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Conflicting phylogenetic signals of two data sets that analyse different portions of the same molecule are unexpected and require an explanation. In the present paper we test whether (i) differential evolution of two mitochondrial genes or (ii) cryptic diversity can better explain conflicting results of two recently published molecular phylogenies on the same set of species of long-eared bats (genus Plecotus). We sequenced 1714 bp of three mitochondrial regions (16S, ND1, and D-loop) of 35 Plecotus populations from 10 European countries. A likelihood ratio test revealed congruent phylogenetic signals of the three data partitions. Our phylogenetic analyses demonstrated that the existence of a previously undetected Plecotus lineage caused the incongruities of previous studies. This lineage is differentiated on the species level and lives in sympatry with its sister lineage, Plecotus auritus, in Switzerland and Northern Italy. A molecular clock indicates that all European Plecotus species are of mid or late Pliocene origin. Plecotus indet. was previously described as an intergrade between P. auritus and Plecotus austriacus since it shares morphological characters with both. It is currently known from elevations above 800 m a.s.l. in the Alps, the Dinarian Alps and the Pindos mountains in Greece. Since we could demonstrate that incongruities of two molecular analyses simply arose from the mis-identification of one lineage, we conclude that molecular phylogenetic analyses do not free systematists from a thorough inclusion of morphological and ecological data. [Copyright &y& Elsevier]

Introduction: The progressive ageing of the population is one of the main socio-demographic phenomena, taking place at a global level. Several recent population-based studies conducted worldwide suggest that the age-specific risk of dementia may be changing in some countries and areas., Evidence Acquisition: This systematic review was performed using the methodology proposed by the Cochrane handbook for systematic reviews and reported following the PRISMA statement. A structured bibliographic search was performed on the databases PubMed, ISI Web of Science and the Cochrane Database of Systematic Reviews. All included studies were qualitatively assessed using the Methodological Evaluation of Observational REsearch (MORE)., Evidence Synthesis: The bibliographic search yielded 2394 records. Three more articles were retrieved from other sources. A total of ten studies were included, five reported data on a possible reduction in the prevalence of dementia, and five reported data on a possible reduction in its incidence., Conclusions: The present systematic review focused on the recent observations of a possible decrease in the frequency of dementia and cognitive impairment in some Western countries (USA, UK, Sweden, the Netherlands, France, Iceland) between 1977 and 2014. The included studies have a high heterogeneity in terms of the clinical criteria used to diagnose dementia, and of the criteria used to define the clinical condition preceding dementia, such as isolated cognitive impairment. Moreover, the methodological quality with which they were conducted was also heterogeneous, with scores ranging from 1 to 7 using the MORE tool.

Background: Dementia, including Alzheimer's disease (AD), is one of the most burdensome medical conditions. Usually, the reviews that aim at calculating the prevalence of dementia include estimates from studies without assessing their methodological quality. Alzheimer's Disease International (ADI) proposed a score to assess the methodological quality of population-based studies aimed at estimating the prevalence of dementia. During the last three years, the European Commission has funded three projects (Eurodem, EuroCoDe, and ALCOVE) in order to estimate the prevalence of dementia in Europe., Objective: The aim of this study was to perform a systematic review and meta-analysis of data on the prevalence of dementia in Europe derived from studies that included only subjects with a diagnosis of dementia according to the DSM IV criteria, and that had a high quality score according to ADI criteria., Methods: We considered the studies selected by the two projects EuroCoDe (1993-2007) and Alcove (2008-2011), and we performed a new bibliographic search. For the systematic review, we only selected the subset of articles that included subjects with a diagnosis of dementia according to the DSM IV criteria. The studies were qualitatively assessed using the ADI tool., Results: The meta-analysis considered 9 studies that were carried out in Europe between 1993 and 2018 including a total of 18,263 participants, of which 2,137 were diagnosed with dementia. The prevalence rate standardized for age and sex resulted 7.1%., Discussion: This is the first systematic review on the prevalence of dementia in Europe considering only high-quality studies adopting the same diagnostic criteria (i.e., DSM IV).

Different species of bat can be morphologically very similar. In order to estimate the amount of cryptic diversity among European bats we screened the intra- and interspecific genetic variation in 26 European vespertilionid bat species. We sequenced the DNA of subunit 1 of the mitochondrial protein NADH dehydrogenase (ND1) from several individuals of a species, which were sampled in a variety of geographical regions. A phylogeny based on the mitochondrial (mt) DNA data is in good agreement with the current classification in the family. Highly divergent mitochondrial lineages were found in two taxa, which differed in at least 11% of their ND1 sequence. The two mtDNA lineages in Plecotus austriacus correlated with the two subspecies Plecotus austriacus austriacus and Plecotus austriacus kolombatovici. The two mtDNA lineages in Myotis mystacinus were partitioned among two morphotypes. The evidence for two new bat species within Europe is discussed. Convergent adaptive evolution might have contributed to the morphological similarity among distantly related species if they occupy similar ecological niches. Closely related species may differ in their ecology but not necessarily in their morphology. On the other hand, two morphologically clearly different species (Eptesicus serotinus and Eptesicus nilssonii) were found to be genetically very similar. Neither morphological nor mitochondrial DNA sequence analysis alone can be guaranteed to identify species.

The analysis of morphological, behavioural and genetic characters of whiskered bats revealed a new European bat species within the family Vespertilionidae. We describe the morphology, karyology, genetic similarity, ecology and distribution of Myotis alcathoe n. sp. It closely resembles Myotis mystacinus, Myotis brandtii and Myotis ikonnikovi in morphology, but all four species show clear genetic differences in two mitochondrial genes (ND1 and 12S rRNA). Myotis alcathoe n. sp. is the smallest species among the European whiskered bats and uses the highest-frequency echolocation calls of all the European Myotis species. It prefers to hunt in small valleys with deciduous trees and flowing water, which is an endangered habitat. Records from Greece and Hungary indicate a distribution range in south-eastern Europe.

Although rarely assessed, the population genetics of hibernating colonies can help to understand some aspects of population structure, even when samples from nursery or mating colonies are not available, or in studies of migration when both types of samples are available and can be compared. Here we illustrate both points in a survey of mitochondrial DNA (mtDNA) control region sequences used to study the population genetics of hibernating colonies of a migrating species, the noctule bat (Nyctalus noctula). Lacking samples from Scandinavian nursery colonies, we use a North European hibernacula to suggest that Scandinavian populations are isolated from Central and East European colonies. Then, we compare genetic diversities of nursery and hibernating colonies. We find a significantly higher haplotype diversity in hibernacula, confirming that they consist of individuals from different nursery colonies. Finally, we show that pairwise comparisons of the haplotype frequencies of nursery and hibernating colonies contain some information on the migration direction of the noctule bat.

Studying the dispersal behaviour of small, volant, and nocturnal animals such as microchiropterans with direct methods (banding--recapture, telemetry) is a very difficult task. The development of easily scorable and highly variable genetic markers nowadays allows us to study some aspects of dispersal indirectly, using population genetics. Here, we applied these indirect methods to characterize male dispersal behaviour in a European bat species. The eight microsatellite loci analysed were highly variable in all the nursing colonies assessed (h = 0.63-0.93). Contrary to what we found in the mtDNA, an AMOVA and F-statistics showed that the overall European population structure of the noctule bat was very weak, indicating a high male dispersal rate. Nevertheless, the population was not totally panmictic (theta = 0.006, p < 0.001), and neither isolation by distance, nor influence of migration could account for this result. Rather, an analysis of pairwise theta-values showed that the population structure might be explained partly by a geographical barrier to gene flow (the Alps), and partly by the fact that there is some limit to the distance the males can disperse.