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African pangolins are intensively harvested to feed illegal trade networks. We focused on the conservation genetics of the most trafficked African species, the white-bellied pangolin (WBP;Phataginus tricuspis), through the genotyping of 562 individuals from reference populations and urban bushmeat markets in a vibrant trade hub from western Central Africa. Across Cameroon, Equatorial Guinea and northern Gabon, we observed a lack of genetic differentiation and a signature of isolation-by-distance possibly due to unsuspected dispersal capacities involving a Wahlund effect. Despite a higher level of genetic diversity compared to western Africa, we detected a 74-83% decline in the effective population size of WBP during the Middle Holocene. Private allele frequency tracing approach indicated up to 600 km sourcing distance by large urban markets from Cameroon, involving transnational trade activities. The 20 microsatellites markers used in this study provided the necessary power to distinguish among all WBP individuals and should be considered a valuable resource for future forensic applications. Because lineage admixture was detected in the study area, we recommend a multi- locus approach for tracing the WBP trade. The Yaoundé market was a major recruiter of genetic diversity in the region, and should receive urgent conservation action to mitigate the pangolin trade.

Sex chromosomes are typically comprised of a non-recombining region and a recombining pseudoautosomal region. Accurately quantifying the relative size of these regions is critical for sex chromosome biology both from a functional (i.e. number of sex-linked genes) and evolutionary perspective (i.e. extent of Y degeneration and X-Y heteromorphy). The evolution of the pseudoautosomal boundary (PAB) - the limit between the recombining and the non-recombining regions of the sex chromosomes - is well documented in haplorrhines (apes and monkeys) but not in strepsirrhines (lemurs and lorises), which represent almost 30% of all primates. Here we studied the PAB of seven species representing the main strepsirrhine lineages by sequencing a male and a female genome in each species and using sex differences in coverage to identify the PAB. We found that during primate evolution, the PAB has remained unchanged in strepsirrhines whereas several recombination suppression events moved the PAB and shortened the pseudoautosomal region in haplorrhines. Strepsirrhines are well known to have much lower sexual dimorphism than haplorrhines. We suggest that mutations with antagonistic effects between males and females have driven recombination suppression and PAB evolution in haplorrhines. Our work supports the view that sexually antagonistic mutations have influenced the evolution of sex chromosomes in primates.