Environmental and historical effects on richness and endemism patterns of carabid beetles in the western Palaearctic

Identifying determinants of spatial diversity gradients is in the focus of biodiversity-related research and has gained considerable importance regarding global change and conservation strategies. Despite their overwhelming diversity and the crucial role of invertebrates in ecosystem functioning, our understanding of factors driving broad-scale invertebrate diversity is limited. Tackling this issue, our study analyzes macroecological patterns of a highly diverse insect taxon across large parts of the western Palaearctic. We used regression modelling to assess the influence of environmental factors on overall, widespread and restricted-range (endemic) carabid beetle diversity. Single-term regressions and variation partitioning among climatic, topographic and spatial variables showed that total carabid diversity as well as richness patterns of widespread species were most strongly correlated with spatially structured variables related to current climate (measures of ambient energy and, to a lesser degree, precipitation and AET). In contrast, restricted-range (endemic) species were most notably related to range in elevation. We discuss the possible role of this factor as a surrogate measure of historical processes and the impact of history on contemporary diversity distributions. Our results indicate that while overall diversity patterns of carabids strongly reflect current climate conditions, this primarily reflects the more widespread species, whereas the spatial distribution of restricted-range species is still significantly affected by historical processes. Thus, for a general understanding of determinants and mechanisms of broad-scale diversity, taking into account dispersal abilities and range sizes of species is essential, especially as large parts of global biodiversity are represented by invertebrates with low dispersal powers.     

Palaearctic migrants in the central Sudan

A brief account is given of the topography and climate of the Sudan and a more detailed survey is made of the vegetation and habitats afforded to wintering Palaearctic migrants in the Sahel and Soudan savannah zones in the central Sudan. Climatic conditions during the migration seasons are mentioned and the utilization of habitats by wintering migrants is broadly surveyed.
The status of 196 Palaearctic migrant species is treated briefly. The basic observational data are tabulated to summarize observed patterns of migration in terms of date, relative abundance and region (for which purpose the central Sudan is divided into four from west to east). Hitherto unpublished field notes of the authors and their collaborators are used, together with dated observations (including specimens collected) of earlier authors, to provide the fullest data on each species.
Moreau's (1967) paradox is discussed as it relates to the Sahel and Soudan savannah zones in the central Sudan, together with the degree of competition with resident African species in those zones. Some disparities between the spring and autumn abundance and d. istribution of Palaearctic migrants are discussed in relation to 40 species ana some tentative views are advanced on the possible reasons for such disparities. Evidence is adduced which points to Lanius minor and Coraczus garrulus (and possibly Circus pygargus , partially at least) having loop migrations, south through the Sudan and north through Arabia, and Falco wespertinus south through the Sudan and north through West Africa. An explanation is offered for the greater volume of water birds observed migrating down-Nile in spring compared with their volume up-Nile in autumn, and for the reversed situation observed in the region west of the Nile for these same species.
Shelduck Tadorna tadorna is included in the Sudan list for the first time.     

Phylogeography of western Palaearctic reptiles – Spatial and temporal speciation patterns

A phylogeographic analysis of eight species complexes of European reptiles was performed using different molecular methods. While mitochondrial genes (mainly cytochrome b sequences) enabled conclusions about phylogeography and differentiation, additional application of bisexually inherited markers provided information about speciation stages. As species with similar distribution patterns in southern and Central Europe were selected, matching phylogeographic patterns are useful for drawing general conclusions:

(1) The species complexes are in different stages of speciation. In some cases, cryptic species were detected.

(2) Highest genetic diversity occurs in southern Europe, the Near East and the Caucasus, regions corresponding with glacial refuges in the Iberian, Apennine and Balkan Peninsulas as well as in Turkey and the Caucasus. Often, several microrefugia must have existed in close neighbourhood. Additional microrefugia were located in southern France and in the Carpathian Basin.

(3) North Africa and the Middle East did not serve as glacial refuges for Central or northern European lineages and are typically inhabited by independent clades.

(4) Evidence for multiple range retractions and expansions, which were postulated for the times of Pleistocene climatic oscillations, could be found in the Balkans, but in Central Europe their traces have been wiped out by the last glacial. Only the Holocene invasion has left imprints in the genomes from this area.

(5) Central and northern Europe were recolonized from Balkan and Pontic refugia in the Holocene.

(6) Groups from the Iberian and Apennine Peninsulas rarely conquered other regions. This limitation can be attributed to the barrier function of the Pyrenees and the Alps.

Ecological patterns strongly impact the biogeography of western Palaearctic longhorn beetles (Coleoptera: Cerambycoidea)

We aim to unravel the biogeographic structuring of western Palaearctic longhorn beetles with focus on the location of different refugia, barriers to dispersal and postglacial range expansions with their particular filters. The interaction of different ecological features with these structures is analysed. The western Palaearctic was divided into 95 geographic entities. We produced presence-only matrices for all 955 Cerambycoidea species autochthonous to this area and derived species richness distributions and extracted faunal regions and faunal elements by cluster analyses and principal component analyses. Similar analyses were performed for sub-families and ecological groups. Longhorn beetles show a strong biogeographic structuring in the western Palaearctic. Species numbers strongly decrease to the north and west. Less mobile species and root feeders mostly contribute to the fauna of the Mediterranean region, whilst mobile species are more widespread. Feeders on broad-leaved trees dominate in western Europe, whilst feeders on coniferous trees are most important in northern Europe. Our results support multiple refugia in the Mediterranean region and underline the importance of Provence, Crimea and Crete as such refugia. Crete even might be an area of old endemism. The Atlanto- and the Ponto-Mediterranean regions are more strongly structured than assumed in classical biogeography. Mediterranean assemblages are mostly composed of non-flying species, root feeders and species with small distributions not found outside their glacial refugia. Tree feeders left their glacial retreats with their host plants. These range dynamics result in biogeographic structures with several dispersal barriers and filters composed of mountains, sea straits and climatic conditions.     

Evolution and history of the western Palaearctic avifauna

Recent data accumulated from fields as varied as avian palaeontology, palaeobotany, historical biogeography and molecular phylogenetics provide a completely renewed picture of the origin, evolution and distribution of modern birds. Although the origin of birds is still controversial, their Tertiary history is now well known. The reconstruction of palaeoenvironments and the identification of shifts in major vegetation belts and habitats during the Pliocene–Pleistocene epochs have added to these recent developments. Together they provide a new perspective on speciation and extinction rates since the late Pliocene and the establishment of modern avifaunas in the western Palaearctic.     

The tick Ixodes ricinus: distribution and climate preferences in the western Palaearctic

In this study, multivariate spatial clustering on monthly normalized difference vegetation index (NDVI) maps is used to classify ecological regions over the western Palaearctic. This classification is then used to delineate the distribution and climate preferences of populations (clades) of the tick Ixodes ricinus L. (Acari: Ixodidae) from a geographically extensive dataset of tick records and a gridded 2.5-km resolution climate dataset. Using monthly layers of the NDVI, regions of similar ecological attributes were defined and nine populations with significant differences in critical climate parameters (P< 0.005) were detected. Grouping of tick records according to other categories, such as political divisions, a 4 degrees x 4 degrees grid overlying the study area, or the CORINE) and USGS) vegetation classification schemes did not provided significantly separated populations (P = 0.094-0.304). Factor analysis and hierarchical tree clustering provided an ecological overview of these tick clades: two Mediterranean and one Scandinavian (western) clades are clearly separated from a node that includes clades of different parts of central Europe and the British Isles, with contrasting affinities between the different clades. The capture records of these ecologically separated clades produce a clear bias when bioclimate envelope modelling is applied to the mapping of habitat suitability for the tick in the western Palaearctic. The best-performing methods (Cohen's kappa = 0.834-0.912) use partial models developed with data from each ecoregion, which are then overlapped over the region of study. It is concluded that the use of ecologically derived ecoregions is an objective step in assessing the presence of ecologically different clades, and provides a guide in the development of data partitioning for habitat suitability modelling.     

Revision of the western Palaearctic Mesoleptus (Hymenoptera: Ichneumonidae)

The western Palaearctic species of the genus Mesoleptus Gravenhorst 1829 are redescribed and keys are given for their identification. Also a key for the identification of the three stilpnine genera (Atractodes, Mesoleptus, and Stilpnus) is given and the biology of the genus is discussed shortly. The following species are described as new: Mesoleptus hispanicus n. sp., M. sawoniewiczi n. sp. and M. tunisiensis n. sp. The male of Mesoleptus tobiasi Jonaitis is described for the first time. New combinations is M. incessor (Haliday). New synonyms number 143 and 34 lectotypes are chosen.     

Diversity patterns of eucalypt canopy arthropods in eastern and western Australia

1. As part of a larger study on canopy arthropods and birds, a 1‐year chemical knockdown study was carried out in one Western Australian forest, where jarrah Eucalyptus marginata and marri E. (Corymbia) calophylla were sampled, and one eastern Australian (New South Wales) forest, where narrow‐leaved ironbark E. crebra and grey box E. moluccana were sampled. 2. Ten trees of each species were sampled during each of the four seasons and the arthropods were sorted to morphospecies level. This paper documents the foliage‐associated component of arboreal arthropod communities and compares arthropod species richness within orders and families, between tree species, and between the two forest types. 3. Hymenoptera, Coleoptera, Diptera, and Araneae were the richest in species. Nine hundred and seventy‐six species in 173 families were found in the eastern Australian forest, while 687 species in 176 families were found in the western Australian forest. Only 53% of families were common to both forests, but almost half the families recorded were represented by fewer than five species. Species overlap between tree species in each region was 40–53%. 4. Analysis using nonparametric bootstrapping procedures showed that sampling of foliage was comprehensive and that only 4–9% more species would be expected with more intensive sampling of the canopy. Absolute richness, as well as differences between tree species and regions, therefore appear to be real and not the result of sampling errors. As a consequence, arthropod species richness in Australian eucalypt forests is shown to be substantially greater than previous estimates.     

柴达木盆地中西部土壤中暗色丝孢菌群落多样性分析

从柴达木盆地中西部采集土样59份,涵盖的生态类型有:沙漠、戈壁、湿地、小镇-绿洲等。分离获得暗色丝孢菌108株,经鉴定分属于15属。利用种群优势度、Shannon-Wiener多样性指数、物种均匀度、生态位宽度四项指数,对柴达木盆地中西部不同生境土壤中的有关暗色丝孢菌物种(属级)进行物种多样性分析。结果表明,该地区土壤中暗色丝孢菌的物种优势度存在明显差异:沙漠生境中,链格孢属Alternaria和细基格孢属Ulocladium真菌优势度较高;戈壁生境中,单格孢属Monodictys真菌的优势度最高;湿地和小镇-绿洲生境中,则分别以瓶霉属Phialophora和枝孢属Cladosporium真菌占优势。在小镇-绿洲生境中,土壤暗色丝孢菌的Shannon-Wiener多样性指数最高,均匀度较低;而在沙漠和戈壁生境中多样性指数明显较低,而物种的均匀度较高。在上述四类生境中,链格孢属Alternaria和细基格孢属Ulocladium真菌具有较宽的生态位,为广适性物种;而平脐蠕孢属Bipolaris、卷旋孢属Cirrenaria、弯孢属Curvularia、矛束霉属Doratomyces、粘束孢属Graphium、漆斑霉属Myrothecium、齿梗孢属Scolecobasidium、帚霉属Scopulariopsis、节隔孢属Scytalidium和葡萄穂霉属Stachybotrys10个属真菌的生态位较窄,为狭适性物种。     

Widespread unidirectional transfer of mitochondrial DNA: a case in western Palaearctic water frogs

Interspecies transfer of mitochondrial (mt) DNA is a common phenomenon in plants, invertebrates and vertebrates, normally linked with hybridization of closely related species in zones of sympatry or parapatry. In central Europe, in an area north of 48 degrees N latitude and between 8 degrees and 22 degrees E longitude, western Palaearctic water frogs show massive unidirectional introgression of mtDNA: 33.7% of 407 Rana ridibunda possessed mtDNA specific for Rana lessonae. By contrast, no R. lessonae with R. ridibunda mtDNA was observed. That R. ridibunda with introgressed mitochondrial genomes were found exclusively within the range of the hybrid Rana esculenta and that most hybrids had lessonae mtDNA (90.4% of 335 individuals investigated) is evidence that R. esculenta serves as a vehicle for transfer of lessonae mtDNA into R. ridibunda. Such introgression has occurred several times independently. The abundance and wide distribution of individuals with introgressed mitochondrial genomes show that R. lessonae mt genomes work successfully in a R. ridibunda chromosomal background despite their high sequence divergence from R. ridibunda mtDNAs (14.2-15.2% in the ND2/ND3 genes). Greater effectiveness of enzymes encoded by R. lessonae mtDNA may be advantageous to individuals of R. ridibunda and probably R. esculenta in the northern parts of their ranges.     

Diversity and seasonal patterns of ticks parasitizing wild birds in western Portugal

The diversity and abundance of questing ticks and ticks parasitizing birds was assessed during 1?year in two recreational forests in western Portugal, a suburban forest and an enclosed game area. The aim of this study was to assess the distribution and seasonality of tick species and to understand the role of bird species as hosts for ticks. Ixodes ricinus was the most abundant questing tick collected in the enclosed game area, whereas in the suburban forest, only three ticks were collected by blanket dragging. Tick species parasitizing birds included I. ricinus, I. frontalis, I. arboricola, I. acuminatus, Haemaphysalis punctata, Hyalomma marginatum and H. lusitanicum. This is the first record of I. arboricola in Portugal. Tick prevalence and intensity of infestation differed between study areas and was higher in birds from the game area where a large population of deer and wild boar may support tick populations. Ground and shrub dwelling bird species such as Turdus merula, Erithacus rubecula and Sylvia melanocephala were the most heavily parasitized by ticks, but the importance of different bird species as hosts of larvae and nymphs of I. ricinus and I. frontalis differed. Therefore, different bird species may contribute differently for tick population maintenance.     

Evolution,biogeography and systematics of the western Palaearctic Zamenis ratsnakes

The phylogenetic relationships between western Palaearctic Zamenis and Rhinechis ratsnakes have been troubled, with recent estimates based on the supermatrix approach questioning their monophyly and providing contradictory results. In this study, we generated a comprehensive molecular data set for Zamenis and closely related ratsnakes to assess their phylogenetic and systematic relationships and infer their spatial and temporal modes of diversification. We obtained a fully resolved and well‐supported phylogeny, which is consistent across markers, taxon‐sets and phylogenetic methods. The close phylogenetic relationship between Rhinechis and Zamenis is well‐established. However, the early branching pattern within this clade, and the position of R. scalaris and Z. hohenackeri, remains poorly supported. The Persian ratsnake Z. persicus is sister to the Mediterranean species Z. situla, Z. longissimus and Z. lineatus, of which Z. situla is sister to a clade containing the latter two species. These results are consistent with a recent phylogenomic study on ratsnakes based on hundreds of loci. Whereas, topological tests based on our data and evidence from such phylogenomic study strongly rejected previous phylogenetic estimates based on the supermatrix approach and demonstrate that these “mega‐phylogenies”, with hundreds of taxa and high levels of missing data, have recovered inconsistent relationships with spurious nodal support. Biogeographical and molecular dating analyses suggest an origin of the ancestor of Rhinechis and Zamenis in the Aegean region with early cladogenesis during the Late Miocene associated with the Aegean arch formation and support a scenario of east‐to‐west diversification. Finally, while we have little morphological and phylogenetic evidence for the distinctiveness between Rhinechis and Zamenis, a classification of them in a single genus, and the designation of Zamenis scalaris (Schinz, 1822), reflects better their evolutionary relationships.     

Topographic patterns of odorant receptor expression in mammals: a comparative study

In a comparative study, molecular probes for various odorant receptor subtypes were employed in in situ hybridization experiments on tissue sections through the nose from different mammalian species. OR37 reactive neurons were found exclusively in the rodent species, where they were clustered in very similar position within the nasal cavities; an OR37-related receptor subtype was not detectable in the rabbit. All other subtypes tested, hybridized across species borders to neurons that were distributed within distinct zones of the olfactory epithelium. Most receptor types were found in the same zone in all species; however, a few subtypes which are expressed in the medial zone in rat were found in the dorsal zone in guinea pig.     

中印度洋与南海西部表层海水细菌多样性

细菌在海洋生物地球化学循环中发挥着重要作用。为更好地了解海洋细菌的特征及其在海洋环境中的潜在作用, 本文利用纯培养与16S rRNA基因高通量测序技术对中印度洋与南海西部海域表层海水细菌多样性进行研究。纯培养结果表明, 自中印度洋与南海西部表层海水中共分离275株可培养海洋细菌, 隶属于4门49属75种。变形菌门是绝对优势类群(占总株数的68.7%), 其次是放线菌门(21.5%)、拟杆菌门(9.1%)和厚壁菌门(0.7%)。在属水平, 微杆菌属(Microbacterium)与弧菌属(Vibrio)是主要的优势属, 共占总株数的30.0%。在3种分离培养基中, 自1/10 × 2216E培养基中分离细菌的数目与种类最多(89株, 30属); 分离菌株中的细菌菌株有7、9与3个属分别仅在2216E、1/10 × 2216E及葡萄糖甘露糖(glucose-mannose, GM)培养基中生长。此外, 共分离培养出50株细菌(26种)可能代表潜在新分类单元。高通量测序结果显示, 中印度洋和南海西部表层海水中共有23个门531个属。优势门类为变形菌门(72.2%)和拟杆菌门(15.3%), 优势属为嗜冷杆菌属(Psychrobacter, 24.4%)、盐单胞菌属(Halomonas, 16.3%)和亚硫酸杆菌属(Sulfitobacter, 13.9%)。此外, 中印度洋表层海水细菌Shannon-Wiener指数与Pielou均匀度指数显著高于南海西部(P < 0.05), 且细菌群落结构显著不同(P < 0.05)。综合纯培养与原位细菌数据得出, 中印度洋与南海西部海洋细菌具有丰富的多样性, 具有进一步开发研究的价值。     

Silurian-Devonian miospores from the western and central Algeria

The age of Rock Units B1 and B2 of the Middle Silurian-Lower Devonian of Sahara (Algeria) is assessed and confirmed as late Homerian to ?earliest Lochkovian on the basis of moderately well preserved miospore assemblages. The data upon which this age assessment is provided by recent palynological studies in the Cantabrian Mountains (NW Spain), the type Wenlock area, Shropshire (England), south and south-west Wales, the Midland Valley of Scotland and the Ghadames Basin, Libya. Quantitative study shows that cryptospores decrease in number and variety upwards, laevigate miospores are prevalent and the representatives of the rugulate, crassitate genus Scylaspora are dominant. The occurrence and range of these species as well as other miospore taxa recorded during this study provide the basis for recognizing three miospore assemblage and one interval biozones, namely Scylaspora vetusta-Scylaspora kozlica, Chelinospora sanpetrensis-Cymbosporites triangulatus, Chelinospora hemiesferica and Scylaspopra radiata-Apiculiretusispora synoria. Of these biozones, two assemblage biozones are proposed as new. Core samples of Rock Unit B1 from borehole NGS-1 of the Triassic Province contain the oldest two miospore assemblage biozones. Rock Unit B2 from the boreholes GMD-2, ISS-1 (Tidikelt Plateau) and NGS-1 (Triassic Province) comprise the youngest two miospore biozones. The assemblage and interval biozones allow inter-regional correlation with latest Middle Silurian to probably earliest Devonian strata. The inadequacy of coverage of core samples result in the absence of critical palynological evidence, to determine the exact position of the base of the Ludlow, Pridoli and Lochkovian. Comparison with the zonal and sub-zonal divisions of Mid-Palaeozoic sequences from other parts of the world shows crucial differences in the distribution of the spore flora within Gondwanan and Euramerican regions during Pridoli and early Lochkovian. Six new miospore species namely Retusotriletes delicatus nov. sp., Scylaspora cymba nov. sp., S. distincta nov. sp., S. radiata nov. sp., S. undulata nov. sp. and Cymbosporites triangulatus nov. sp. are described. Three more possibly new miospore forms are described and illustrated but not specifically named.     

Broad‐scale geographic patterns in body size and hind wing development of western Palaearctic carabid beetles(Coleoptera: Carabidae)

Research into large‐scale ecological rules has a long tradition but has received increasing attention over the last two decades. Whereas environmental, especially climatic, influences on the geographic distribution of species traits such as body size are well understood in mammals and birds, our knowledge of the determinants and mechanisms which shape spatial patterns in invertebrate traits is still limited. This study analyzes macroecological patterns in two traits of the highly diverse invertebrate taxon of carabid beetles: body size and hind wing development, the latter being directly linked to species’ dispersal abilities. We tested for potential impacts of environmental variables (spatial, areal, topographic and climate‐related) representing both contemporary conditions and historical processes on large‐scale patterns in the two traits. Regression models revealed hump‐shaped relationships with latitude for both traits in the categories 1) all species, 2) widespread and 3) endemic (restricted‐range) species: body size and the proportion of flightless species increased from northern towards southern Europe and then decreased towards North Africa. The shared and independent influence of environmental factors was analyzed by variation partitioning. While contemporary environmental productivity and stability (represented by measures of ambient energy and water energy balance) had strong positive relationships with carabid body size, patterns in hind wing development were most notably influenced by topography (elevation range). Regions with high elevation range and low historical climate variability (since the last ice age), which likely offer long‐term stable habitats (i.e. glacial refugia), coincide with regions with high proportions of flightless species. Thus geographic patterns in carabid traits tend to be formed not only by recent climate but also by dispersal and historical climate and processes (i.e. glaciations and postglacial colonization).     

Diversity patterns of wet meadows along geochemical gradients in central Spain

Four measures of biodiversity (species number per site, total species number, mean similarity and mosaic diversity) and their relationships with soil chemical composition were studied in vascular plant communities in groundwater discharge ecosystems of central Spain. Species richness decreased with increasing salinity, alkalinity and halite concentration. Species richness was apparently controlled more by soil toxicity than by soil nutrient levels, although a positive correlation of Ca²⁺ with species richness was found after accounting for the effects of toxic compounds. All relationships were strictly monotonic. Six community types were identified based on their soil chemical characteristics: glycophyte, subglycophyte, tolerant, subalkalinophyte, alkalinophyte, and halocalcicole communities. Within community types, species richness showed very few significant relationships with soil characteristics. Mean species richness was lowest in the environmentally stressful communities. Total species richness was greatest in the ecotonal community type. Mean similarity, a measure of among-community diversity, and mosaic diversity, a measure of landscape complexity, differed among community types. Mean similarity was smaller (higher diversity) in species-poor community types, while mosaic diversity was greatest (greater complexity) in species-rich community types. The halocalcicole community type was richest in rare species.     

Syntopic frogs reveal different patterns of interaction with the landscape: A comparative landscape genetic study of Pelophylax nigromaculatus and Fejervarya limnocharis from central China

Amphibians are often considered excellent environmental indicator species. Natural and man‐made landscape features are known to form effective genetic barriers to amphibian populations; however, amphibians with different characteristics may have different species–landscape interaction patterns. We conducted a comparative landscape genetic analysis of two closely related syntopic frog species from central China, Pelophylax nigromaculatus (PN) and Fejervarya limnocharis (FL). These two species differ in several key life history traits; PN has a larger body size and larger clutch size, and reaches sexual maturity later than FL. Microsatellite DNA data were collected and analyzed using conventional (F_ST, isolation by distance (IBD), AMOVA) and recently developed (Bayesian assignment test, isolation by resistance) landscape genetic methods. As predicted, a higher level of population structure in FL (F_ST′ = 0.401) than in PN (F_ST′ = 0.354) was detected, in addition to FL displaying strong IBD patterns (r = .861) unlike PN (r = .073). A general north–south break in FL populations was detected, consistent with the IBD pattern, while PN exhibited clustering of northern‐ and southern‐most populations, suggestive of altered dispersal patterns. Species‐specific resistant landscape features were also identified, with roads and land cover the main cause of resistance to FL, and elevation the main influence on PN. These different species–landscape interactions can be explained mostly by their life history traits, revealing that closely related and ecologically similar species have different responses to the same landscape features. Comparative landscape genetic studies are important in detecting such differences and refining generalizations about amphibians in monitoring environmental changes.