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Aim: New areas are often simultaneously invaded by closely related alien species; however, between‐species differences in the course of their invasive spreading due to diverse ecological preferences have rarely been investigated. Here, we aim to study the species‐specific spatio‐temporal invasion patterns of Solidago canadensis and S. gigantea. Location: Slovakia—the Western Carpathian and adjacent Pannonian regions. Taxon: Invasive alien Solidago canadensis and S. gigantea. Methods: Our study was based on revised herbarium specimens, a recent field survey which included gathering abundance and habitat data, and environmental data from GIS layers. We characterised the environmental niche differentiation between S. canadensis and S. gigantea. Generalised additive models were then used to identify the key drivers of the species' occurrences and to assess their potential current and future distributions. Results: Both species began to spread in Slovakia in the 1850s; in the first 100 years, the number of S. gigantea sites increased exponentially, while that of S. canadensis remained low. Currently, S. canadensis is more widespread in the region. The species have similar habitat preferences. Their environmental niches overlap, but are not identical. The core distribution of S. canadensis is in foothills and valleys that experience lower annual mean temperatures, while that of S. gigantea is in lowlands with higher annual mean temperatures. A large part of their potential distribution areas seems to be already invaded. Possible future climate change could stimulate the spreading of S. canadensis into higher altitudes and S. gigantea farther into lowlands and Carpathian foothills. Main conclusions: The studied invasive Solidago species differed considerably in the early stages of invasion. Their environmental niches, current realised and potential distribution patterns are different. In the studied region, further spreading, with an increase in the number and size of populations, is likely unless effective measures are undertaken. [ABSTRACT FROM AUTHOR]

Aim: While environmental conditions are reported as important determinants of cytotype distribution patterns in some mixed‐ploidy plant species, in others they seem to play no role. One reason for such inconsistency might be how and at what spatial scale the ecology of different cytotypes is compared. To address this issue, we adopted several complementary approaches to assess ecological requirements of cytotypes in a single species across wide‐range of spatial scales. Location: Europe. Taxon: Tripleurospermum inodorum (Asteraceae). Methods: WorldClim extracted data were used for comparing climatic niches of T. inodorum diploids and tetraploids at continental and subcontinental scales and for predicting climatic suitability of habitats in Europe. Within the contact zone of cytotypes, at the regional scale, ecological preferences of cytotypes were assessed independently in three regions. Habitat types and ecological indicators inferred from species composition of vegetation in both uniform‐ploidy and mixed‐ploidy populations were used for ecological niche reconstructions. Results: The two cytotypes differed in their climatic niches. However, due to considerable niche overlap, diploids and tetraploids were predicted to co‐occur in an extensive contact zone in Europe. Within the contact zone, cytotypes had identical ecological preferences but varied in their frequency at particular habitat types. The ecological niches of mixed‐ploidy and uniform‐ploidy populations were undistinguishable. Main conclusions: Cytotype distribution patterns may be shaped by multiple environmental forces, each operating at a different spatial scale. In T. inodorum, climate is an important driver of cytotype distribution patterns at continental scale, however, at finer scales within the contact zone, the founder effect and non‐random migration patterns caused by human activities seem to be more important than environmental heterogeneity. The use of independent replicates and/or across‐scale comparisons can significantly improve the performance of ecological niche assessments. [ABSTRACT FROM AUTHOR]

Aim Shells of fossil molluscs are important for palaeoecological reconstructions. However, the habitat requirements of snail species typical of central European full-glacial loess sediments are poorly known because most of them became very rare or extinct in Europe. The recent discovery of an almost complete extant assemblage of such species in mountainous regions of central Asia enables more precise characterization of their habitats, which may significantly improve reconstructions of Pleistocene environments. Location Altai Mountains, Russia. Methods Terrestrial snail assemblages, vegetation composition and selected environmental variables were recorded at 118 sites along a gradient of climatic continentality in the Russian Altai. Habitat characteristics of sites where species typical of the full-glacial period occurred were described using a classification tree. Results Seven of the eight species that are typical of central European full-glacial loess sediments were found in the study area. They were confined to cool areas with January mean temperatures below −17 °C, but occurred mainly in sheltered habitats with a warmer microclimate, such as scrub or open woodland. Pupilla loessica and Vallonia tenuilabris had the broadest habitat range, occurring from woodland to dry steppe. Unexpectedly, Columella columella, Pupilla alpicola, Vertigo genesii, V. parcedentata and V. pseudosubstriata were found mainly in wooded fens and shrubby tundra rather than in open steppe. Most of these seven species were recorded in base-rich wooded fens. Very dry open steppe habitats usually supported no snails. Main conclusions Habitat ranges of the studied snails in the Altai indicate that the full-glacial landscapes of central European lowlands that harboured these species were not completely dominated by open and dry loess steppe. Most probably they contained a significant component of shrubby vegetation, patches of wet habitats, and probably also areas of woodland at sites with a favourable mesoclimate. [ABSTRACT FROM AUTHOR]

Aims To study the community structure and habitat preferences of the Epsilonematidae and Draconematidae in coral degradation zones. To assess the contribution of different localities and microhabitats to meiobenthic diversity in such ecosystems. To discuss dispersive capacities and the occurrence of cryptic species in meiobenthic organisms. Location Porcupine Seabight (north-east Atlantic Ocean; continental slope) and a transect along the Kenyan coast (Indian Ocean; shallow lagoon). Methods In the north-east Atlantic, dead coral fragments, sponge skeletons and sediment were collected with a boxcorer. Along the Kenyan coast, dead coral fragments and coral gravel were collected during snorkelling and skin diving. Only nematodes belonging to the families Epsilonematidae and Draconematidae were considered. Community structure was analysed using multivariate techniques. Biodiversity was represented via rarefaction curves. Additive partitioning of species diversity was conducted. Turnover between microhabitats within locations and between locations within microhabitats were compared in a ternary plot. Results Twelve epsilonematid and five draconematid species were found in the Porcupine Seabight. In Kenya, 39 epsilonematid and 20 draconematid species were distinguished. Three species were found at both sampling locations. A table with the known distribution of all currently described species encountered in our study area is provided. At both sampling locations, the communities on coral fragments were significantly different from those in the other microhabitats, and were most diverse. In Kenya, species richness was mainly determined by local diversity and by turnover between localities. The contribution of β-diversity decreased when abundance data were analysed. Turnover between microhabitats and between coral samples from different localities was higher than turnover between locations for gravel samples. Main conclusions Coral fragments were recognized as favourable substrata for typically epifaunal nematodes. Species-specific habitat preferences were explained by finely tuned morphological adaptations. Our results suggest that cosmopolitan species could well be cryptic species, and this explanation for the existence of morphologically identical nematodes in geographically distant areas is weighed up against other plausible explanations. Coral degradation zones are an important source for new species of Epsilonematidae and Draconematidae. The addition of sampling locations contributed to the total number of species, although the added species were generally rare. [ABSTRACT FROM AUTHOR]

Aim Three species of primitive spiders of the genus Atypus occur in European xerothermic habitats, where they live in burrows. The aim of this study is to explain their distribution by investigating environmental variables at sites where they occur in central Europe. Location Over 50 sites in central Europe, Czech Republic. Methods Data on climatic, edaphic and vegetational parameters were collected from more than 50 sites. Phytocenological data were processed using Ellenberg's indicator values. Results Atypus muralis was found to occur almost exclusively in dry grassland (Festucion valesiacae), exposed to a continental microclimate. Atypus affinis usually occurred in dry sparse forests (Genisto germanicae–Quercion) that provide an Atlantic microclimate. Atypus piceus occurred in dry grassland (Bromion erecti) or forest fringes (Geranion sanguinei) characterized by an intermediate microclimate. Atypus piceus and A. muralis were restricted to agglutinate calcareous soils. Main conclusions Our results show that Atypus species colonized sites with different continentality in central Europe. These differences correspond to differences among their probable glacial refugia. Atypus muralis and A. piceus occur in habitats with a markedly continental climate, and are restricted to calcareous agglutinate soils that more efficiently buffer temperature and humidity extremes. Habitats of A. muralis and A. piceus are threatened by overgrowth of vegetation after a recent decline in grazing and by the decalcification of the landscape. However, habitats of A. affinis are stable in the present central European climate. [ABSTRACT FROM AUTHOR]