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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 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. 

ABSTRACT Although patterns of population genomic variation are well‐studied in animals, there remains room for studies that focus on non‐model taxa with unique biologies. Here we characterise and attempt to explain such patterns in mygalomorph spiders, which are generally sedentary, often occur as spatially clustered demes and show remarkable longevity. Genome‐wide single nucleotide polymorphism (SNP) data were collected for 500 individuals across a phylogenetically representative sample of taxa. We inferred genetic populations within focal taxa using a phylogenetically informed clustering approach, and characterised patterns of diversity and differentiation within‐ and among these genetic populations, respectively. Using phylogenetic comparative methods we asked whether geographical range sizes and ecomorphological variables (behavioural niche and body size) significantly explain patterns of diversity and differentiation. Specifically, we predicted higher genetic diversity in genetic populations with larger geographical ranges, and in small‐bodied taxa. We also predicted greater genetic differentiation in small‐bodied taxa, and in burrowing taxa. We recovered several significant predictors of genetic diversity, but not genetic differentiation. However, we found generally high differentiation across genetic populations for all focal taxa, and a consistent signal for isolation‐by‐distance irrespective of behavioural niche or body size. We hypothesise that high population genetic structuring, likely reflecting combined dispersal limitation and microhabitat specificity, is a shared trait for all mygalomorphs. Few studies have found ubiquitous genetic structuring for an entire ancient and species‐rich animal clade. 

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. 

Abstract Odonata is a midsized insect order (~6420 species) containing 3 suborders: Anisoptera (dragonflies, 3,120 species), Zygoptera (damselflies, ~3,297 species), and the intermediate Anisozygoptera (~3 species). In this review of the suborder Zygoptera, we provide a brief overview of their biology, ecology, and natural history. We also review the current state of their systematics and phylogenetics, highlighting remaining higher-level classification (eg family, superfamily) issues to address. Lastly, we will emphasize areas that are still in need of exploration which would greatly improve our understanding of the group. 

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. 

Abstract The use of gDNAs isolated from museum specimens for high throughput sequencing, especially targeted sequencing in the context of phylogenetics, is a common practice. Yet, little understanding has been focused on comparing the quality of DNA and results of sequencing museum DNAs. Dragonflies and damselflies are ubiquitous in freshwater ecosystems and are commonly collected and preserved insects in museum collections hence their use in this study. However, the history of odonate preservation across time and museums has resulted in wide variability in the success of viable DNA extraction, necessitating an assessment of their usefulness in genetic studies. Using Anchored Hybrid Enrichment probes, we sequenced DNA from samples at 2 museums, 48 from the American Museum of Natural History (AMNH) in NYC, USA and 46 from the Naturalis Biodiversity Center (RMNH) in Leiden, Netherlands ranging from global collection localities and across a 120-year time span. We recovered at least 4 loci out of an >1,000 locus probe set for all samples, with the average capture being ~385 loci (539 loci on average when a clade of ambiguous taxa omitted). Neither specimen age nor size was a good predictor of locus capture, but recapture rates differed significantly between museums. Samples from the AMNH had lower overall locus capture than the RMNH, perhaps due to differences in specimen storage over time. 

Planetary extinction of biodiversity underscores the need for taxonomy. Here, we scrutinize spider taxonomy over the last decade (2008–2018), compiling 2083 published accounts of newly described species. We evaluated what type of data were used to delineate species, whether data were made freely available, whether an explicit species hypothesis was stated, what types of media were used, the sample sizes, and the degree to which species constructs were integrative. The findings we report reveal that taxonomy remains largely descriptive, not integrative, and provides no explicit conceptual framework. Less than 4% of accounts explicitly stated a species concept and over one-third of all new species described were based on 1–2 specimens or only one sex. Only ~5% of studies made data freely available, and only ~14% of all newly described species employed more than one line of evidence, with molecular data used in ~6% of the studies. These same trends have been discovered in other animal groups, and therefore we find it logical that taxonomists face an uphill challenge when justifying the scientific rigor of their field and securing the needed resources. To move taxonomy forward, we make recommendations that, if implemented, will enhance its rigor, repeatability, and scientific standards.