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Abstract The Scarlet Pygmy Nannophya pygmaea Rambur, 1842 (Odonata: Libellulidae), the smallest described dragonfly species, is found across the Pacific coast and along the island chains of eastern Asia. Previous research has questioned whether N. pygmaea is potentially a complex of multiple species. Past studies have proposed a new species, N. koreana, based on mitochondrial genetic data, but the N. pygmaea complex remains unresolved. Using increased taxon sampling, we assessed genetic differentiation across populations and reconstructed evolutionary relationships of the N. pygmaea complex. From 141 COI-5P sequences, we calculated genetic structure through estimation of pairwise FST values among 10 populations and constructed a haplotype network to determine genetic differentiation, which revealed extremely high differentiation between northern populations (Japan, South Korea, China, and Laos) and southern peninsula/island chain populations (Malaysia, Singapore, Indonesia, and Vietnam). Species distribution models (SDMs) showed large stretches of less suitable habitat between regions populated by N. pygmaea. A lack of gene flow and geographical isolation between the clades supports these highly differentiated populations being described as separate species. Additionally, our SDMs explored the prevalence of present suitable habitats and how habitat suitability may shift between now and 2070. Our paleodistribution modeling provides insight into possible land migration routes that would allow N. pygmaea, as a weak flyer, to have dispersed to its present-day distribution. Ordination analysis of niche divergence between the northern and southern clades found no significant levels of niche differentiation or similarity between the 2 clades. 

Abstract Climate change is one of the main drivers of a global insect decline. Stoneflies (Insecta: Plecoptera) have one of the highest local extinction rates among insects, in part due to their requirements for cold, highly oxygenated, unpolluted water. Investigating the population structure of stonefly species is integral to their conservation as it can identify populations at risk of localized extinction.In this study, we extracted DNA fromNemoura arctica(Esben‐Petersen, 1910),Nemoura cinerea(Retzius, 1783) andNemurella pictetii(Klapálek, 1900) specimens collected across Arctic Alaska, Sweden and Finland. We sequenced the mitochondrialCOIgene and the nuclear28Sgene of 96 specimens from 9 locations and constructed haplotype networks for these three species by combining our sequences with publicly available sequences of circumboreal stoneflies from the Barcode of Life Database (BOLD) and the National Center for Biotechnology Information (NCBI) GenBank.Haplotype networks suggest thatN. arcticaandN. cinereahave higherCOIgenetic diversity thanN. pictetii, with potential evidence for the description of new species.We modeled past, present and future habitat suitability using species distribution models (SDMs) in the program Wallace v2.1.3. Our models predict that all three species will lose most or all of their current suitable habitat by 2070, no matter the climate scenario. 

Abstract Scientific and public interest in the global status of insects has surged recently; however, understanding the relative importance of different stressors and their interconnections remains a crucial problem. We use a meta-synthetic approach to integrate recent hypotheses about insect stressors and responses into a network containing 3385 edges and 108 nodes. The network is highly interconnected, with agricultural intensification most often identified as a root cause. Habitat-related variables are highly connected and appear to be underdiscussed relative to other stressors. We also identify biases and gaps in the recent literature, especially those generated from a focus on economically important and other popular insects, especially pollinators, at the expense of non-pollinating and less charismatic insects. In addition to serving as a case study for how meta-synthesis can map a conceptual landscape, our results identify many important gaps where future meta-analyses will offer critical insights into understanding and mitigating insect biodiversity loss. 

Nannothemis bella Uhler, 1857 (Odonata: Libellulidae), the smallest dragonflyin North America, inhabit bogs and sedge fens across their distribution, spanning fromQuebec (Canada) south to Florida and west to Minnesota and Louisiana (USA). While commonin the northern part of their range, N. bella is of conservation concern in the southernpopulations where they are disjunct and rare. Little work has been done on the ecologyand geographic conservation of this species. To fill this knowledge gap, we constructedspecies distribution models (SDMs) to analyze the spatial distribution and climatic nicheof N. bella, define factors in habitat suitability and estimate potential niche shifts underclimate change and inform conservation efforts. Our present-day SDMs indicate the dominantenvironmental elements determining habitat suitability include the proportion of siltin soil, temperature seasonality, percentage of clay and coarse components in soil, and soilclass. Our paleodistribution models show a southern distribution within the last glacialmaximum, with a shift northward 8,326 to 4,200 years ago. Our projected SDMs for 2050under RCP 2.6 and RCP 8.5 predict a significant decrease in habitat suitability throughoutthe entire range of N. bella. As such, N. bella is a species of conservation concern andconservation measures are imperative for its continued existence as a much-needed bioindicatorfor these freshwater ecosystems. Additionally, this ecological knowledge providesthe foundation for identifying population sites from which to collect N. bella for futurepopulation genetic studies. 

Abstract Mountains and islands provide an opportunity for studying the biogeography of diversification and population fragmentation. Aotearoa (New Zealand) is an excellent location to investigate both phenomena due to alpine emergence and oceanic separation. While it would be expected that separation across oceanic and elevation gradients are major barriers to gene flow in animals, including aquatic insects, such hypotheses have not been thoroughly tested in these taxa. By integrating population genomic from sub-genomic Anchored-Hybrid Enrichment sequencing, ecological niche modeling, and morphological analyses from scanning-electron microscopy, we show that tectonic uplift and oceanic vicariance are implicated in speciation and population structure in Kapokapowai (Uropetala) dragonflies. Although Te Moana o Raukawa (Cook Strait), is likely responsible for some of the genetic structure observed, speciation has not yet occurred in populations separated by the strait. We find that the altitudinal gradient across Kā Tiritiri-o-te-Moana (the Southern Alps) is not impervious, but it significantly restricts gene flow between the aforementioned species. Our data support the hypothesis of an active colonization of Kā Tiritiri-o-te-Moana by the ancestral population of Kapokapowai, followed by a recolonization of the lowlands. These findings provide key foundations for the study of lineages endemic to Aotearoa. 

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. 

Neurocordulia, commonly called shadowdragons, are crepuscular dragonflies, flying mainly at dusk. The genus comprises seven species, which occur across the eastern part of Canada and the United States. Here, we used targeted enrichment probes to sequence ~1000 loci for all specimens of each species, allowing for the first phylogenetic assessment of the genus. Additionally, we collected individuals of N. yamaskanensis from a population in Ontario, Canada, and used whole genome resequencing to estimate population structure. Beyond broadly reconstructing the phylogeny of Neurocordulia, we provided a comprehensive bibliography review of past research on the genus, a key to the species, and distribution models for each species.