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Simple Summary: The French Polynesian islands represent a unique insular system in the Pacific Ocean. Previous surveys of the marine flora of French Polynesia were mostly established on traditional morphology-based taxonomy. DNA barcoding allowed us to provide a major revision of French Polynesian marine flora, with an updated total of 702 species from French Polynesia, including 119 species of Chlorophyta, 169 Cyanobacteria, 92 Ochrophyta, 320 Rhodophyta, and 2 species of sea-grasses (Alismatales)-nearly a two-fold increase from previous estimates. In addition to improving and refining our knowledge of French Polynesian marine flora, this study also provides a valuable DNA barcode reference library for identification purposes and future taxonomic and conservation studies. A significant part of the diversity uncovered corresponds to unidentified lineages, which will need careful taxonomic examination. Located in the heart of the South Pacific Ocean, the French Polynesian islands represent a remarkable setting for biological colonization and diversification, because of their isolation. Our knowledge of this region's biodiversity is nevertheless still incomplete for many groups of organisms. In the late 1990s and 2000s, a series of publications provided the first checklists of French Polynesian marine algae, including the Chlorophyta, Rhodophyta, Ochrophyta, and Cyanobacteria, established mostly on traditional morphology-based taxonomy. We initiated a project to systematically DNA barcode the marine flora of French Polynesia. Based on a large collection of similar to 2452 specimens, made between 2014 and 2023, across the five French Polynesian archipelagos, we re-assessed the marine floral species diversity (Alismatales, Cyanobacteria, Rhodophyta, Ochrophyta, Chlorophyta) using DNA barcoding in concert with morphology-based classification. We provide here a major revision of French Polynesian marine flora, with an updated listing of 702 species including 119 Chlorophyta, 169 Cyanobacteria, 92 Ochrophyta, 320 Rhodophyta, and 2 seagrass species-nearly a two-fold increase from previous estimates. This study significantly improves our knowledge of French Polynesian marine diversity and provides a valuable DNA barcode reference library for identification purposes and future taxonomic and conservation studies. A significant part of the diversity uncovered from French Polynesia corresponds to unidentified lineages, which will require careful future taxonomic investigation.

Fish as a foodstuff of high nutritional value is considerably perishable. It must be transformed in order to improve the duration of its conservation. Drying and smoking are the most popular processes to transform fish in northern Cameroon. These steps usually affect the quality of the finished products. In order to improve the quality of locally transformed fish in a handmade manner and to typify such activity, an survey was conducted in three fishing ponds in the Northern part of Cameroon with 160 fishermen and fish transformers. It appears that the technique of transforming fish in those main fishing ponds in Northern Cameroon vary at the level of preprocessing and dehydration phases of fresh fish. Smoking is done in a traditional oven followed by cleaning (4.1% in the Adamawa Region and 33.0% in the North and Far North Region) or flaking of the fish (95.9% in Adamawa and 61.1% in the North and the Far North Region). Then, come emptying (95.9% in Adamawa and 61.1% in the North and Far North), cutting into small pieces (11.1% in the Far North) or cracking (82.6% in the Adamawa Region). At the end, washing (95.9% in the Adamawa and 72.2% in the North and Far North), spinning (100%), smoking (100%) and then packaging of the fish (100%) complete the process. All these operations are conducted without equipment for protection, on uncleaned surfaces and with irregularly washed materials with clean water. The drying process is done on bare ground on top of a drying stall is a constant step in the Far North (54.9%) and North (28.6%) regions and scarce in the Adamawa region (9.3%). A particular emphasis should be laid on hygienic measures to ensure a sanitary quality of dry fish at the end of both smoking and drying processes.

AbstractBackgroundThailand has made substantial progress toward malaria elimination, with 46 of the country’s 77 provinces declared malaria free as part of the subnational verification program. Nonetheless, these areas remain vulnerable to the reintroduction of malaria parasites and the reestablishment of indigenous transmission. As such, prevention of reestablishment (POR) planning is of increasing concern to ensure timely response to increasing cases. A thorough understanding of both risk of parasite importation and receptivity for transmission is essential for successful POR planning.MethodsRoutine geolocated case- and foci-level epidemiological and case-level demographic data were extracted from Thailand’s national malaria information system for all active foci from October 2012 to September 2020. A spatial analysis examined environmental and climate factors associated with remaining active foci. A logistic regression model collated surveillance data with remote sensing data to investigate associations with the probability of having reported an indigenous case within the previous year.ResultsActive foci are highly concentrated along international borders, particularly Thailand’s western border with Myanmar. Although there is heterogeneity in the habitats surrounding active foci, land covered by tropical forest and plantation was significantly higher for active foci than other foci. The regression results showed that tropical forest, plantations, forest disturbance, distance from international borders, historical foci classification, percentage of males, and percentage of short-term residents were associated with high probability to report indigenous cases.ConclusionThese results confirm that Thailand’s emphasis on border areas and forest-going populations is well placed. The results suggest that environmental factors alone are not driving malaria transmission in Thailand; rather, other factors, including demographics and behaviors, may also be contributors. However, these factors are syndemic, so human activities in areas covered by tropical forests and plantations may result in malaria importation and potentially, local transmission, in foci that previously had been cleared. These factors should be addressed in POR planning.

Protecting existing mangrove forests is a priority for global conservation because of the wide range of services that these coastal forests provide to humankind. Despite the recent reduction in global rates of mangrove loss, high historical loss rates mean that there are at least 800,000 ha globally that are potentially suitable for mangrove re-establishment. Recently deposited mud banks or intertidal, previously terrestrial, land might provide additional habitat for expanding mangrove areas locally. There is a long history of mangrove rehabilitation. However, despite numerous good examples of, and growing expertise in, natural or assisted (re-)establishment activities, most mangrove planting efforts, for instance, either fail entirely or meet with only limited success. Exposed to waves and currents and subject to tidal inundation, mangroves differ from terrestrial forests, and approaches to, or tools for, terrestrial forest restoration cannot easily be transferred to mangrove forests. Successful mangrove (re-)establishment usually requires a robust understanding of the abiotic and biotic conditions of the chosen site, the ecological requirements of the mangrove species used or facilitated, the reasons for previous mangrove loss or degradation, as well as the barriers–both societal and ecological–that have prevented natural recovery to date. Because most mangrove forests are socio-ecological systems, with which local human populations are intimately engaged, (re-)establishment will normally require the support of, and engagement with, local communities and other local stakeholders. Here, we summarize where, when and why (re-)establishment of mangroves is needed and how to assess this need. We discuss a range of potential aims and goals of mangrove (re-)establishment along with potential pitfalls along the way from conceiving the initial idea to its realization. We compare different technical and conceptual approaches to mangrove (re-)establishment, their challenges and opportunities, and their design and financial requirements, as well as potential solutions. We ground our final outlook and recommendations on examples of successful efforts and the factors that rendered (re-)establishment successful in the past.

Examination of some Teleost fish caught in the Maga Lake located in the Far North Region of Cameroon, revealed the presence of two new species of Myxosporidia belonging to the genus Myxobolus, of which morphological and histological description is given in the present study. These species are: Myxobolus kodjii sp. nov., parasite of the eyes of Labeo senegalensis and Myxobolus dzeufieti sp. nov., parasite of the skin of Oreochromis niloticus and Tilapia sp. M. kodjii sp. nov. forms ovoid myxospores, with rounded ends, 8.0 (7.0–9.0) μm long, 5.9 (5.5–6.6) μm wide and 3.8 (3.5–4.2) μm thick. Polar capsules are pyriform, equal in size and measure 3.7 (3.2–4.0) μm × 1.6 (1.4–2.0) μm. M. dzeufieti sp. nov. forms ovoid myxospores, with the anterior end slightly narrowed, 12.3 (11.4–13.7) μm long, 9.8 (9.2–10.6) μm wide and 5.7 (5.0–6.0) μm thick. Its polar capsules are pyriform and equal in size and measure 4.8 (4.0–5.5) μm × 2.9 (2.5–3.3) μm. These new species of Myxobolus are histozoic. The cysts of M. kodjii sp. nov. induce a local inflammatory reaction and their implantation in the sclera can affect the sight of the host fish. The presence of the cysts of M. dzeufieti sp. nov. on the skin did not cause an inflammatory reaction in host fish. 

Abstract Background Hybrids between Schistosoma haematobium (Sh) and S. bovis (Sb) have been found in several African countries as well as in Europe. Since the consequences of this hybridization are still unknown, this study aims to verify the presence of such hybrids in Cameroonian humans, to describe the structure of S. haematobium populations on a large geographic scale, and to examine the impact of these hybrids on genetic diversity and structure of these populations. Methods From January to April 2019, urine from infected children was collected in ten geographically distinct populations. Miracidia were collected from eggs in this urine. To detect the presence of hybrids among these miracidia we genotyped both Cox1 (RD-PCR) and ITS2 gene (PCR-RFLP). Population genetic diversity and structure was assessed by genotyping each miracidium with a panel of 14 microsatellite markers. Gene diversity was measured using both heterozygosity and allelic richness indexes, and genetic structure was analyzed using paired Fst, PCA and Bayesian approaches. Results Of the 1327 miracidia studied, 88.7% were identified as pure genotypes of S. haematobium (Sh_Sh/Sh) while the remaining 11.3% were hybrids (7.0% with Sh_Sh/Sb, 3.7% with Sb_Sb/Sh and 0.4% with Sb_Sh/Sb). No miracidium has been identified as a pure genotype of S. bovis. Allelic richness ranged from 5.55 (Loum population) to 7.73 (Matta-Barrage) and differed significantly between populations. Mean heterozygosity ranged from 53.7% (Loum) to 59% (Matta Barrage) with no significant difference. The overall genetic differentiation inferred either by a principal component analysis or by the Bayesian approach shows a partial structure. Southern populations (Loum and Matta Barrage) were clearly separated from other localities but genetic differentiation between northern localities was limited, certainly due to the geographic proximity between these sites. Conclusions Hybrids between S. haematobium and S. bovis were identified in 11.3% of miracidia that hatched from eggs present in the urine of Cameroonian schoolchildren. The percentages of these hybrids are correlated with the genetic diversity of the parasite, indicating that hybridization increases genetic diversity in our sampling sites. Hybridization is therefore a major biological process that shapes the genetic diversity of S. haematobium. Graphical Abstract

Some volcanic rocks from Nyiragongo volcano in the Democratic Republic of Congo contain highly oxidized olivine crystals. These olivines crystals are made of two phases, dark olivine on backscattered electron images of pure forsterite composition and grey Mg-poor areas made of olivine and iron-rich oxides. Calculation of the initial composition confirms that they are primary olivine with late separation of two different olivine compositions. Pure forsterite is enriched in SiO2 but contains lower amounts of CaO than Fe-rich areas, in agreement with expected partitioning of these elements related to the composition of the olivine. Iron-rich oxides formed around or inside the olivine crystals during the separation process and confirm a highly oxidized environment during their evolution. We propose that this separation occurred during subsolidus recrystallization under high fO2 conditions of the olivine crystals after cooling of the volcanic rocks. It provides evidences for circulation of iron-rich fluids or gas inducing deuteritic processes occurring in the large volcanic cone of the Nyiragongo, in relation with the presence of a shallow magma chamber connected to a large and permanent lava lake