Where are you from, stranger? The enigmatic biogeography of North African pond turtles (Emys orbicularis) .

Abstract The European pond turtle (Emys orbicularis) is aNearctic element in the African fauna and thought to haveinvaded North Africa from the Iberian Peninsula. All NorthAfrican populations are currently identified with the subspeciesE. o. occidentalis. However, a nearly range-wide sampling inNorth Africa used for analyses of mitochondrial and microsatelliteDNA provides evidence that only Moroccan populationsbelong to this taxon, while eastern Algerian and Tunisian pondturtles represent an undescribed distinct subspecies. These twotaxa are most closely related to E. o. galloitalica with a nativedistribution along the Mediterranean coast of northern Spainthrough southern France to western and southern Italy. Thisgroup is sister to a clade comprising several mitochondrial lineagesand subspecies of E. orbicularis from Central and EasternEurope plus Asia, and the successive sisters are E. o. hellenicaand E. trinacris. Our results suggest that E. orbicularis has beenpresent in North Africa longer than on the Iberian Peninsula andthat after an initial invasion of North Africa by pond turtles froman unknown European source region, there was a phase ofdiversification in North Africa, followed by a later re-invasionof Europe by one of the African lineages. The differentiation ofpond turtles in North Africa parallels a general phylogeographicparadigm in amphibians and reptiles, with deeply divergentlineages in the western and eastern Maghreb. Acknowledgingtheir genetic similarity, we propose to synonymize the previouslyrecognized Iberian subspecies E. o. fritzjuergenobsti with E. o.occidentalis sensu stricto. The seriously imperiled Moroccanpopulations of E. o. occidentalis represent two ManagementUnits different in mitochondrial haplotypes and microsatellitemarkers. The conservation status of eastern Algerian pond turtlesis unclear, while Tunisian populations are endangered.Considering that Algerian and Tunisian pond turtles representan endemic taxon, their situation throughout the historical rangeshould be surveyed to establish a basis for conservationmeasures.