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The common hamster (Cricetus cricetus L.), a rodent of the Eurasian steppes and agricultural areas, is threatened by habitat loss. Remnant populations in Western and Central Europe are small, isolated and genetically impoverished. The populations of Belgium, The Netherlands and North Rhine-Westphalia, Germany (BNN), for which Nehring proposed the epiphet canescens, are most affected by this decline. They are distinguished from more eastern populations by large, white areas on throat, chest and forelegs. These traits are sometimes also found in other populations, which casts doubt on their value as diagnostic characteristics. Here, we show that the frequency of occurrence of relatively large chest spots, chin streaks and cuffs on the forelegs is highest in BNN, where a white chest spot occurs in 67–100 % of the sampled individuals, compared to 0–8 % in Central and Eastern European populations. Additionally, hamsters from the Upper Rhine area also display relatively high frequencies of these characters (7–44 %). This suggests a common origin of BNN and Upper Rhine hamsters and an ancient expansion route along the Rhine Valley. A supplementary genetic study of two mitochondrial genes revealed extremely low diversity in both BNN and Upper Rhine hamsters but also clear differentiation and isolation between the two remaining relict populations of North Rhine-Westphalia.
Tropical West Africa has a high diversity of bats, which are relatively poorly studied. In this baseline biodiversity assessment of bats in the Simandou Mountain Range of southeastern Guinea (Guinea Forestiére), 312 individual bats belonging to 26 species were captured, four of which represent new species records for the country. Combined with the results of a previous survey, 35 bat species have been recorded at Simandou to date, including a new species (Neoromicia sp. nov.), which we describe here, and an additional species potentially new to science. A neotype for Neoromicia tenuipinnis is designated. We present an annotated checklist of the bats at Simandou and neighbouring sites, including some pertinent field notes on their habitat requirements and conservation status. Furthermore, we discuss the estimated maximum species richness and show that Simandou supports one of the most diverse bat communities in tropical Africa. Finally, we outline conservation concerns with respect to bats in the face of the iron ore extraction activities at Simandou.
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