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We provide an update of the geographical distribution and phylogenetic relationships of mitochondrial haplotype groups of the European common frog, Rana temporaria, one of the most widespread amphibians on Earth. Our data set of 378 newly determined DNA sequences of the cytochrome b gene is combined with 640 previously published sequences, mainly filling a sampling gap in the Spanish Basque country. A haplotype network based on 331 bp provides evidence for a previously unknown, deeply divergent haplogroup in this region, which in the eastern part of its range occurs sympatrically with a widespread group of haplotypes from the Pyrenean mountains, and to the West contacts a haplogroup typically for the central Cantabrian mountains. In contrast, samples from the isolated Montseny massif in the Spanish region of Catalonia are not differentiated from Pyrenean populations. Samples from Scotland cluster in a widespread haplogroup with samples from northern France, western Germany, and Ireland. Our data furthermore suggest that previous records of haplotype sharing of British R. temporaria populations with those from northwestern Spain are probably erroneous. A phylogenetic analysis based on 4,413 bp of mitochondrial DNA confirms the strong divergence of the newly discovered Basque haplogroup and indicates that it might be the sister group of a clade containing all other R. temporaria haplogroups. [ABSTRACT FROM AUTHOR]

The strawberry poison frog (Oophagapumilio), occurring from Panama to northern Nicaragua, is characterized by an extraordinary variation of aposematic colouration and pattern in some Panamanian populations and has become a model system for studying evolutionary and ecological processes. Phylogeographic analyses of this species so far included populations from Panama and Costa Rica only. Based on newly collected samples from representative sites across Nicara-gua, we here extend an existing data set of mitochondrial DNA sequences of the cytochrome b gene to analyse the phylo-geographic history of O. pumilio. The 62 sequenced samples from seven localities are more closely related to the northern clade of O. pumilio, four haplotypes are shared amongst populations from Costa Rica and southern Nicaragua, and one haplotype is shared amongst Costa Rica and northern Nicaragua. An analysis of colour patterns reveals slight differences within and amongst Nicaraguan populations, but all of them conform to the general pattern found also in Costa Rica, with a reddish dorsum and blue coloured limbs. Phylogeographic analysis suggests that the Nicaraguan populations originated by a Late Pleistocene range expansion northwards, and reconstructs the origin of the species in southeastern Costa Rica [ABSTRACT FROM AUTHOR]

The unpredictable and low cross-amplification success of microsatellite loci tested for congeneric amphibian species has mainly been explained by the size and complexity of amphibian genomes, but also by taxonomy that is inconsistent with phylogenetic relationships among taxa. Here, we tested whether the cross-amplification success of nine new and 11 published microsatellite loci cloned for an amphibian source species, the fire salamander ( Salamandra salamandra), correlated with the genetic distance across all members of True Salamanders (genera Chioglossa, Lyciasalamandra, Mertensiella and Salamandra that form a monophyletic clade within the family of Salamandridae) serving as target species. Cross-amplification success varied strongly among the species and showed a highly significant negative relationship with genetic distance and amplification success. Even though lineages of S. salamandra and Lyciasalamndra have separated more than 30 Ma, a within genus amplification success rate of 65% was achieved for species of Lyciasalamandra thus demonstrating that an efficient cross-species amplification of microsatellite loci in amphibians is feasible even across large evolutionary distances. A decrease in genome size, on the other hand, paralleled also a decrease in amplified loci and therefore contradicted previous results and expectations that amplification success should increase with a decrease in genome size. However, in line with other studies, our comprehensive dataset clearly shows that cross-amplification success of microsatellite loci is well explained by phylogenetic divergence between species. As taxonomic classifications on the species and genus level do not necessarily mirror phylogenetic divergence between species, the pure belonging of species to the same taxonomic units (i.e. species or genus) might be less useful to predict cross-amplification success of microsatellite loci between such species. [ABSTRACT FROM AUTHOR]

Madagascar is a biodiversity hotspot particularly rich in amphibian diversity and only a few charismatic Malagasy amphibians have been investigated for their population-level differentiation. The Mantella madagascariensis group is composed of two rainforest and three swamp forest species of poison frogs. We first confirm the monophyly of this clade using DNA sequences of three nuclear and four mitochondrial genes, and subsequently investigate the population genetic differentiation and demography of the swamp forest species using one mitochondrial, two nuclear and a set of nine microsatellite markers. Our results confirm the occurrence of two main mitochondrial lineages, one dominated by Mantella aurantiaca (a grouping supported also by our microsatellite-based tree) and the other by Mantella crocea + Mantella milotympanum. These two main lineages probably reflect an older divergence in swamp Mantella. Widespread mitochondrial introgression suggests a fairly common occurrence of inter-lineage gene flow. However, nuclear admixture seems to play only a limited role in this group, and the analyses of the RAG-1 marker points to a predominant incomplete lineage sorting scenario between all five species of the group, which probably diverged relatively recently. Our demographic analyses show a common, severe and recent demographic contraction, inferred to be in temporal coincidence with the massive deforestation events that took place in the past 1000 years. Current data do not allow to conclusively delimit independent evolutionary units in these frogs, and we therefore refrain to suggest any taxonomic changes. [ABSTRACT FROM AUTHOR]

We reconstruct range-wide phylogeographies of two widespread and largely co-occurring Western Palearctic frogs, Rana temporaria and R. dalmatina. Based on tissue or saliva samples of over 1000 individuals, we compare a variety of genetic marker systems, including mitochondrial DNA, single-copy protein-coding nuclear genes, microsatellite loci, and single nucleotide polymorphisms (SNPs) of transcriptomes of both species. The two focal species differ radically in their phylogeographic structure, with R. temporaria being strongly variable among and within populations, and R. dalmatina homogeneous across Europe with a single strongly differentiated population in southern Italy. These differences were observed across the various markers studied, including microsatellites and SNP density, but especially in protein-coding nuclear genes where R. dalmatina had extremely low heterozygosity values across its range, including potential refugial areas. On the contrary, R. temporaria had comparably high range-wide values, including many areas of probable postglacial colonization. A phylogeny of R. temporaria based on various concatenated mtDNA genes revealed that two haplotype clades endemic to Iberia form a paraphyletic group at the base of the cladogram, and all other haplotypes form a monophyletic group, in agreement with an Iberian origin of the species. Demographic analysis suggests that R. temporaria and R. dalmatina have genealogies of roughly the same time to coalescence (TMRCA ~3.5 mya for both species), but R. temporaria might have been characterized by larger ancestral and current effective population sizes than R. dalmatina. The high genetic variation in R. temporaria can therefore be explained by its early range expansion out of Iberia, with subsequent cycles of differentiation in cryptic glacial refugial areas followed by admixture, while the range expansion of R. dalmatina into central Europe is a probably more recent event., (Copyright © 2013 Elsevier Inc. All rights reserved.)