Phylogeography of the heavily poached African common pangolin (Pholidota, Manis tricuspis ) reveals six cryptic lineages as traceable signatures of Pleistocene diversification
Résumé
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 characterbased,
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. Treebased
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.