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Abstract The striped emeralds (SomatochloraSelys) are a Holarctic group of medium‐sized metallic green dragonflies that mainly inhabit bogs and seepages, alpine streams, lakes, channels and lowland brooks. With 42 species they are the most diverse genus within Corduliidae (Odonata: Anisoptera). Systematic, taxonomic and biogeographic resolution withinSomatochloraremains unclear, with numerous hypotheses of relatedness based on wing veins, male claspers (epiproct and paraprocts) and nymphs. Furthermore,Somatochlora borisiwas recently described as a new genus (Corduliochlora) based on 17 morphological characters, but its position with respect toSomatochlorais unclear. We present a phylogenetic reconstruction ofSomatochlorausing Anchored Hybrid Enrichment (AHE) sequences of 40/42Somatochloraspecies (includingCorduliochlora borisi). Our data recover the monophyly ofSomatochlora, withC. borisirecovered as sister to the remainingSomatochlora. We also recover three highly supported clades and one of mixed support; this lack of resolution is most likely due to incomplete lineage sorting, third‐codon position saturation based on iterative analyses run on variations of our dataset and hybridization. Furthermore, we constructed a dataset for all species based on 20 morphological characters from the literature which were used to evaluate phylogenetic groups recovered with molecular data; the data support the validity ofCorduliochloraas a genus distinct fromSomatochlora. Finally, divergence time estimation and biogeographic analysis indicateSomatochloraoriginated in the Western North Hemisphere during the Miocene, with three dispersal events to the Eastern North Hemisphere (11, 7 and 5 Ma, respectively) across the Beringian Land Bridge. 

Odonata comprise approximately 6400 species with extensive morphological and ecological diversity, specifically their colour variation, flight behaviour patterns, and breadth of ecological niches. Additionally, their phylogenetic placement within Insecta as descendants of the first winged insects make them ideal candidates for exploring evolutionary forces that have shaped diversity patterns (e.g., diversification rate shifts) as well as character evolution (e.g., flight behaviour, colour). Even though morphological and ecological traits are relatively well known for most of odonate taxa, the lack of well-supported phylogenetic hypothesis across Odonata have limited the capability of evaluating evolutionary phenomena in a comparative context. Previous studies using various taxon sampling schemes and data types (i.e. morphology, targeted locus approaches) to reconstruct odonate relationships failed to resolve several interfamilial relationships, specifically in groups with likely incomplete lineage sorting and/or introgression. Even though a recent study by Bybee et al. (2021) incorporated genomic-scale anchored hybrid enrichment (AHE) data for phylogenetic reconstruction, the relatively limited taxon sampling likely precluded resolution within the problematic groups. Our study, also targeting AHE loci, greatly expand taxon odonate genera, which resulted in 729 newly generated samples in a addition to 142 samples from Bybee et al. (2021) for a total of 831. With around 500 AHE loci, we aim to resolve historically difficult relationships and construct a robust ordinal phylogeny of Odonata, which will be used as the evolutionary framework to clarify taxonomic classifications and test evolutionary hypotheses regarding shifts in flight behaviours, colours, and diversification rates. 

More than 1.2 million distribution records were used to create species distribution models for 402 Palaearctic species of dragonflies and damselflies. On the basis of these diversity maps of total, lentic and lotic diversity for the whole of the Palaearctic (excluding China and the Himalayan region) are presented. These maps show a clear pattern of decreasing diversity longitudinally, with species numbers dropping in the eastern half of Europe and remaining low throughout a large part of Russia, then increasing again towards Russia’s Far East and Korea. There are clear differences in diversity patterns of lentic and lotic species, with lentic species being dominant in colder and more arid areas. Areas with a high diversity of species assessed as threatened on the IUCN red list are largely restricted to the Mediterranean, Southwest Asia, and Japan, with clear hotspots found in the Levant and the southern half of Japan. The diversity at species, generic, and family level is higher in the south of Japan than in areas at a similar latitude in the western Mediterranean. This is likely to be the result of the more humid climate of Japan resulting in a higher diversity of freshwater habitats and the stronger impact of the glacial periods in the Western Palaearctic in combination with the Sahara, preventing tropical African lineages dispersing northwards.