The European steppes and their biota have been hypothesized to be either young remnants of the Pleistocene steppe belt or, alternatively, to represent relicts of long-term persisting populations; both scenarios directly bear on nature conservation priorities. Here, we evaluate the conservation value of threatened disjunct steppic grassland habitats in Europe in the context of the Eurasian steppe biome. We use genomic data and ecological niche modelling to assess pre-defined, biome-specific criteria for three plant and three arthropod species. We show that the evolutionary history of Eurasian steppe biota is strikingly congruent across species. The biota of European steppe outposts were long-term isolated from the Asian steppes, and European steppes emerged as disproportionally conservation relevant, harbouring regionally endemic genetic lineages, large genetic diversity, and a mosaic of stable refugia. We emphasize that conserving what is left of Europe's steppes is crucial for conserving the biological diversity of the entire Eurasian steppe biome.

Aims Understanding fine‐grain diversity patterns across large spatial extents is fundamental for macroecological research and biodiversity conservation. Using the GrassPlot database, we provide benchmarks of fine‐grain richness values of Palaearctic open habitats for vascular plants, bryophytes, lichens and complete vegetation (i.e., the sum of the former three groups). Location Palaearctic biogeographic realm. Methods We used 126,524 plots of eight standard grain sizes from the GrassPlot database: 0.0001, 0.001, 0.01, 0.1, 1, 10, 100 and 1,000 m2 and calculated the mean richness and standard deviations, as well as maximum, minimum, median, and first and third quartiles for each combination of grain size, taxonomic group, biome, region, vegetation type and phytosociological class. Results Patterns of plant diversity in vegetation types and biomes differ across grain sizes and taxonomic groups. Overall, secondary (mostly semi‐natural) grasslands and natural grasslands are the richest vegetation type. The open‐access file ”GrassPlot Diversity Benchmarks” and the web tool “GrassPlot Diversity Explorer” are now available online (https://edgg.org/databases/GrasslandDiversityExplorer) and provide more insights into species richness patterns in the Palaearctic open habitats. Conclusions The GrassPlot Diversity Benchmarks provide high‐quality data on species richness in open habitat types across the Palaearctic. These benchmark data can be used in vegetation ecology, macroecology, biodiversity conservation and data quality checking. While the amount of data in the underlying GrassPlot database and their spatial coverage are smaller than in other extensive vegetation‐plot databases, species recordings in GrassPlot are on average more complete, making it a valuable complementary data source in macroecology.

Kraj ı cek, M., Fott, J., Miracle, M.R., Ventura, M., Sommaruga, R., Kirschner, P., Cern y, M. (2015). The genus Cyclops (Copepoda, Cyclopoida) in Europe. -Zoologica Scripta, 45, 671-682. Although copepods of the genus Cyclops are among the most common and dominant plankton taxa of lakes in the northern temperate zone, their taxonomy is still unclear. We analysed an extensive array of Cyclops populations from Europe by means of molecular methods and evaluated morphological characters. Altogether, 68 populations of Cyclops species were sampled, assigned to morphospecies and sequenced for the 12S rRNA gene. Selected populations of each morphospecies were additionally sequenced for three mitochondrial (16S rRNA, cytochrome b, COI) and two nuclear genes (18S rRNA, ITS1) and analysed for micromorphological traits. Our analysis revealed fifteen lineages that can be regarded as separate species. Thirteen of these match currently accepted species, while the remaining two lineages were distinct from the other described species. Thus, their taxonomic status is open to further studies. Besides taxonomy, our study gives new insights into the ecology, distribution and phylogenetic relationships of these species. Finally, a set of morphological traits was selected to facilitate identification.

Glacial refugia of alpine and subnival biota have been intensively studied in the European Alps but the fate of forests and their understory species in that area remains largely unclear. In order to fill this gap, we aimed at disentangling the spatiotemporal diversification of disjunctly distributed black hellebore Helleborus niger (Ranunculaceae). We applied a set of phylogeographic analyses based on restriction-site associated DNA sequencing (RADseq) data and plastid DNA sequences to a range-wide sampling of populations. These analyses were supplemented with species distribution models generated for the present and the Last Glacial Maximum (LGM). We used exploratory analyses to delimit genomically coherent groups and then employed demographic modeling to reconstruct the history of these groups. We uncovered a deep split between two major genetic groups with western and eastern distribution within the Southern Limestone Alps, likely reflecting divergent evolution since the mid-Pleistocene in two glacial refugia situated along the unglaciated southern margin of the Alps. Long-term presence in the Southern Limestone Alps is also supported by high numbers of private alleles, elevated levels of nucleotide diversity and the species’ modeled distribution at the LGM. The deep genetic divergence, however, is not reflected in leaf shape variation, suggesting that the morphological discrimination of genetically divergent entities within H. niger is questionable. At a shallower level, populations from the Northern Limestone Alps are differentiated from those in the Southern Limestone Alps in both RADseq and plastid DNA data sets, reflecting the North-South disjunction within the Eastern Alps. The underlying split was dated to ca. 0.1 mya, which is well before the LGM. In the same line, explicit tests of demographic models consistently rejected the hypothesis that the partial distribution area in the Northern Limestone Alps is the result of postglacial colonization. Taken together, our results strongly support that forest understory species such as H. niger have survived the LGM in refugia situated along the southern, but also along the northern or northeastern periphery of the Alps. Being a slow migrator, the species has likely survived repeated glacial-interglacial circles in distributional stasis while the composition of the tree canopy changed in the meanwhile.

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