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The phylogeographic structures of two European rodents, the Yellow-necked fieldmouse (Apodemus flavicollis) and the Wood mouse (Apodemus sylvaticus) were compared on the basis of mitochondrial DNA cytochrome b(mt DNA cyt b). The results indicated that the two species survived in different ways through the Quaternary glaciations, and suggested phylogeographic distinctiveness, a general feature of European species.

This study establishes the continental phylogeographical pattern of a European nematode,Heligmosomoides polygyrus(Dujardin, 1845; Heligmosomoidea). We sequenced 687 base pairs of the mitochondrial DNA (mtDNA)cyt bgene for 136 individuals collected in 22 localities. The results revealed thatH. polygyruspopulations are separated into five major units corresponding to the Italian, northern European (Denmark and Ireland), Iberian, western European, and Balkan populations. Different subclades were also observed within the first two groups. Based on the rate of molecular evolution ofH. polygyrus cyt bgene-estimated to 3.5%–3.7% divergence per million years (Myr) in a previous study– the isolation time of the five clades was estimated between 2.5± 0.24 and 1.5± 0.23 million years ago. Moreover,H. polygyruspresents a higher genetic variability in the Mediterranean peninsulas as compared to northwestern Europe, highlighting the role of these regions as refuge areas. Like its specific host, the wood mouseApodemus sylvaticus,H. polygyrus’ pattern of postglacial recolonization of northwestern Europe was initiated from Iberian populations, while Italian and Balkan populations did not expand to the north. The results also suggest the existence of forested and temperate refuges in the southern British Isles during the Quaternary. Finally, the genetic diversity as well as the level of genetic divergence between the lineages ofH. polygyrusare compared to those observed in other vertebrate and invertebrate phylogeographical studies: the existence of highly differentiated lineages inH. polygyrus(5%−10% of genetic divergence) highlights that the effects of Pleistocene climate changes on free-living organisms are also reflected in their obligate parasites. [ABSTRACT FROM AUTHOR]

Two new species of Luciobarbus are described from the Mediterranean Sea basin in Morocco and Algeria. Their monophyly and phylogenetic placement are resolved by molecular analyses using two mitochondrial markers (cyt b and D-loop). Luciobarbus lanigarensis, new species, from the Tafna River drainage in Algeria and Morocco, is distinguished by having orange fins, a great predorsal length (52-59% SL) and a very long pectoral fin (79-90% HL). Luciobarbus numidiensis, new species, from the El-Kébir River drainage in Algeria, is distinguished by having a golden pectoral-fin margin, 43-47+1-3 lateral line scales and a very long anal-fin (19-23%).

Cyprinids of the genus Luciobarbus are the most abundant and widespread fishes in most freshwater ecosystems in the Maghreb. In the Mediterranean basin of Morocco, Algeria and Tunisia, all species of Luciobarbus-with exception of L. guercifensis-are superficially very similar and are distinguished mostly by minor morphometric characters. Molecular characters distinguish all species well and nine species are recognised from the area, two of them described here. Luciobarbus chelifensis, from the Chelif River drainage in Algeria, is distinguished by having 41-43+1-2 lateral line scales and a very short anal fin (18-19% SL). Luciobarbus mascarensis, from the Macta River drainage in Algeria, is distinguished by having usually 41+1-2 lateral line scales, a long anal-fin (19-22%) and a short caudal peduncle (15-17% SL). An identification key is given for all African Mediterranean Luciobarbus species except for L. callensis and L. rifensis, which could not be distinguished.

Climatic variations during the Quaternary period had a considerable impact on landscapes and habitat fragmentation (rivers) in North Africa. These historical events can have significant consequences on the genetic structure of the populations. Indeed, geographically separated and genetically isolated populations tend to differentiate themselves through time, eventually becoming distinct lineages, allowing new species to emerge in later generations. The aim of the present study is to use genetic and morphological techniques to evaluate the major role of the Saalian glaciation (Middle Quaternary) in the establishment of the geographic space and in the evolution of the intraspecific genetic diversity, by tracing the demographic history of barbels belonging to the Luciobarbus pallaryi (Cyprinidae) species in the Guir Basin (Algeria). In this context, two populations, from two distinct and isolated sites, were studied. Analysis of the cytochrome b (cyt b) mitochondrial markers and of the "D-loop" control region has shown that the "upstream" and "downstream" Guir populations are genetically differentiated. The molecular analyses suggest that the upstream population was disconnected from this hydrographic system during the Saalian glaciation period of the Quaternary. Subsequently, it was isolated in the foggaras underground waters in the Great Western Erg, at approximately 320 000 years BP, creating, through a bottleneck effect, a new allopatric lineage referred to as "Adrar". Conversely, the high genetic diversity in the upstream Guir (Bechar) population suggests that the stock is globally in expansion. These barbels (n=52) were also examined with meristic, morphometric, osteological, and biological features. These data also reveal a complete discrimination between the two populations, with a remarkable and distinctive behavioural adaptation for the Adrar specimens: neoteny., (Copyright © 2016 Académie des sciences. Published by Elsevier SAS. All rights reserved.)

The Pyrenean region exhibits high levels of endemism suggesting a major contribution to the phylogeography of European species. But, to date, the role of the Pyrenees and surrounding areas as a glacial refugium for temperate species remains poorly explored. In the current study, we investigated the biogeographic role of the Pyrenean region through the analyses of genetic polymorphism and morphology of a typical forest-dwelling small mammal, the bank vole (Myodes glareolus). Analyses of the mitochondrial cytochrome b gene and the third upper molar (M(3)) show a complex phylogeographic structure in the Pyrenean region with at least three distinct lineages: the Western European, Spanish and Basque lineages. The Basque lineage in the northwestern (NW) Pyrenees was identified as a new clearly differentiated and geographically localized bank vole lineage in Europe. The average M(3) shape of Basque bank voles suggests morphological differentiation but also restricted genetic exchanges with other populations. Our genetic and morphological results as well as palaeo-environmental and fossils records support the hypothesis of a new glacial refugium in Europe situated in the NW Pyrenees. The permissive microclimatic conditions that prevailed for a long time in this region may have allowed the survival of temperate species, including humans. Moreover, local differentiation around the Pyrenees is favoured by the opportunity for populations to track the shift of the vegetation belt in altitude rather than in latitude. The finding of the Basque lineage is in agreement with the high level of endemic taxa reported in the NW Pyrenees.

Domestic fleas were collected in 12 villages in the western Usambara Mountains in Tanzania. Of these, 7 are considered villages with high plague frequency, where human plague was recorded during at least 6 of the 17 plague seasons between 1986 and 2004. In the remaining 5 villages with low plague frequency, plague was either rare or unrecorded. Pulex irritans, known as the human flea, was the predominant flea species (72.4%) in houses. The density of P. irritans, but not of other domestic fleas, was significantly higher in villages with a higher plague frequency or incidence. Moreover, the P. irritans index was strongly positively correlated with plague frequency and with the logarithmically transformed plague incidence. These observations suggest that in Lushoto District human fleas may play a role in plague epidemiology. These findings are of immediate public health relevance because they provide an indicator that can be surveyed to assess the risk for plague.