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Studying phylogeographic histories in wide-ranging species provides key insights into those processes shaping current species’ distributions and genetic structuring. In this work, we extend previous sampling and analyse data from three mitochondrial genes to explore in-depth the phylogeography of the spur-thighed tortoise (Testudo graeca), the most widely distributed of Western Palearctic tortoise species. The combination of loci with different evolutionary rates and new fossil data in molecular clock analyses allow us to infer a dual diversification burst of the species, which took place since the Mio-Pliocene for the eastern subspecies and during the Pleistocene for the subspecies distributed in North Africa. The latter seems to correspond to a more or less contemporary diversification burst, which resulted in the current west–east allopatric/parapatric distribution of the North African lineages. In addition to the previously known genetic lineages, a new one was discovered in Libya. Within a more recent framework, we use estimates of genetic diversity and demographic inferences from molecular data to address the origin of three extant Western European populations. The comparison of their current genetic signatures supports the recent introduction of T. graeca into Majorca and Sardinia and an ancient origin of the populations in south-eastern Spain. The fossil history of T. graeca supports our findings from the most comprehensive and unifying phylogeographic study conducted to date for T. graeca. Our work highlights T. graeca as a paradigmatic system for studying phylogeographic processes that act in very different temporal and geographical contexts.

The Magdalena River Turtle (Podocnemis lewyana) is a Colombian endemic species, endangered due to human exploitation and habitat destruction. To date, this species is poorly known ecologically and data on its genetic diversity are lacking. Here we report on the first genetic survey of the species across its distribution range. We obtained mitochondrial DNA sequences (488 bp) of the cytochrome b gene from 109 individuals. Samples belong to populations located at several different localities, grouped in five regions, along the four main river basins: Magdalena, Cauca, San Jorge, and Sinú drainages. We found two haplotypes, which differ in only one nucleotide substitution and which are represented with different frequencies in the five geographic regions. These results suggest that P. lewyana harbors little genetic variation and is a genetically uniform species, but more variable markers (i.e., microsatellites) should be used to unravel fine-scale phylogeographic structures in this species.

The Magdalena River Turtle (Podocnemis lewyana) is a Colombian endemic species, endangered due to human exploitation and habitat destruction. To date, this species is poorly known ecologically and data on its genetic diversity are lacking. Here we report on the first genetic survey of the species across its distribution range. We obtained mitochondrial DNA sequences (488 bp) of the cytochrome b gene from 109 individuals. Samples belong to populations located at several different localities, grouped in five regions, along the four main river basins: Magdalena, Cauca, San Jorge, and Sinú drainages. We found two haplotypes, which differ in only one nucleotide substitution and which are represented with different frequencies in the five geographic regions. These results suggest that P. lewyana harbors little genetic variation and is a genetically uniform species, but more variable markers (i.e., microsatellites) should be used to unravel fine-scale phylogeographic structures in this species.