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The present phylogeographic pattern of red deer in Eurasia is not only a result of the contraction of their distribution range into glacial refugia and postglacial expansion, but probably also an effect of replacement of some red deer s.l. mtDNA lineages by others during the last 50 000 years. To better recognize this process, we analysed 501 sequences of mtDNA cytochrome b , including 194 ancient and 75 contemporary samples newly obtained for this study. The inclusion of 161 radiocarbon-dated samples enabled us to study the phylogeny in a temporal context and conduct divergence-time estimation and molecular dating. Depending on methodology, our estimate of divergence between Cervus elaphus and Cervus canadensis varied considerably (370 000 or 1.37 million years BP, respectively). The divergence times of genetic lineages and haplogroups corresponded to large environmental changes associated with stadials and interstadials of the Late Pleistocene. Due to the climatic oscillations, the distribution of C. elaphus and C. canadensis fluctuated in north–south and east–west directions. Some haplotypes dated to pre-Last Glacial Maximum periods were not detected afterwards, representing possibly extinct populations. We indicated with a high probability the presence of red deer sensu lato in south-eastern Europe and western Asia during the Last Glacial Maximum. [ABSTRACT FROM AUTHOR]

The identification and designation of land snail species in the genus Trochulus on the basis of shell characteristics are problematic because of their great phenotypic plasticity. Some genetic analyses have proved inconclusive, with much variation within populations and apparent gene flow among them. We examined this issue by morphometric and molecular approaches on the morphologically similar species T. coelomphala, T. hispidus and T. striolatus, co‐occurring in the Alpenvorland of Germany. While these species differed in shell and reproductive system morphology, there were forms that turned out intermediate in shell characters between T. coelomphala and T. hispidus but had genital morphology similar to T. coelomphala. Phylogenetic analysis, however, showed that these forms clustered neither with T. coelomphala nor T. hispidus but are sister to T. striolatus from the same region, which suggests that they evolved by way of sympatric speciation. Further, these analyses suggest that T. coelomphala diverged within T. hispidus; a crossing experiment indicated that they were interfertile. Expanding the study to include all available Trochulus sequences enabled us to infer evolutionary relationships between them and showed that T. hispidus is polyphyletic. Some Trochulus samples of one nominal species were grouped within others. The combination of phenotypic plasticity and possible mitochondrial DNA introgression illustrates the complex nature of evolutionary processes and the need for caution in the application of traditional taxonomic practice. [ABSTRACT FROM AUTHOR]

Mitochondrial genes are placed on one molecule, which implies that they should carry consistent phylogenetic information. Following this advantage, we present a well-supported phylogeny based on mitochondrial genomes from almost 300 representatives of Passeriformes, the most numerous and differentiated Aves order. The analyses resolved the phylogenetic position of paraphyletic Basal and Transitional Oscines. Passerida occurred divided into two groups, one containing Paroidea and Sylvioidea, whereas the other, Passeroidea and Muscicapoidea. Analyses of mitogenomes showed four types of rearrangements including a duplicated control region (CR) with adjacent genes. Mapping the presence and absence of duplications onto the phylogenetic tree revealed that the duplication was the ancestral state for passerines and was maintained in early diverged lineages. Next, the duplication could be lost and occurred independently at least four times according to the most parsimonious scenario. In some lineages, two CR copies have been inherited from an ancient duplication and highly diverged, whereas in others, the second copy became similar to the first one due to concerted evolution. The second CR copies accumulated over twice as many substitutions as the first ones. However, the second CRs were not completely eliminated and were retained for a long time, which suggests that both regions can fulfill an important role in mitogenomes. Phylogenetic analyses based on CR sequences subjected to the complex evolution can produce tree topologies inconsistent with real evolutionary relationships between species. Passerines with two CRs showed a higher metabolic rate in relation to their body mass. [ABSTRACT FROM AUTHOR]

The proper identification of species has significant implications for conservation and general knowledge of ecosystem variety. It is especially important for biodiversity hotspots and former Pleistocene refugia, such as the Balkans. In this paper, we evaluate the taxonomic status of the endemic Balkan species Fruticicola waldemari A. J. Wagner, 1912, using both recently collected material and museum specimens. Phylogenetic analyses based on two mitochondrial markers, 16S rRNA and cytochrome c oxidase subunit I, show that this species is closely related to the representatives of Xerocampylaea, including a conchologically similar and partly sympatric species, X. erjaveci. Analyses of shell and genital morphology as well as mitochondrial DNA sequences indicate that X. waldemari and X. erjaveci are separate but closely related species. These species differ in shell morphology (size, umbilicus diameter, microsculpture) as well as genital morphology. Nevertheless, a further study with more comprehensive sampling of both taxa is required to fully understand the complex pattern of genetic and morphological variation observed. [ABSTRACT FROM AUTHOR]

Background: Conures are a morphologically diverse group of Neotropical parrots classified as members of the tribe Arini, which has recently been subjected to a taxonomic revision. The previously broadly defined Aratinga genus of this tribe has been split into the 'true' Aratinga and three additional genera, Eupsittula, Psittacara and Thectocercus. Popular markers used in the reconstruction of the parrots' phylogenies derive from mitochondrial DNA. However, current phylogenetic analyses seem to indicate conflicting relationships between Aratinga and other conures, and also among other Arini members. Therefore, it is not clear if the mtDNA phylogenies can reliably define the species tree. The inconsistencies may result from the variable evolution rate of the markers used or their weak phylogenetic signal. To resolve these controversies and to assess to what extent the phylogenetic relationships in the tribe Arini can be inferred from mitochondrial genomes, we compared representative Arini mitogenomes as well as examined the usefulness of the individual mitochondrial markers and the efficiency of various phylogenetic methods. Results: Single molecular markers produced inconsistent tree topologies, while different methods offered various topologies even for the same marker. A significant disagreement in these tree topologies occurred for cytb, nd2 and nd6 genes, which are commonly used in parrot phylogenies. The strongest phylogenetic signal was found in the control region and RNA genes. However, these markers cannot be used alone in inferring Arini phylogenies because they do not provide fully resolved trees. The most reliable phylogeny of the parrots under study is obtained only on the concatenated set of all mitochondrial markers. The analyses established significantly resolved relationships within the former Aratinga representatives and the main genera of the tribe Arini. Such mtDNA phylogeny can be in agreement with the species tree, owing to its match with synapomorphic features in plumage colouration. Conclusions: Phylogenetic relationships inferred from single mitochondrial markers can be incorrect and contradictory. Therefore, such phylogenies should be considered with caution. Reliable results can be produced by concatenated sets of all or at least the majority of mitochondrial genes and the control region. The results advance a new view on the relationships among the main genera of Arini and resolve the inconsistencies between the taxa that were previously classified as the broadly defined genus Aratinga. Although gene and species trees do not always have to be consistent, the mtDNA phylogenies for Arini can reflect the species tree. [ABSTRACT FROM AUTHOR]

After the establishment of an endosymbiotic relationship between a proto-mitochondrion and its probable archaeal host, mitochondrial genomes underwent a spectacular reductive evolution. An interesting pathway was chosen by mitogenomes of unicellular protists called dinoflagellates, which experienced an additional wave of reduction followed by amplification and rearrangement leading to their secondary complexity. The former resulted in a mitogenome consisting of only three protein-coding genes, the latter in their multiple copies being scattered across numerous chromosomes and the evolution of complex processes for their expression. These stunning features raise a question about the future of the dinoflagellate mitochondrial genome. [ABSTRACT FROM AUTHOR]

Shrews of the Sorex genus are an evolutionarily successful group that includes more than 77 species widely distributed in Eurasia and North America. The genus is one of the rare cases where karyotypic changes reflect well the evolutionary relationships among its species. The taxa showing the greatest variation in karyotype are usually classified into the Sorex araneus group. Its evolution was associated with chromosomal rearrangements, which could have promoted fast diversification of this group into many chromosomal races and species. These processes were additionally complicated by introgressions of mitochondrial DNA, which made the evolutionary history of this group quite complex and difficult to infer. To tackle the problem, we performed multi-method phylogenetic analyses based on mitochondrial cytochrome b that is considered a good molecular marker available for many representatives of Sorex. The results were compared with phylogenies based on chromosomal rearrangement data and put into temporal and spatial context using molecular dating and historical biogeography methods. We complemented the study with the estimation of diversification rates within the S. araneus group as well as comparing the results with paleontological records and climatic oscillations within the last 4 million years. Based on the gathered data, we proposed a hypothetical scenario for the evolution and geographic dispersion of species belonging to the S. araneus group. The shrews began to diversify about 2.7 million years ago in Eurasia and then migrated at least twice to North America. The evolution of shrews was driven by Pleistocene glacial and interglacial cycles, which increased their speciation rate and the emergence of new lineages. The migrations of populations were accompanied by introgressions of mitochondrial DNA into native shrews and occurred at least twice. [ABSTRACT FROM AUTHOR]

Geographical isolation, selection and genetic drift can cause the geographical diversification of populations and lead to speciation. Land snail species in the genus Trochulus show overlaps in geographical ranges as well as in morphology, but genetic data do not always support the species-level taxonomy based on morphological characters. Such a group offers an excellent opportunity to explore the processes involved. We have addressed the problem by determining the status of the restricted endemic T. graminicola within the larger context of Trochulus taxonomy. We used an integrated approach based on morphological features, ecological preferences and two molecular markers: mitochondrial COI sequences and microsatellites. Comparison of these results demonstrated: (i) conchological distinction of T. striolatus and T. sericeus; (ii) anatomical, ecological and genetic differentiation of T. graminicola and (iii) concordance between morphological characters and mtDNA markers in T. striolatus. Moreover, our data showed an intricate evolutionary history within the genus Trochulus, which can be best explained by: (i) recent or ongoing gene flow between taxa or (ii) their large ancestral polymorphism. Both of these hypotheses suggest that diversification within this group of snails has occurred relatively recently. The mismatches between species defined on morphology and on molecular genetics indicate the complexity of the processes involved in the diversification of this genus. [ABSTRACT FROM AUTHOR]

Vertebrate mitogenomes are thought to be selected for compactness. Therefore, the increasing number of avian mitogenomes comprising duplicated regions is surprising. Such regions were proposed for at least 26 parrot genera based on the length of PCR products. However, complete mitogenomes with the duplications were shown only for six genera. These duplications evolved probably from the ancestral tRNATHR/tRNAPRO/ND6/tRNAGLU/CR and were subjected to subsequent degeneration. Here, we report the mitogenome of Poicephalus gulielmi (the subfamily Psittacinae) with a unique duplication tRNATHR/pseudoND6/CR1/tRNAPRO/ND6/tRNAGLU/CR2. This region is different from all other identified regions and resembles mostly the arrangements in Amazona and Pionus from the subfamily Arinae. [ABSTRACT FROM AUTHOR]

Medium-sized neotropical parrots from Pionus genus are represented by at least eight species. However, their taxonomy should be revised because some external morphological characters together with genetic data recognize 19 taxa. At present, only two mitochondrial markers are available for most of these taxa and obtained phylogenies are not well resolved. Therefore, we sequenced Pionus chalcopterus chalcopterus mitogenome to gain more molecular data required for future studies of the taxonomical status and phylogenetic relationships between Pionus taxa. Performed phylogenetic analyses showed seven monophyletic clades including at least two sequences assigned to one species. However, not all subspecies sequences were monophyletic. [ABSTRACT FROM AUTHOR]

Recently resurrectedPsittacaragenus is one of the 19 recognized in parrot tribeArini. The status of taxa withinPsittacararemains controversial because some forms are treated as species or subspecies depending on authorities. Evolutionary history ofPsittacarais also unclear because related phylogenetic clades contain taxa from distant and non-overlapping regions. However, the basal placement ofPsittacara leucophthalmuswith wide South American distribution suggests that other taxa with restricted range could emerge by a local split of larger population. We sequencedP. leucophthalmusmitogenome to increase the set of sequences required to determine taxonomic level and phylogeny ofPsittacarataxa. [ABSTRACT FROM PUBLISHER]

Ariniwith 19 genera is the most diversified tribe of the neotropical parrots fromArinaesubfamily. So far, among this tribe, the genusAratingaappeared to be the most problematic for the taxonomists. The typical representative of this genus isAratinga solstitialis, whose complete mitochondrial genome were sequenced and compared with five other representatives ofArinimitogenomes. Despite the conservatism in their general organization, some changes in A + T% composition of individual genes, start/stop codon usage and intergenic regions accumulated during evolution. [ABSTRACT FROM PUBLISHER]

Six genera from Arini tribe form a morphologically diverse group named macaws, which differ from other Arini in the presence of bare facial area. Macaws are further distinguished by the bare face pattern, plumage colouration and body size. Six of the eight macaw species from Ara genus can be easily segregated into three pairs according to their colouration. An exception is Ara severus, which differs from others in their size and morphology. The lack of appropriate molecular markers precludes determination of its phylogenetic position. Therefore, the mitogenome of Ara severus presented in this report will be indispensable to refine these phylogenetic relationships. [ABSTRACT FROM AUTHOR]

Arini tribe with 19 genera is the most diversified tribe of neotropical parrots. Six of them are classified as macaws and nine as conures. The presence of bare facial area distinguishes macaws from conures and other members of this tribe. However, such morphological division seems to be disputable as the smallest macaw (monotypic Diopsittaca genus) turned out to be more closely related to three monotypic conures genera (Guaruba, Leptosittaca, Thectocercus) than to other macaws. We sequenced the complete mitochondrial genome of Guaruba guarouba to enrich the resource of molecular markers for examination of phylogenetic relationships between macaws and conures. [ABSTRACT FROM AUTHOR]

The presence of bare facial area distinguishes Macaws from other members of theArinitribe. Genera and species of the Macaw group differ in pattern of this bare skin as well as in body size. Individuals of the genera:Diopsittaca,Orthopsittaca,andPrimoliusare significantly smaller than the members of the genera:Anodorhynchus,Cyanopsitta,and the most species of the genusAra. The genusPrimoliuscontains three species:P. auricollis,P. couloni,andP. maracana, which are classified as medium-sized Macaws. So far, mitochondrial genome representative for the genus was sequenced only forPrimolius coulonispecies.Primolius maracanamitogenome, which was sequenced in this study, will be indispensable to refine the phylogenetic relationships betweenPrimoliusspecies, as results of molecular researches seems to be inconsistent withPrimoliusspecies morphology. [ABSTRACT FROM PUBLISHER]

Androglossiniis one of four tribes recognized within a neotropical parrot subfamilyArinae. The tribe includes 10 genera of whichPionusis represented by eight species. However, its evolutionary diversification and relationship with otherAndroglossinimembers are still unclear. Depending on studied molecular markers,Pionusis closely related withAmazonagenus or two monotypic generaAlipiopsittaandGraydidascalusor the clade in whichAmazonagenus is sister toAlipiopsittaandGraydidascalus. Therefore, we sequencedPionus menstruus menstruusmitogenome to gain molecular data appropriate for future studies to resolve these discrepancies obtained in various phylogenetic analyses published so far. [ABSTRACT FROM PUBLISHER]