Knowledge on faunal diversification in African rainforests remains scarce. We used phylogeography to assess (i) the role of Pleistocene climatic oscillations in the diversification of the African common pangolin (Manis tricuspis) and (ii) the utility of our multilocus approach for taxonomic delineation and trade tracing of this heavily poached species. We sequenced 101 individuals for two mitochondrial DNA (mtDNA), two nuclear DNA and one Y-borne gene fragments (totalizing 2602 bp). We used a time-calibrated, Bayesian inference phylogenetic framework and conducted character-based, genetic and phylogenetic delineation of species hypotheses within African common pangolins. We identified six geographic lineages partitioned into western Africa, Ghana, the Dahomey Gap, western central Africa, Gabon and central Africa, all diverging during the Middle to Late Pleistocene. MtDNA (cytochrome b + control region) was the sole locus to provide diagnostic characters for each of the six lineages. Tree-based Bayesian delimitation methods using single- and multilocus approaches gave high support for 'species' level recognition of the six African common pangolin lineages. Although the diversification of African common pangolins occurred during Pleistocene cyclical glaciations, causative correlation with traditional rainforest refugia and riverine barriers in Africa was not straightforward. We conclude on the existence of six cryptic lineages within African common pangolins, which might be of major relevance for future conservation strategies. The high discriminative power of the mtDNA markers used in this study should allow an efficient molecular tracing of the regional origin of African common pangolin seizures.

Background African pangolins are currently experiencing unprecedented levels of harvesting, feeding both local demands and the illegal international trade. So far, the lack of knowledge on the population genetics of African pangolins has hampered any attempts at assessing their demographic status and tracing their trade at the local scale. We conducted a pioneer study on the genetic tracing of the African pangolin trade in the Dahomey Gap (DG). We sequenced and genotyped 189 white-bellied pangolins from 18 forests and 12 wildlife markets using one mitochondrial fragment and 20 microsatellite loci. Results Tree-based assignment procedure showed that the pangolin trade is endemic to the DG region, as it was strictly fed by the the Dahomey Gap lineage (DGL). DGL populations were characterized by low levels of genetic diversity, an overall absence of equilibrium, important inbreeding levels, and lack of geographic structure. We identified a 92–98% decline in DGL effective population size 200–500 ya—concomitant with major political transformations along the ‘Slave Coast’—leading to contemporaneous estimates being inferior to minimum viable population size (< 500). Genetic tracing suggested that wildlife markets from the DG sourced pangolins through the entire DGL range. Our loci provided the necessary power to distinguish among all the genotyped pangolins, tracing the dispatch of a same individual on the markets and within local communities. We developed an approach combining rarefaction analysis of private allele frequencies with cross-validation of observed data that traced five traded pangolins to their forest origin, c. 200–300 km away from the markets. Conclusions Although the genetic toolkit that we designed from traditional markers can prove helpful to trace the illegal trade in pangolins, our tracing ability was limited by the lack of population structure within the DGL. Given the deleterious combination of genetic, demographic, and trade-related factors affecting DGL populations, the conservation status of white-bellied pangolins in the DG should be urgently re-evaluated.

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Heavy metal pollution in aquatic ecosystems is one of the most important threats of human health and food chain. Thus, in this study, the level of Cd, Fe, Hg, Mn, Pb and Zn accumulation in surface sediments and in Galatea paradoxa, were investigated to estimate their potential health risks via consumption to residents alongside the Mono river, Togo-Benin border. Samples were collected at two fishing areas and analyzed using flame atomic absorption spectrophotometry Moreover, the likely health risks developed as a result of human contamination by heavy metal through clam consumption was also assessed using target hazard quotient (THQ) and hazard index (HI). The mean maximal metal concentrations (μg/g dw) were as follows: Fe (25624) > Mn (1176.0) > Zn (23.29) > Pb (4.67) > Hg (0.038) in silty sediments and Fe (15692) > Mn (654.78) > Zn (12.53) > Pb (2.42) > Hg (0.034) in sandy sediments. Cd content were all below the detectable limit. When compared against some consensus-based sediment quality guidelines (TEL, ERL, AFNOR), it was observed that all the concentrations, excluding Fe levels in the samples, were lower than reference values. Similarly, computed PLI was less than 1 indicating that the lower tidal parts of the Mono were unpolluted. The accumulation pattern of studied trace metals in the clams followed a slightly different trend from that found in the sediments (Fe>Zn>Mn>Hg>Pb>Cd). Fe (1353 ± 162 μg/g dw) and Zn (51,8 ± 8.9 μg/g dw) content in whole tissues of G. paradoxa were well above the maximum concentration allowable by food safety criteria. In contrast, Cd (0.097 mg/kg dw), Hg (0.24 mg/kg dw) and Pb (0.18 mg/kg dw) content were very low. Computed THQ values were all below 1, with highest results found in the small size clams regardless of the heavy metals. The HI values indicate that none of the analyzed heavy metals may pose serious risk to consumers through the clams studied. The highest risk was posed by small clams, followed in decreasing order by medium and large clams. We therefore suggest that the clams taken from main fishing locations at Mono river are safe to eat.