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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. 

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. 

Darwin Core, the data standard used for sharing modern biodiversity and paleodiversity occurrence records, has previously lacked proper mechanisms for reporting what is known about the estimated age range of specimens from deep time. This has led to data providers putting these data in fields where they cannot easily be found by users, which impedes the reuse and improvement of these data by other researchers. Here we describe the development of the Chronometric Age Extension to Darwin Core, a ratified, community-developed extension that enables the reporting of ages of specimens from deeper time and the evidence supporting these estimates. The extension standardizes reporting about the methods or assays used to determine an age and other critical information like uncertainty. It gives data providers flexibility about the level of detail reported, focusing on the minimum information needed for reuse while still allowing for significant detail if providers have it. Providing a standardized format for reporting these data will make them easier to find and search and enable researchers to pinpoint specimens of interest for data improvement or accumulate more data for broad temporal studies. The Chronometric Age Extension was also the first community-managed vocabulary to undergo the new Biodiversity Informatics Standards (TDWG) review and ratification process, thus providing a blueprint for future Darwin Core extension development. 

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. 

Benchmark studies of insect populations are increasingly relevant and needed amid accelerating concern about insect trends in the Anthropocene. The growing recognition that insect populations may be in decline has given rise to a renewed call for insect population monitoring by scientists, and a desire from the broader public to participate in insect surveys. However, due to the immense diversity of insects and a vast assortment of data collection methods, there is a general lack of standardization in insect monitoring methods, such that a sudden and unplanned expansion of data collection may fail to meet its ecological potential or conservation needs without a coordinated focus on standards and best practices. To begin to address this problem, we provide simple guidelines for maximizing return on proven inventory methods that will provide insect benchmarking data suitable for a variety of ecological responses, including occurrence and distribution, phenology, abundance and biomass, and diversity and species composition. To track these responses, we present seven primary insect sampling methods—malaise trapping, light trapping, pan trapping, pitfall trappings, beating sheets, acoustic monitoring, and active visual surveys—and recommend standards while highlighting examples of model programs. For each method, we discuss key topics such as recommended spatial and temporal scales of sampling, important metadata to track, and degree of replication needed to produce rigorous estimates of ecological responses. We additionally suggest protocols for scalable insect monitoring, from backyards to national parks. Overall, we aim to compile a resource that can be used by diverse individuals and organizations seeking to initiate or improve insect monitoring programs in this era of rapid change.