the burden of yellow fever. In particular, modelling is required to estimate the risk of outbreaks and inform policy decisions regarding the targeting of vaccination. We present a dynamic, stochastic model of YF transmission which uses environmental covariates to estimate the force of infection due to spillover from the sylvatic (non-human primate) reservoir and the basic reproduction number for human-to-human transmission. We examine the potential for targets identified by the World Health Organization EYE Strategy (50%, 60% or 80% vaccination coverage in 1-60 year olds) to achieve different threshold values for the effective reproduction number. Threshold values are chosen to reflect the potential for seasonal and/or climatic variation in YF transmission even in a scenario where vaccination lowers the median reproduction number below 1. Based on parameter estimates derived from epidemiological data, it is found that the 2022 EYE Strategy target coverage is sufficient to reduce the static averaged annual effective reproduction number R below 1 across most or all regions in Africa depending on the effectiveness of reported vaccinations, but insufficient to reduce it below 0.5 and thereby eliminate outbreaks in areas with high seasonal range. Coverage levels aligned with the 2026 targets are found to significantly decrease the proportion of regions where R is greater than 0.5.

Molecular epidemiology and pathogenicity of Wesselsbron virus circulating in Africa.

Wesselsbron is a neglected, mosquito-borne zoonotic disease transmitted by several species of virus-infected Aedes mosquitoes endemic to tropical regions in Africa. It affects primarily domestic livestock species with teratogenic effects, but can jump to humans. Herein, we investigated the molecular epidemiology of Wesselsbron virus in Africa using whole genome sequencing and structural analysis, and assessed its pathogenicity and tropism through in vivo experiments. A total of twenty-five isolates collected from three countries were successfully characterized. Our study is noteworthy by identifying, for the first time, inter-clade recombination events on the genome of Wesselsbron virus. However, more investigations on the precise molecular mechanisms conducting the occurrence of recombination on the genome of Wesselsbron virus, are warranted. The identification of polymorphisms on motifs of virulence and selection pressures on major proteins showed evidence of genetic evolution for Wesselsbron virus. The clade 1 was more pathogenic and neurotropic in suckling mice and the intramuscular route was found to be the best transmission mode. Our findings also provide new insights in the pathogenicity and tropism of Wesselsbron virus, which could be useful for prevention, preparedness and future outbreak response. Considering its high prevalence in mosquito populations and the increasing number of sporadic human cases, Wesselsbron virus merits more attention in terms of prevention and preparedness, as its mosquito vectors continue to globally expand and there is no vaccine.

Uncovering Below Cloud Rain‐Vapor Interactions During Tropical Rain Events Through Simultaneous and Continuous Real‐Time Monitoring of Rain and Vapor Isotopes

AbstractDue to limited water vapor measurements, vapor isotopes have been traditionally estimated under the assumption of isotopic equilibrium between rain and vapor below cloud base. However, recent advancements in analytical instruments allow more vapor isotopic measurements that have challenged this assumption. To enhance our understanding of rain‐vapor interactions below cloud base in tropical regions, we established an automated system to measure rain and vapor isotopes simultaneously and continuously in real time at minute intervals in Singapore. Among 324 rain events monitored from 2016 to 2019, 81% exhibited a substantial departure of rain and vapor isotopes from the expected equilibrium. This departure suggests that raindrop evaporation plays a larger role in determining their isotopes. The conclusion is supported by the generally lower slopes of the local meteoric water line. Seasonal variations in rain event characteristics indicate changing influences of rain‐vapor interactions: during monsoons, more frequent heavy rainfall maintains relatively high humidity below cloud base, favoring rain‐vapor isotopic equilibrium, whereas during inter‐monsoons, more light rain events lead to pronounced rain evaporation and larger isotopic differences. Furthermore, rain‐vapor interactions below cloud base significantly modulated their isotope evolution during individual events. As events progressed, reduced humidity favored evaporation, increasing rain isotope values and decreasing its d‐excess, whereas vapor isotope values decreased and its d‐excess increased. Our study introduces a new approach to capturing real‐time high‐resolution rain and vapor isotopes at minute intervals to understand the dynamics of rain‐vapor interactions below cloud base. Findings underscore the crucial role of these interactions in influencing rain and vapor isotopes during tropical rain events.

Understanding the future of dengue in Malaysia: Assessing knowledge, attitude, and homeowner practices in mitigating climate-driven risks

Introduction Dengue fever poses a significant public health threat, particularly in tropical regions like Malaysia. The rising incidence of dengue outbreaks challenges healthcare systems and highlights the urgent need for effective preventive measures. Climate change, with rising temperatures and shifting rainfall patterns, is expected to worsen the dengue situation in the coming years. Methods . This is a cross-sectional study conducted among adult residents of low-cost housing apartments in an urban poor community in Kuala Lumpur, Malaysia involving approximately 16,000 residents. A representative sample of 1,636 residents was calculated using the Krejcie and Morgan formula, and stratified random sampling was used to ensure proportional representation across the various floors of each PPR community apartment block. Data were collected using a structured questionnaire adapted from a validated Malay version. The questionnaire assessed respondents’ knowledge, attitudes, and practices (KAP) related to dengue prevention, categorising KAP scores as “Good” (≥80%) or “Poor” (<80%). Descriptive statistics summarized population characteristics and KAP scores, while logistic regression identified predictors of KAP levels, with significance set at p ≤ 0.05. Results In this community, 76.7% of participants exhibited poor knowledge and 83.1% had a negative attitude towards dengue, despite 66.7% demonstrating good preventive practices. The PPR location significantly predicts dengue knowledge, attitudes, and preventive practices, with p-values of less than 0.001 for all domains. Marital status also predicts dengue knowledge (p = 0.007) and preventive practices (p = 0.023), while prior infection with dengue is a predictor of preventive practices (p = 0.047). Conclusion Despite the community’s good dengue prevention practices, likely influenced by environmental expectations, there remains a critical need for education to sustain and strengthen these efforts, as climate change continues to worsen in the coming years. It is crucial to help residents grasp the relevance of these practices, so they can apply them more effectively as climate-driven risks intensify. Targeted interventions should de designed differently for each of the four PPR communities as their levels of knowledge, attitude and practices vary significantly, taking into account independent factors like marital status and prior dengue infection, which shape preventive behaviors.

A-PoRM SIPLAS: Assessing The Post-Disaster Recovery Of Mangrove Forest In Siargao Island Protected Landscape And Seascape (SIPLAS) Area Using Sentinel-1 SAR Data

Abstract. Tropical cyclones and typhoons pose significant threats to coastal ecosystems, particularly mangrove forests. Assessing the extent of mangrove damage and monitoring recovery post-disaster is vital for effective conservation and management strategies. Space-based observations have become increasingly common in monitoring forest damage in tropical regions. However, the predominant methods for change detection rely on satellite optical imagery, which faces challenges in humid tropical zones. Technological advancements have led to the development of detection techniques utilizing synthetic aperture radar (SAR) to address cloud cover issues. The study specifically targets Siargao Island Protected Landscape and Seascape (SIPLAS), the largest contiguous forest in the Philippines, from destruction caused by Super typhoon Rai (Odette). The study utilized SAR time-series data, unsupervised log ratio change detection method and Cumulative Sum (CuSum) analysis via Google Earth Engine (GEE). Analysis of Sentinel-1 GRD images found VV polarization had the highest accuracy at 92% and an F-measure of 0.92. VH polarization had 87.5% accuracy and an F-measure of 0.87, while combining VV and VH and VV/VH achieved the same results of 80.5% overall accuracy with an F-measure of 0.82. With that, results indicated that 53% of mangroves in SIPLAS area were damaged, with 38.05% regenerating by 2022 and 56.75% by 2023, notably after September 16, 2022 detected from CuSum analysis using the VV polarization. These findings substantiate the robustness of the data and methodologies employed in monitoring mangrove resilience and supporting conservation initiatives within the SIPLAS area.

Enhancing Okra Growth and Yield Through Foliar Nutrient Application in Conjunction with Mulching and Drip Irrigation

Background: Okra (Abelmoschus esculentus) is an important vegetable crop that belongs to family malvaceae and is grown both in tropical and subtropical regions of India. In north-coastal Andhra Pradesh, okra is cultivated frequently so, optimizing the nutrient management practice is an efficient method for increasing yield. Among those practices, foliar fertilizers, mulching and irrigation methods are essential in maximizing the yield and quality of okra. Therefore, the present investigation deals with the combined effects of foliar nutrients, mulching and irrigation methods, providing valuable data for sustainable okra production in a particular area. Methods: The present investigation was conducted during June to September 2023, with seven different treatments using randomized block design. This experiment mainly focuses on combinations of mulching and foliar sprays of 19:19:19 and 13:0:45 at different concentrations. Collected data were analyzed using ANOVA and fisher’s least significant difference test at a 5% significance level. Result: Among all the treatments, 100% RDF along with the foliar application of 19:19:19 @ 1.0% + 13:0:45 @ 2% at 30, 45 and 60 days after sowing has proven the best treatment, where it recorded the highest yield of 101 q per hectare (Q/ha) due to the application of sufficient nutrients. Whereas, the lowest yield was recorded with control plot due to insufficient nutrient supply in relation to growth and yield parameters.

Overview of Brinjal (Solanum melongena L.) Pests and Their Management: A Review

Brinjal (eggplant or aubergine), a widely cultivated vegetable in tropical and subtropical regions, faces significant threats from a variety of insect pests. These pests cause substantial damage at different stages of crop growth, leading to reduced yields and compromised fruit quality. This review provides a comprehensive overview on the major insect pests that affect brinjal cultivation, focusing on their biology, damage mechanisms, and current management practices. Special emphasis is placed on integrated pest management (IPM) strategies, combining cultural, biological and chemical control methods to promote sustainable brinjal production.

Killer whales in the Gulf of Mexico and North Atlantic off the Southeastern United States

Killer whales occur in the Gulf of Mexico (GoMex) and the North Atlantic, including off the southeastern United States (SEUS). Data from cetacean surveys during 1990 – 2021 and other sources were combined to assess killer whale biology, including spatial and temporal distribution, social structure, genetics, morphology, acoustics, and predatory behavior. GoMex records occurred predominantly in oceanic waters (>200 m) during spring and summer. SEUS records occurred primarily in winter and spring off the North Carolina region along the shelf-edge and deeper waters, and off the east coast of Florida. Photo-identification analysis of GoMex killer whales resulted in 49 individuals sighted up to seven times with sighting histories up to 26 years, and social analysis provided evidence of long-term relationships up to 16 years. The GoMex genetic samples revealed two mtDNA haplotypes, one of which does not match any outside the GoMex. Most GoMex whales had wide non-faint saddle patches and many had cookiecutter shark scars while no scars were noted on SEUS whales. Three groups recorded in the GoMex made few calls, but a group harassing sperm whales produced many. Cetaceans and tuna are known prey in the GoMex and SEUS, respectively. Directed studies of killer whales in the GoMex areas would be difficult to implement as this species is very rare. It is therefore important to pursue ongoing efforts to collect behavioral, acoustic and any biological samples that will contribute to improve our understanding of the biology and ecology of killer whales in tropical and subtropical regions.

Genotypic and phylogeographic insights into a pre-epidemic variant of Wesselsbron virus detected in sylvatic Aedes mcintoshi from Semuliki Forest, Uganda.

Wesselsbron virus (WSLV) is a neglected mosquito-borne virus within the yellow fever subgroup in the genus Orthoflavivirus of the Flaviviridae family. Despite being primarily a veterinary pathogen able to cause stillbirths, congenital malformations, and mortality in ruminants, WSLV also infects humans, causing a usually self-limiting febrile illness, or may lead to neurological complications in rare cases. WSLV causes sporadic outbreaks in Southern Africa, but findings in mosquitoes from other African countries suggest a wider distribution. Here, we report the detection and isolation of WSLV from an Aedes mcintoshi mosquito collected in a pristine ecosystem within Semuliki National Park, western Uganda. The detected strain M5937-UG-2018 was impaired in infectivity, replication, and production of infectious particles in cell lines derived from different hosts compared to an epidemic reference strain, SA H177. Full-genome sequencing by next-generation sequencing from the mosquito homogenate revealed a maximum nucleotide identity of 98.1% to a WSLV isolate from a human sample collected in South Africa in 1996. M5937-UG-2018 grouped in phylogenetic analyses with strains from South Africa and Senegal. Reconstruction of the temporal and spatial dispersal of WSLV across Africa estimated a likely origin of WSLV in South Africa in the early 19th century and spread in Southern Africa in the following decades. Long-distance movement toward Western and Eastern Africa was modeled to have occurred in the early 21st century. However, displacing the origin of M5937-UG-2018 did not decrease the likelihood of the model supporting the hypothesis that WSLV is widely distributed in Africa.IMPORTANCEWSLV is a neglected mosquito-borne virus causing teratogenicity in ruminants and febrile illness in humans. WSLV is mainly endemic to Southern Africa, but findings in other regions suggest a wider distribution on the continent. Knowledge of the distribution of WSLV is impaired as differential diagnostics are rarely performed in livestock and humans presenting with symptoms compatible with WSLV infection. Our work investigating viral infections in mosquitoes from a remote tropical rainforest region demonstrates that WSLV is endemic in Uganda. The isolated virus was less infective and showed lower replication ability in vitro compared to an epidemic isolate from South Africa. Phylogeographic reconstruction of spatial and temporal movements, along with the displacement of the origin of the newly detected strain, suggests that WSLV may be widely distributed across Africa. Our data show that the geographic distribution of WSLV and its impact on human and animal health are likely underestimated.

The contribution of tropical long-term studies to mycology.

Fungi are arguably the most diverse eukaryotic kingdom of organisms in terms of number of estimated species, trophic and life history strategies, and their functions in ecosystems. However, our knowledge of fungi is limited due to a distributional bias; the vast majority of available data on fungi have been compiled from non-tropical regions. Far less is known about fungi from tropical regions, with the bulk of these data being temporally limited surveys for fungal species diversity. Long-term studies (LTS), or repeated sampling from the same region over extended periods, are necessary to fully capture the extent of species diversity in a region, but LTS of fungi from tropical regions are almost non-existent. In this paper, we discuss the contributions of LTS of fungi in tropical regions to alpha diversity, ecological and functional diversity, biogeography, hypothesis testing, and conservation-with an emphasis on an ongoing tropical LTS in the Pakaraima Mountains of Guyana. We show how these contributions refine our understanding of Fungi. We also show that public data repositories such as NCBI, IUCN, and iNaturalist contain less information on tropical fungi compared to non-tropical fungi, and that these discrepancies are more pronounced in fungi than in plants and animals.