Austropotamobius torrentium (SCHRANK, 1803) is the smallest of the European native crayfish species and has probably never been of economic interest. It is confined to headwaters and adapted to cold water with high flow through and rocky environments. These properties make the stone crayfish a useful species for population genetics and phylogeographic studies. Representatives were collected from 18 localities throughout southern Germany and analysed with two mitochondrial genetic markers. Initial results revealed that German populations of A. torrentium from the Danube and Rhine tributaries share identical haplotypes in 528 basepairs of 16S rRNA and 658 basepairs of the COI gene. Rare haplotypes of the COI genes were occasionally encountered and apparently restricted to southwestern Bavaria. Only three variable sites were found over a length of 658 basepairs in 45 German, Swiss and Austrian stone crayfish resulting in five different haplotypes, with the prevalence of one most common haplotype. Here we show that in German populations rare haplotypes are not randomly distributed, but found in higher frequencies in the Bavarian Alps of the Allgäu and in adjacent Tyrol. On the other hand, stone crayfish population from the Bavarian Forest and the Rhine tributaries appear genetically impoverished, so far only showing the most common haplotype. Consequently, there are significant differences between the Allgäu populations and the rest of the German populations in haplotype frequencies, resulting in a relatively high FST value. This finding is of importance for future conservation efforts of stone crayfish populations in Germany and Austria. Austropotamobius torrentium (SCHRANK, 1803) est la plus petite des espèces d’écrevisses natives d’Europe et n’a probablement jamais eu d’intérêt économique. Elle est confinée au cours supérieur des rivières et est adaptée aux eaux froides à fort courant et avec un environnement rocailleux. Ces propriétés font de l’écrevisse des torrents une espèce utile pour les études de génétique des populations et de phylogéographie. Des échantillons ont été prélevés dans 18 localités réparties dans toute le Sud de l’Allemagne, puis analysés avec deux marqueurs génétiques mitochondriaux. Les premiers résultats ont montré que les populations allemandes d’A. torrentium des affluents du Danube et du Rhin ont le même haplotype pour une séquence de 528 paires de bases d’ARNr 16S et pour une séquence de 658 paires de bases du gène COI. Des haplotypes rares du gène COI ont été occasionnellement rencontrés, cantonnés apparemment dans le Sud de la Bavière. Parmi 45 écrevisses des torrents d’Allemagne, de Suisse et d’Autriche, seuls trois sites variables ont été trouvés sur une longueur de 658 paires de bases, conduisant à cinq haplotypes différents parmi lesquels prévaut un haplotype très répandu. Ici nous montrons que dans les populations germaniques, les haplotypes rares n’ont pas une distribution aléatoire mais se trouvent en fréquence plus élevée dans les Alpes bavaroises de l’Allgäu et dans le Tyrol adjacent. D’un autre côté, les populations d’écrevisse des torrents de la Forêt Bavaroise et des affluents du Rhin semblent tellement appauvries génétiquement qu’elles ne présentent que l’haplotype commun. Par conséquent, il y a des différences significatives entre les populations d’Allgäu et le reste des populations allemandes au niveau de la fréquence des haplotypes, conduisant à un FST relativement élevé. Ce résultat est important pour les mesures de conservation à venir des populations d’écrevisse des torrents en Allemagne et en Autriche

The faunal and floral relationship of northward-drifting India with its neighboring continents is of general biogeographic interest as an important driver of regional biodiversity. However, direct biogeographic connectivity of India and Southeast Asia during the Cenozoic remains largely unexplored. We investigate timing, direction and mechanisms of faunal exchange between India and Southeast Asia, based on a molecular phylogeny, molecular clock-derived time estimates and biogeographic reconstructions of the Asian freshwater crab family Gecarcinucidae.

Ancient lakes are among the most stable freshwater environments on our planet, with a species richness far exceeding that of younger and less stable l

The American blue crab Callinectes sapidus is a particularly successful invader in estuarine ecosystems worldwide. Despite increasing awareness of its potential harm, the invasion history and underlying genetic diversity of this species within the Mediterranean Sea remain unknown. This study constitutes the first large-scale approach to study phylogeographic patterns of C. sapidus in Europe, facilitated by the first comparison of all currently available COI sequence data. For this investigation, 71 individuals of C. sapidus were newly analyzed and the entire COI gene was sequenced and used for a comparative phylogeographic analyses. For the first time, two separately used adjacent regions of this gene were combined in a single dataset. This allowed emphasizing the prevalence of three geographically defined lineages within the native range: (1) eastern North America, including the Gulf of Mexico, (2) the Caribbean, and (3) Brazil. New data from the Mediterranean reveal that non-native populations of C. sapidus are characterized by a conspicuously low genetic diversity (except for Turkey, where stocking took place), and that there is surprisingly low connectivity among established populations. The occurrence of strong genetic bottlenecks suggests few founder individuals. This confirms that, even under a scenario of restricted large-scale gene flow, a very limited number of invasive individuals is sufficient for a massive impact.

During past glacial periods, many species of forest-dwelling animals experienced range contractions. In contrast, species living outside such moist habitats appear to have reacted to Quaternary changes in different ways. The Atlantic Forest represents an excellent opportunity to test phylogeographic hypotheses, because it has a wide range of vegetation types, including unforested habitats covered predominantly by herbaceous and shrubby plants, which are strongly influenced by the harsh environment with strong wind and high insolation. Here, we investigated the distribution of genetic diversity in the endemic sand dune ant Mycetophylax simplex across its known range along the Brazilian coast, with the aim of contributing to the understanding of alternative phylogeographic patterns. We used partial sequences of the mitochondrial gene cytochrome oxidase I and nuclear gene wingless from 108 specimens and 51 specimens, respectively, to assess the phylogeography and demographic history of this species. To achieve this we performed different methods of phylogenetic and standard population genetic analyses. The observed genetic diversity distribution and historical demographic profile suggests that the history of M. simplex does not match the scenario suggested for other Atlantic Forest species. Instead, it underwent demographic changes and range expansions during glacial periods. Our results show that M. simplex presents a shallow phylogeographic structure with isolation by distance among the studied populations, living in an almost panmictic population. Our coalescence approach indicates that the species maintained a stable population size until roughly 75,000 years ago, when it underwent a gradual demographic expansion that were coincident with the low sea-level during the Quaternary. Such demographic events were likely triggered by the expansion of the shorelines during the lowering of the sea level. Our data suggest that over evolutionary time M. simplex did not undergo dramatic range fragmentation, but rather it likely persisted in largely interconnected populations. Furthermore, we add an important framework about how both glacial and interglacial events could positively affect the distribution and diversification of species. The growing number of contrasting phylogeographic patterns within and among species and regions have shown that Quaternary events influenced the distribution of species in more ways than first supposed.