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The butterfly genus Erebia (Lepidoptera: Nymphalidae) is the most diverse in Europe and comprises boreo-alpine habitat specialists. Populations are typically fragmented, restricted to high altitudes in one or several mountain ranges, where habitat is relatively well preserved, but where the effects of climate change are considerable. As a result, the genus Erebia has become a model to study the impact of climate changes, past and present, on intraspecific genetic diversity. In this study, we inferred phylogenetic relationships among populations of the European species Erebia epiphron and Erebia orientalis using mitochondrial (COI) and nuclear markers (ITS2, wg and RPS5), and reconstructed their phylogeographical history. We confirm E. orientalis and E. epiphron as a relatively young species pair that split c. 1.53 (±0.65) Mya. The high genetic homogeneity of E. orientalis, combined with its restricted geographical range in the eastern Balkans, suggests that this taxon may be subject to inbreeding depression and displays low adaptability to potential environmental changes, which calls for close monitoring of population trends. By contrast, genetic structure was complex for E. epiphron, revealing an intricate phylogeographical history that included a succession of dispersal events, mixing of populations and periods of isolation in multiple refugia. Finally, we highlight southern populations that represent unique genetic lineages, which, in the case of extinction, would lead to important genetic erosion. [ABSTRACT FROM AUTHOR]

Previous studies have shown a dynamic karyotype evolution and the presence of complex sex chromosome systems in three cryptic Leptidea species from the Western Palearctic. To further explore the chromosomal particularities of Leptidea butterflies, we examined the karyotype of an Eastern Palearctic species, Leptidea amurensis. We found a high number of chromosomes that differed between the sexes and slightly varied in females (i.e. 2 n = 118-119 in females and 2 n = 122 in males). The analysis of female meiotic chromosomes revealed multiple sex chromosomes with three W and six Z chromosomes. The curious sex chromosome constitution [i.e. W1-3/Z1-6 (females) and Z1-6/Z1-6 (males)] and the observed heterozygotes for a chromosomal fusion are together responsible for the sex-specific and intraspecific variability in chromosome numbers. However, in contrast to the Western Palearctic Leptidea species, the single chromosomal fusion and static distribution of cytogenetic markers (18S rDNA and H3 histone genes) suggest that the karyotype of L. amurensis is stable. The data obtained for four Leptidea species suggest that the multiple sex chromosome system, although different among species, is a common feature of the genus Leptidea. Furthermore, inter- and intraspecific variations in chromosome numbers and the complex meiotic pairing of these multiple sex chromosomes indicate the role of chromosomal fissions, fusions, and translocations in the karyotype evolution of Leptidea butterflies. [ABSTRACT FROM AUTHOR]

Polyommatus ripartii is a biogeographically and taxonomically poorly understood species of butterfly with a scattered distribution in Europe. Recently, it has been shown that this species includes several European endemic and localized taxa ( galloi, exuberans, agenjoi) that were previously considered species and even protected, a result that poses further questions about the processes that led to its current distribution. We analysed mitochondrial DNA and the morphology of P. ripartii specimens to study the phylogeography of European populations. Three genetically differentiated but apparently synmorphic lineages occur in Europe that could be considered evolutionarily significant units for conservation. Their strongly fragmented and counterintuitive distribution seems to be the result of multiple range expansions and contractions along Pleistocene climatic oscillations. Remarkably, based on the 79 specimens studied, these genetic lineages do not seem to extensively coexist in the distributional mosaic, a phenomenon most evident in the Iberian Peninsula. One of the important gaps in the European distribution of P. ripartii is reduced by the discovery of new Croatian populations, which also facilitate a better understanding of the biogeography of the species. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109, 817-829. [ABSTRACT FROM AUTHOR]