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To reconstruct the phylogeographic history of the Holarctic carnivorous genus Leptodora (Crustacea: Cladocera: Haplopoda). We studied the DNA of between one and five specimens each from 28 populations distributed across the Holarctic, but with emphasis on Eurasia. We sequenced a mitochondrial (cytochrome c oxidase subunit I) and a nuclear (elongation factor-1α) gene, and combined this molecular information with geological and palaeoclimatological data. Haplotype networks and phylogenetic trees were constructed using a Bayesian and maximum likelihood approach. A molecular clock was applied. Leptodora consists of three clades ( Leptodora kindtii in Europe, Leptodora richardi in China and Japan, and Leptodora sp. in North America), with insular subclades in Japan and in the eastern Mediterranean. The North American clade was not studied in detail. Leptodora richardi is the more thermophilic of the three. It extends from the Tropic of Cancer in the south to the Heilong Basin in the north. The western European L. kindtii is more cold-water adapted than the eastern Mediterranean subclade. 'West European' and 'Chinese' clades are broadly separated by a hybrid zone in Siberia and European Russia as far west as the Volga. These hybrids have the mitochondrial DNA of L. kindtii, the nuclear DNA of L. richardi and the low-temperature preference of L. kindtii, and may have formed as recently as the Holocene hypsithermal. A pure L. kindtii population in the Upper Irtysh catchment, east of the Dzungarian Gates, has been sequestered in endorheic Lake Wulungu, Xinjiang, since the mid-Pleistocene. Application of a molecular clock places the most recent common ancestor of the North American, East Asian and European populations in the mid-Miocene. The North American taxon is still living in isolation, while the Eurasian taxa, separated by the Alpine folding, made contact again in the Pleistocene, when the cold-stenothermic L. kindtii repeatedly moved eastwards across Siberia and back. The population in Xinjiang is a relict of an early wave coming from western Europe: it crossed the Dzungarian Gates during a humid mid-Pleistocene event, probably corresponding to the Apsheron transgression in the Caspian Basin. Later aridity isolated it there, and it started accumulating private haplotypes. The Holocene Euro-Siberian hybrid zone may eventually engulf all European populations. [ABSTRACT FROM AUTHOR]

Aim The clade Campanulaceae in the Cretan area is rich in endemics, with c. 50% of its species having restricted distributions. These species are analysed in the context of a larger phylogeny of the Campanulaceae. Divergence times are calculated and hypotheses of vicariance and dispersal are tested with the aim of understanding whether Cretan lineages represent remnants of an older continental flora. Location The Cretan area: Crete and the Karpathos Islands (Greece). Methods We obtained chloroplast DNA sequence data from rbcL, atpB and matK genes for 102 ingroup taxa, of which 18 are from the Cretan area, 11 are endemics, and two have disjunct, bi-regional distributions. We analysed the data usingbeast, a Bayesian approach that simultaneously infers the phylogeny and divergence times. We calibrated the tree by placing a seed fossil in the phylogeny, and used published age estimates as a prior for the root. Results The phylogenetic reconstruction shows that all Campanula species fall within a well-supported campanuloid clade; however, Campanula is highly polyphyletic. The Cretan endemics do not form a monophyletic group, and species are scattered throughout the campanuloid clade. Therefore, the Cretan taxa did not evolve following a single vicariance or dispersal event. Most Cretan lineages represent remnants of an older continental flora, with the exception of one clade that radiated in situ after island isolation, and one lineage that appears to have arrived by dispersal. Main conclusions Most Cretan species were present in the islands at the time of their isolation, and very little long-distance dispersal to Crete and diversification within Crete has occurred since then. Endemism is probably driven by loss of species on the mainland after island isolation. Species on the islands may have been more widespread in the past, but they are now restricted to often inaccessible areas, probably as a result of human pressure. [ABSTRACT FROM AUTHOR]

Aim To reconstruct the temporal, geographical and eco-climatological differentiation of the genus Anthemis (Compositae, Anthemideae) in the circum-Mediterranean region, in order to evaluate the relative importance of geographical vs. climatological differentiation processes in influencing the actual distribution patterns in this plant group. Location The circum-Mediterranean region, including the Iberian Peninsula, northern Africa, the Italian and Balkan peninsulas, the Aegean region and Anatolia, the Caucasus, the Arabian Peninsula and western Asia. Methods The phylogeny of the genus Anthemis was obtained from a maximum likelihood analysis based on nuclear ribosomal DNA (nrDNA) internal transcribed spacer (ITS) sequence data, and the chronology of diversification was derived using a penalized likelihood approach. The reconstruction of the spatial diversification of the genus was based on a dispersal/vicariance (DIVA) analysis. Eco-climatological niche differentiation was inferred by optimizing 19 bioclimatic variables onto the phylogeny. A multi-dimensional hypervolume, proposed as a representation of the eco-climatological niche and defined by the combination of ranges for all bioclimatic variables, was calculated for each taxon and each internal node. To identify ‘eco-climatological vicariance’ events in the phylogeny, the pairwise overlap among hypervolumes of sister groups was calculated. Finally, the temporal and clade-wise relative importance of geographical vs. eco-climatological vicariance events was estimated. Results The temporal reconstruction shows a constant increase of lineages through the last 12 Myr. The geographical reconstruction suggests that Anthemis diverged from the rest of the Compositae–Anthemideae in the eastern Mediterranean region, and from there radiated into the whole circum-Mediterranean region through successive dispersal and vicariance events. The reconstruction of the eco-climatological niches suggests a progressive adaptation from a montane-humid climate towards arid environments and the typical mediterranean climate. Main conclusions The results presented here involved phylogenetic, geographical and eco-climatological reconstructions; joint analyses of all of these aspects have assessed the relative importance of geological vs. climatic forces that have affected the distributional history of the genus Anthemis. Large-scale differentiation patterns triggered by geological forces appear to have influenced the evolutionary history of the genus in a rather constant manner over the last 12 Myr, whereas climatic forces seem to have played an important role in two phases of the radiation process: at around 9 Ma, when the area experienced the onset of a trend towards aridification, and during the last 3.5 Myr, with the establishment of the typical mediterranean climate and the influence of Pleistocene climate oscillations. [ABSTRACT FROM AUTHOR]

Aim Various data sets and methods of analysis were combined to produce the first comprehensive molecular phylogeny of the genus Tuber and to analyse its biogeography . Location Europe, North Africa, China, Asia, North America. Methods Phylogenetic relationships among Tuber species were reconstructed based on a data set of internal-transcribed spacer (ITS) sequences and various phylogenetic inference methods, specifically maximum parsimony, Bayesian analysis and neighbour joining. Tajima’s relative rate test showed that Tuber 18S rRNA, 5.8S rRNA, 5.8S-ITS2 rRNA and β-tubulin sequences evolved in a clock-like manner. These genes, combined or not, were employed for molecular clock estimates after construction of linearized trees usingmega 3.1. We reconstructed ancestral areas in the Northern Hemisphere by means of a dispersal–vicariance analysis (diva 1.1) based on current distribution patterns of the genus Tuber determined from the literature. Results The resulting molecular phylogeny divided the genus Tuber into five distinct clades, in agreement with our previously published studies. The Puberulum, Melanosporum and Rufum groups were diversified in terms of species and geographical distribution. In contrast, the Aestivum and Excavatum groups were less diversified and were located only in Europe or North Africa. Using a global molecular clock analysis, we estimated the divergence times for the origin of the genus and for the origin of several groups.diva inferred nine dispersal events and suggested that the ancestor of Tuber was originally present in Europe or was widespread in Eurasia. Equally optimal distributions were obtained for several nodes, suggesting different possible biogeographical patterns. Main conclusions Our analyses identified several discrepancies with the classical taxonomy of the genus, and we propose a new phylogenetic classification. According to molecular clocks, the radiation of the genus Tuber could have started between 271 and 140 Ma. Used in combination with the results obtained from time divergence estimates, this allows us to propose two equally probable scenarios of intra- and inter-continental diversification of the genus according to the geographic distribution of the most recent common ancestor in Europe or Eurasia. The biogeographical patterns imply intra-continental dispersal events between Europe and Asia and inter-continental dispersal events between North America and Europe or Asia, which are compatible with land connections during the Tertiary. [ABSTRACT FROM AUTHOR]