To and fro in the archipelago: Repeated inter-island dispersal and New Guinea's orogeny affect diversification of Delias, the world's largest butterfly genus

The world's largest butterfly genus Delias, commonly known as Jezebels, comprises ca. 251 species found throughout Asia, Australia, and Melanesia. Most species are endemic to islands in the Indo-Australian Archipelago or to New Guinea and nearby islands in Melanesia, and many species are restricted to montane habitats over 1200 m. We inferred an extensively sampled and well-supported molecular phylogeny of the group to better understand the spatial and temporal dimensions of its diversification. The remarkable diversity of Delias evolved in just ca. 15-16 Myr (crown age). The most recent common ancestor of a clade with most of the species dispersed out of New Guinea ca. 14 Mya, but at least six subsequently diverging lineages dispersed back to the island. Diversification was associated with frequent dispersal of lineages among the islands of the Indo-Australian Archipelago, and the divergence of sister taxa on a single landmass was rare and occurred only on the largest islands, most notably on New Guinea. We conclude that frequent inter-island dispersal during the Neogene-likely facilitated by frequent sea level change-sparked much diversification during that period. Many extant New Guinea lineages started diversifying 5 Mya, suggesting that orogeny facilitated their diversification. Our results largely agree with the most recently proposed species group classification system, and we use our large taxon sample to extend this system to all described species. Finally, we summarize recent insights to speculate how wing pattern evolution, mimicry, and sexual selection might also contribute to these butterflies' rapid speciation and diversification.

Comprehensive phylogeny of Pieridae butterflies reveals strong correlation between diversification and temperature

Temperature is thought to be a key factor influencing global species richness patterns. We investigate the link between temperature and diversification in the butterfly family Pieridae by combining next generation DNA sequences and published molecular data with fine-grained distribution data. We sampled nearly 600 pierid butterfly species to infer the most comprehensive molecular phylogeny of the family and curated a distribution dataset of more than 800,000 occurrences. We found strong evidence that species in environments with more stable daily temperatures or cooler maximum temperatures in the warm seasons have higher speciation rates. Furthermore, speciation and extinction rates decreased in tandem with global temperatures through geological time, resulting in a constant net diversification.

Long read genome assembly of Automeris io (Lepidoptera: Saturniidae) an emerging model for the evolution of deimatic displays

Automeris moths are a morphologically diverse group with 135 described species that have a geographic range that spans from the New World temperate zone to the Neotropics. Many Automeris have elaborate hindwing eyespots that are thought to deter or disrupt the attack of potential predators, allowing the moth time to escape. The Io moth (Automeris io), known for its striking eyespots, is a well-studied species within the genus and is an emerging model system to study the evolution of deimatism. Existing research on the eyespot pattern development will be augmented by genomic resources that allow experimental manipulation of this emerging model. Here, we present a high-quality, PacBio HiFi genome assembly for Io moth to aid existing research on the molecular development of eyespots and future research on other deimatic traits. This 490 Mb assembly is highly contiguous (N50 = 15.78 mbs) and complete (benchmarking universal single-copy orthologs = 98.4%). Additionally, we were able to recover orthologs of genes previously identified as being involved in wing pattern formation and movement.

Substantial urbanization-driven declines of larval and adult moths in a subtropical environment

Recent work has shown the decline of insect abundance, diversity and biomass, with potential implications for ecosystem services. These declines are especially pronounced in regions with high human activity, and urbanization is emerging as a significant contributing factor. However, the scale of these declines and the traits that determine variation in species-specific responses remain less well understood, especially in subtropical and tropical regions, where insect diversity is high and urban footprints are rapidly expanding. Here, we surveyed moths across an entire year in protected forested sites across an urbanization gradient to test how caterpillar and adult life stages of subtropical moths (Lepidoptera) are impacted by urbanization. Specifically, we assess how urban development affects the total biomass of caterpillars, abundance of adult moths and quantify how richness and phylogenetic diversity of macro-moths are impacted by urban development. Additionally, we explore how life-history traits condition species' responses to urban development. At the community level, we find that urban development decreases caterpillar biomass and adult moth abundance. We also find sharp declines of adult macro-moths in response to urban development across the phylogeny, leading to a decrease in species richness and phylogenetic diversity in more urban sites. Finally, our study found that smaller macro-moths are less impacted by urban development than larger macro-moths in subtropical environments, perhaps highlighting the tradeoffs of metabolic costs of urban heat favoring smaller moths over the relative benefits of dispersal for larger moths. In summary, our research underscores the far-reaching consequences of urbanization on moths and provides compelling evidence that urban forests alone may not be sufficient to safeguard biodiversity in cities.

Large-scale genomic data reveal the phylogeny and evolution of owlet moths (Noctuoidea)

The owlet moths (Noctuoidea; ~43-45K described species) are one of the most ecologically diverse and speciose superfamilies of animals. Moreover, they comprise some of the world's most notorious pests of agriculture and forestry. Despite their contributions to terrestrial biodiversity and impacts on ecosystems and economies, the evolutionary history of Noctuoidea remains unclear because the superfamily lacks a statistically robust phylogenetic and temporal framework. We reconstructed the phylogeny of Noctuoidea using data from 1234 genes (946.4 kb nucleotides) obtained from the genome and transcriptome sequences of 76 species. The relationships among the six families of Noctuoidea were well resolved and consistently recovered based on both concatenation and gene coalescence approaches, supporting the following relationships: Oenosandridae + (Notodontidae + (Erebidae + (Nolidae + (Euteliidae + Noctuidae)))). A Yule tree prior with three unlinked molecular clocks was identified as the preferred BEAST analysis using marginal-likelihood estimations. The crown age of Noctuoidea was estimated at 74.5 Ma, with most families originating before the end of the Paleogene (23 Ma). Our study provides the first statistically robust phylogenetic and temporal framework for Noctuoidea, including all families of owlet moths, based on large-scale genomic data.

Evolutionary genomics of three agricultural pest moths reveals rapid evolution of host adaptation and immune-related genes

BACKGROUND

Understanding the genotype of pest species provides an important baseline for designing integrated pest management (IPM) strategies. Recently developed long-read sequence technologies make it possible to compare genomic features of nonmodel pest species to disclose the evolutionary path underlying the pest species profiles. Here we sequenced and assembled genomes for 3 agricultural pest gelechiid moths: Phthorimaea absoluta (tomato leafminer), Keiferia lycopersicella (tomato pinworm), and Scrobipalpa atriplicella (goosefoot groundling moth). We also compared genomes of tomato leafminer and tomato pinworm with published genomes of Phthorimaea operculella and Pectinophora gossypiella to investigate the gene family evolution related to the pest species profiles.

RESULTS

We found that the 3 solanaceous feeding species, P. absoluta, K. lycopersicella, and P. operculella, are clustered together. Gene family evolution analyses with the 4 species show clear gene family expansions on host plant-associated genes for the 3 solanaceous feeding species. These genes are involved in host compound sensing (e.g., gustatory receptors), detoxification (e.g., ABC transporter C family, cytochrome P450, glucose-methanol-choline oxidoreductase, insect cuticle proteins, and UDP-glucuronosyl), and digestion (e.g., serine proteases and peptidase family S1). A gene ontology enrichment analysis of rapid evolving genes also suggests enriched functions in host sensing and immunity.

CONCLUSIONS

Our results of family evolution analyses indicate that host plant adaptation and pathogen defense could be important drivers in species diversification among gelechiid moths.

CRISPR-based diagnostics detects invasive insect pests

Rapid identification of organisms is essential for many biological and medical disciplines, from understanding basic ecosystem processes, disease diagnosis, to the detection of invasive pests. CRISPR-based diagnostics offers a novel and rapid alternative to other identification methods and can revolutionize our ability to detect organisms with high accuracy. Here we describe a CRISPR-based diagnostic developed with the universal cytochrome-oxidase 1 gene (CO1). The CO1 gene is the most sequenced gene among Animalia, and therefore our approach can be adopted to detect nearly any animal. We tested the approach on three difficult-to-identify moth species (Keiferia lycopersicella, Phthorimaea absoluta and Scrobipalpa atriplicella) that are major invasive pests globally. We designed an assay that combines recombinase polymerase amplification (RPA) with CRISPR for signal generation. Our approach has a much higher sensitivity than real-time PCR assays and achieved 100% accuracy for identification of all three species, with a detection limit of up to 120 fM for P. absoluta and 400 fM for the other two species. Our approach does not require a sophisticated laboratory, reduces the risk of cross-contamination, and can be completed in less than 1 h. This work serves as a proof of concept that has the potential to revolutionize animal detection and monitoring.

A framework for understanding post-detection deception in predator-prey interactions

Predators and prey exist in persistent conflict that often hinges on deception-the transmission of misleading or manipulative signals-as a means for survival. Deceptive traits are widespread across taxa and sensory systems, representing an evolutionarily successful and common strategy. Moreover, the highly conserved nature of the major sensory systems often extends these traits past single species predator-prey interactions toward a broader set of perceivers. As such, deceptive traits can provide a unique window into the capabilities, constraints and commonalities across divergent and phylogenetically-related perceivers. Researchers have studied deceptive traits for centuries, but a unified framework for categorizing different types of post-detection deception in predator-prey conflict still holds potential to inform future research. We suggest that deceptive traits can be distinguished by their effect on object formation processes. Perceptual objects are composed of physical attributes (what) and spatial (where) information. Deceptive traits that operate after object formation can therefore influence the perception and processing of either or both of these axes. We build upon previous work using a perceiver perspective approach to delineate deceptive traits by whether they closely match the sensory information of another object or create a discrepancy between perception and reality by exploiting the sensory shortcuts and perceptual biases of their perceiver. We then further divide this second category, sensory illusions, into traits that distort object characteristics along either the what or where axes, and those that create the perception of whole novel objects, integrating the what/where axes. Using predator-prey examples, we detail each step in this framework and propose future avenues for research. We suggest that this framework will help organize the many forms of deceptive traits and help generate predictions about selective forces that have driven animal form and behavior across evolutionary time.

A high-quality, long-read genome assembly of the whitelined sphinx moth (Lepidoptera: Sphingidae: Hyles lineata) shows highly conserved melanin synthesis pathway genes

The sphinx moth genus Hyles comprises 29 described species inhabiting all continents except Antarctica. The genus diverged relatively recently (40-25 MYA), arising in the Americas and rapidly establishing a cosmopolitan distribution. The whitelined sphinx moth, Hyles lineata, represents the oldest extant lineage of this group and is one of the most widespread and abundant sphinx moths in North America. Hyles lineata exhibits the large body size and adept flight control characteristic of the sphinx moth family (Sphingidae), but it is unique in displaying extreme larval color variation and broad host plant use. These traits, in combination with its broad distribution and high relative abundance within its range, have made H. lineata a model organism for studying phenotypic plasticity, plant-herbivore interactions, physiological ecology, and flight control. Despite being one of the most well-studied sphinx moths, little data exist on genetic variation or regulation of gene expression. Here, we report a high-quality genome showing high contiguity (N50 of 14.2 Mb) and completeness (98.2% of Lepidoptera BUSCO genes), an important first characterization to facilitate such studies. We also annotate the core melanin synthesis pathway genes and confirm that they have high sequence conservation with other moths and are most similar to those of another, well-characterized sphinx moth, the tobacco hornworm (Manduca sexta).

A global phylogeny of butterflies reveals their evolutionary history, ancestral hosts and biogeographic origins

Butterflies are a diverse and charismatic insect group that are thought to have evolved with plants and dispersed throughout the world in response to key geological events. However, these hypotheses have not been extensively tested because a comprehensive phylogenetic framework and datasets for butterfly larval hosts and global distributions are lacking. We sequenced 391 genes from nearly 2,300 butterfly species, sampled from 90 countries and 28 specimen collections, to reconstruct a new phylogenomic tree of butterflies representing 92% of all genera. Our phylogeny has strong support for nearly all nodes and demonstrates that at least 36 butterfly tribes require reclassification. Divergence time analyses imply an origin ~100 million years ago for butterflies and indicate that all but one family were present before the K/Pg extinction event. We aggregated larval host datasets and global distribution records and found that butterflies are likely to have first fed on Fabaceae and originated in what is now the Americas. Soon after the Cretaceous Thermal Maximum, butterflies crossed Beringia and diversified in the Palaeotropics. Our results also reveal that most butterfly species are specialists that feed on only one larval host plant family. However, generalist butterflies that consume two or more plant families usually feed on closely related plants.

CRISPR-based diagnostics detects invasive insect pests

Rapid identification of organisms is essential across many biological and medical disciplines, from understanding basic ecosystem processes and how organisms respond to environmental change, to disease diagnosis and detection of invasive pests. CRISPR-based diagnostics offers a novel and rapid alternative to other identification methods and can revolutionize our ability to detect organisms with high accuracy. Here we describe a CRISPR-based diagnostic developed with the universal cytochrome-oxidase 1 gene (CO1). The CO1 gene is the most sequenced gene among Animalia, and therefore our approach can be adopted to detect nearly any animal. We tested the approach on three difficult-to-identify moth species (Keiferia lycopersicella, Phthorimaea absoluta, and Scrobipalpa atriplicella) that are major invasive pests globally. We designed an assay that combines recombinase polymerase amplification (RPA) with CRISPR for signal generation. Our approach has a much higher sensitivity than other real time-PCR assays and achieved 100% accuracy for identification of all three species, with a detection limit of up to 120 fM for P. absoluta and 400 fM for the other two species. Our approach does not require a lab setting, reduces the risk of cross-contamination, and can be completed in less than one hour. This work serves as a proof of concept that has the potential to revolutionize animal detection and monitoring.

Allelic resolution of insect and spider silk genes reveals hidden genetic diversity

Arthropod silk is vital to the evolutionary success of hundreds of thousands of species. The primary proteins in silks are often encoded by long, repetitive gene sequences. Until recently, sequencing and assembling these complex gene sequences has proven intractable given their repetitive structure. Here, using high-quality long-read sequencing, we show that there is extensive variation-both in terms of length and repeat motif order-between alleles of silk genes within individual arthropods. Further, this variation exists across two deep, independent origins of silk which diverged more than 500 Mya: the insect clade containing caddisflies and butterflies and spiders. This remarkable convergence in previously overlooked patterns of allelic variation across multiple origins of silk suggests common mechanisms for the generation and maintenance of structural protein-coding genes. Future genomic efforts to connect genotypes to phenotypes should account for such allelic variation.

Evidence for a single, ancient origin of a genus-wide alternative life history strategy

Understanding the evolutionary origins and factors maintaining alternative life history strategies (ALHS) within species is a major goal of evolutionary research. While alternative alleles causing discrete ALHS are expected to purge or fix over time, one-third of the ~90 species of Colias butterflies are polymorphic for a female-limited ALHS called Alba. Whether Alba arose once, evolved in parallel, or has been exchanged among taxa is currently unknown. Using comparative genome-wide association study (GWAS) and population genomic analyses, we placed the genetic basis of Alba in time-calibrated phylogenomic framework, revealing that Alba evolved once near the base of the genus and has been subsequently maintained via introgression and balancing selection. CRISPR-Cas9 mutagenesis was then used to verify a putative cis-regulatory region of Alba, which we identified using phylogenetic foot printing. We hypothesize that this cis-regulatory region acts as a modular enhancer for the induction of the Alba ALHS, which has likely facilitated its long evolutionary persistence.

Measuring compound eye optics with microscope and microCT images

With a great variety of shapes and sizes, compound eye morphologies give insight into visual ecology, development, and evolution, and inspire novel engineering. In contrast to our own camera-type eyes, compound eyes reveal their resolution, sensitivity, and field of view externally, provided they have spherical curvature and orthogonal ommatidia. Non-spherical compound eyes with skewed ommatidia require measuring internal structures, such as with MicroCT (µCT). Thus far, there is no efficient tool to characterize compound eye optics, from either 2D or 3D data, automatically. Here we present two open-source programs: (1) the ommatidia detecting algorithm (ODA), which measures ommatidia count and diameter in 2D images, and (2) a µCT pipeline (ODA-3D), which calculates anatomical acuity, sensitivity, and field of view across the eye by applying the ODA to 3D data. We validate these algorithms on images, images of replicas, and µCT eye scans from ants, fruit flies, moths, and a bee.

The genome sequence of the Large Skipper, Ochlodes sylvanus, (Esper, 1777)

We present a genome assembly from an individual female Ochlodes sylvanus, the Large Skipper (Arthropoda; Insecta; Lepidoptera; Hesperiidae). The genome sequence is 380 megabases in span. Most of the assembly (99.97%) is scaffolded into 30 chromosomal pseudomolecules, including the assembled W and Z sex chromosomes. The mitochondrial genome has also been assembled and is 17.1 kilobases in length. Gene annotation of this assembly on Ensembl identified 13,451 protein coding genes.

Testing bird-driven diurnal trade-offs of the moon moth's anti-bat tail

Traits are often caught in a dynamic tension of countervailing evolutionary pressures. Trade-offs can be imposed by predators evolutionarily curtailing the conspicuousness of a sexually selected trait, or acting in opposition to another natural selection pressure, for instance, a different predator with a divergent hunting strategy. Some moon moths (Saturniidae) have long hindwing tails that thwart echolocating bat attacks at night, allowing the moth to escape. These long tails may come at a cost, however, if they make the moth's roosting form more conspicuous to visually foraging predators during the day. To test this potential trade-off, we offered wild-caught Carolina wrens (Thryothorus ludovicianus) pastry dough models with real Actias luna wings that were either intact or had tails experimentally removed. We video recorded wrens foraging on models and found that moth models with tails did not experience increased detection and attack by birds. Thus, this elaborate trait, while obvious to human observers, does not seem to come at a cost of increased avian predator attention. The evolution of long hindwing tails, likely driven by echolocating predators at night, does not seem to be limited by opposing diurnal constraints. This study demonstrates the importance of testing presumed trade-offs and provides hypotheses for future testing.

Mezcal worm in a bottle: DNA evidence suggests a single moth species

Mezcals are distilled Mexican alcoholic beverages consumed by many people across the globe. One of the most popular mezcals is tequila, but there are other forms of mezcal whose production has been part of Mexican culture since the 17th century. It was not until the 1940-50s when the mezcal worm, also known as the "tequila worm", was placed inside bottles of non-tequila mezcal before distribution. These bottled larvae increased public attention for mezcal, especially in Asia, Europe, and the United States. Despite these larvae gaining global interest, their identity has largely remained uncertain other than that they are larvae of one of three distantly related holometabolous insects. We sequenced the COI gene from larvae in different kinds of commercially available mezcals. All larval DNA that amplified was identified as the agave redworm moth, Comadia redtenbacheri. Those that did not amplify were also confirmed morphologically to be the larva of this species.

Predictors of sequence capture in a large-scale anchored phylogenomics project

Next-generation sequencing (NGS) technologies have revolutionized phylogenomics by decreasing the cost and time required to generate sequence data from multiple markers or whole genomes. Further, the fragmented DNA of biological specimens collected decades ago can be sequenced with NGS, reducing the need for collecting fresh specimens. Sequence capture, also known as anchored hybrid enrichment, is a method to produce reduced representation libraries for NGS sequencing. The technique uses single-stranded oligonucleotide probes that hybridize with pre-selected regions of the genome that are sequenced via NGS, culminating in a dataset of numerous orthologous loci from multiple taxa. Phylogenetic analyses using these sequences have the potential to resolve deep and shallow phylogenetic relationships. Identifying the factors that affect sequence capture success could save time, money, and valuable specimens that might be destructively sampled despite low likelihood of sequencing success. We investigated the impacts of specimen age, preservation method, and DNA concentration on sequence capture (number of captured sequences and sequence quality) while accounting for taxonomy and extracted tissue type in a large-scale butterfly phylogenomics project. This project used two probe sets to extract 391 loci or a subset of 13 loci from over 6,000 butterfly specimens. We found that sequence capture is a resilient method capable of amplifying loci in samples of varying age (0–111 years), preservation method (alcohol, papered, pinned), and DNA concentration (0.020 ng/μl - 316 ng/ul). Regression analyses demonstrate that sequence capture is positively correlated with DNA concentration. However, sequence capture and DNA concentration are negatively correlated with sample age and preservation method. Our findings suggest that sequence capture projects should prioritize the use of alcohol-preserved samples younger than 20 years old when available. In the absence of such specimens, dried samples of any age can yield sequence data, albeit with returns that diminish with increasing age.

The genome sequence of the peacock moth, Macaria notata (Linnaeus, 1758)

We present a genome assembly from an individual male Macaria notata (the peacock moth; Arthropoda; Insecta; Lepidoptera; Geometridae). The genome sequence is 394 megabases in span. The majority of the assembly (99.98%) is scaffolded into 29 chromosomal pseudomolecules with the Z sex chromosome assembled. The complete mitochondrial genome was also assembled and is 15.4 kilobases in length.

The genome sequence of the sallow kitten, Furcula furcula (Clerck, 1759)

We present a genome assembly from an individual male Furcula furcula (the sallow kitten; Arthropoda; Insecta; Lepidoptera; Notodontidae). The genome sequence is 736 megabases in span. The entire assembly (100%) is scaffolded into 29 chromosomal pseudomolecules, with the Z sex chromosome assembled. The complete mitochondrial genome was also assembled and is 17.2 kilobases in length.

The genome sequence of the 6-spot burnet, Zygaena filipendulae (Linnaeus, 1758)

We present a genome assembly from an individual female Zygaena filipendulae (6-spot burnet; Arthropoda; Insecta; Lepidoptera; Zygaenidae). The genome sequence is 365.9 megabases in span. The majority of the assembly (99.99%) is scaffolded into 31 chromosomal pseudomolecules, with the W and Z sex chromosomes assembled. The complete mitochondrial genome was also assembled and is 15.6 kilobases in length. Gene annotation of this assembly on Ensembl has identified 12,493 protein coding genes.

LepTraits 1.0 A globally comprehensive dataset of butterfly traits

Here, we present the largest, global dataset of Lepidopteran traits, focusing initially on butterflies (ca. 12,500 species records). These traits are derived from field guides, taxonomic treatments, and other literature resources. We present traits on wing size, phenology,voltinism, diapause/overwintering stage, hostplant associations, and habitat affinities (canopy, edge, moisture, and disturbance). This dataset will facilitate comparative research on butterfly ecology and evolution and our goal is to inspire future research collaboration and the continued development of this dataset.

Measurement(s)	Wingspan • Habitat Affinity • oviposition • voltinism • phenology • hostplant association
Technology Type(s)	natural language processing
Sample Characteristic - Organism	Lepidoptera
Sample Characteristic - Location	Global

Long-read HiFi sequencing correctly assembles repetitive heavy fibroin silk genes in new moth and caddisfly genomes

Insect silk is a versatile biomaterial. Lepidoptera and Trichoptera display some of the most diverse uses of silk, with varying strength, adhesive qualities, and elastic properties. Silk fibroin genes are long (>20 Kbp), with many repetitive motifs that make them challenging to sequence. Most research thus far has focused on conserved N- and C-terminal regions of fibroin genes because a full comparison of repetitive regions across taxa has not been possible. Using the PacBio Sequel II system and SMRT sequencing, we generated high fidelity (HiFi) long-read genomic and transcriptomic sequences for the Indianmeal moth (Plodia interpunctella) and genomic sequences for the caddisfly Eubasilissa regina. Both genomes were highly contiguous (N50  = 9.7 Mbp/32.4 Mbp, L50  = 13/11) and complete (BUSCO complete  = 99.3%/95.2%), with complete and contiguous recovery of silk heavy fibroin gene sequences. We show that HiFi long-read sequencing is helpful for understanding genes with long, repetitive regions.

A DNA Extraction Method for Insects From Sticky Traps: Targeting a Low Abundance Pest, Phthorimaea absoluta (Lepidoptera: Gelechiidae), in Mixed Species Communities

Invasive insects can cause catastrophic damage to ecosystems and cost billions of dollars each year due to management expenses and lost revenue. Rapid detection is an important step to prevent invasive insects from spreading, but improvements in detection capabilities are needed for bulk collections like those from sticky traps. Here we present a bulk DNA extraction method designed for the detection of Phthorimaea absoluta Meyrick (Lepidoptera: Gelechiidae), an invasive moth that can decimate tomato crops. We test the extraction method for insect specimens on sticky traps, subjected to different temperature and humidity conditions, and among mock insect communities left in the field for up to 21 d. We find that the extraction method yielded high success (>92%) in recovering target DNA across field and lab trials, without a decline in recovery after three weeks, across all treatments. These results may have a large impact on tomato growing regions where P. absoluta is in the early stages of invasion or not yet present. The extraction method can also be used to improve detection capabilities for other bulk insect collections, especially those using sticky traps, to the benefit of pest surveys and biodiversity studies.

Population differentiation and structural variation in the Manduca sexta genome across the United States

Many species that are extensively studied in the laboratory are less well characterized in their natural habitat, and laboratory strains represent only a small fraction of the variation in a species’ genome. Here we investigate genomic variation in 3 natural North American populations of an agricultural pest and a model insect for many scientific disciplines, the tobacco hornworm (Manduca sexta). We show that hornworms from Arizona, Kansas, and North Carolina are genetically distinct, with Arizona being particularly differentiated from the other 2 populations using Illumina whole-genome resequencing. Peaks of differentiation exist across the genome, but here, we focus in on the most striking regions. In particular, we identify 2 likely segregating inversions found in the Arizona population. One inversion on the Z chromosome may enhance adaptive evolution of the sex chromosome. The larger, 8 Mb inversion on chromosome 12 contains a pseudogene which may be involved in the exploitation of a novel hostplant in Arizona, but functional genetic assays will be required to support this hypothesis. Nevertheless, our results reveal undiscovered natural variation and provide useful genomic data for both pest management and evolutionary genetics of this insect species.

A diversification relay race from Caribbean-Mesoamerica to the Andes: historical biogeography of Xylophanes hawkmoths

The regions of the Andes and Caribbean-Mesoamerica are both hypothesized to be the cradle for many Neotropical lineages, but few studies have fully investigated the dynamics and interactions between Neotropical bioregions. The New World hawkmoth genus Xylophanes is the most taxonomically diverse genus in the Sphingidae, with the highest endemism and richness in the Andes and Caribbean-Mesoamerica. We integrated phylogenomic and DNA barcode data and generated the first time-calibrated tree for this genus, covering 93.8% of the species diversity. We used event-based likelihood ancestral area estimation and biogeographic stochastic mapping to examine the speciation and dispersal dynamics of Xylophanes across bioregions. We also used trait-dependent diversification models to compare speciation and extinction rates of lineages associated with different bioregions. Our results indicate that Xylophanes originated in Caribbean-Mesoamerica in the Late Miocene, and immediately diverged into five major clades. The current species diversity and distribution of Xylophanes can be explained by two consecutive phases. In the first phase, the highest Xylophanes speciation and emigration rates occurred in the Caribbean-Mesoamerica, and the highest immigration rates occurred in the Andes, whereas in the second phase the highest immigration rates were found in Amazonia, and the Andes had the highest speciation and emigration rates.

Molecular phylogeny, systematics and generic classification of the butterfly subfamily Trapezitinae (Lepidoptera: Papilionoidea: Hesperiidae)

Trapezitinae skippers are restricted to Australia and New Guinea. Despite decades of taxonomic work, their systematics and phylogeny remain little understood. To resolve the composition of genera and determine their evolutionary relationships, we inferred a comprehensive multilocus molecular phylogeny of Trapezitinae. Our results recover a monophyletic Trapezitinae as sister to Barcinae, with a poorly resolved backbone possibly indicating an early rapid radiation. We recover two main clades comprising all currently described genera, including the previously contentious Prada Evans, 1949 but excluding Tiacellia Evans, 1949. Several genera are recovered as paraphyletic or polyphyletic, rendering the classification of Trapezitinae incompatible with the new phylogeny. Therefore, we synonymize Motasingha Watson, 1893 syn. nov. and Oreisplanus Waterhouse & Lyell, 1914 syn. nov. with Hesperilla Hewitson, 1868 and Neohesperilla Waterhouse & Lyell, 1914 syn. nov. with Toxidia Mabille, 1891. To reflect the placement of Anisynta dominula outside of Anisynta, we describe the new genus Atkinsia Braby & Toussaint gen. nov., which includes the sole species Atkinsia dominula (Plötz, 1884) comb. nov. Two species of Toxidia and two species of Signeta Waterhouse & Lyell, 1914 are placed into Timoconia Strand, 1909, yielding four new combinations: Timoconia melania (Waterhouse, 1903) comb. nov., Timoconia peron (Latreille, 1824) comb. nov., Timoconia flammeata (Butler, 1882) comb. nov. and Timoconia tymbophora (Meyrick & Lower, 1902) comb. nov. Thus, Signeta Waterhouse & Lyell, 1914 syn. nov. is now regarded as a junior synonym of Timoconia. Overall, our phylogeny has provided the basis for 20 nomenclatural changes at the species and subspecies level, including 14 new combinations.

The evolution of two distinct strategies of moth flight

Across insects, wing shape and size have undergone dramatic divergence even in closely related sister groups. However, we do not know how morphology changes in tandem with kinematics to support body weight within available power and how the specific force production patterns are linked to differences in behaviour. Hawkmoths and wild silkmoths are diverse sister families with divergent wing morphology. Using three-dimensional kinematics and quasi-steady aerodynamic modelling, we compare the aerodynamics and the contributions of wing shape, size and kinematics in 10 moth species. We find that wing movement also diverges between the clades and underlies two distinct strategies for flight. Hawkmoths use wing kinematics, especially high frequencies, to enhance force and wing morphologies that reduce power. Silkmoths use wing morphology to enhance force, and slow, high-amplitude wingstrokes to reduce power. Both strategies converge on similar aerodynamic power and can support similar body weight ranges. However, inter-clade within-wingstroke force profiles are quite different and linked to the hovering flight of hawkmoths and the bobbing flight of silkmoths. These two moth groups fly more like other, distantly related insects than they do each other, demonstrating the diversity of flapping flight evolution and a rich bioinspired design space for robotic flappers.

Hidden phylogenomic signal helps elucidate arsenurine silkmoth phylogeny and the evolution of body size and wing shape trade-offs

One of the key objectives in biological research is understanding how evolutionary processes have produced Earth's diversity. A critical step towards revealing these processes is an investigation of evolutionary tradeoffs - that is, the opposing pressures of multiple selective forces. For millennia, nocturnal moths have had to balance successful flight, as they search for mates or host plants, with evading bat predators. However, the potential for evolutionary trade-offs between wing shape and body size are poorly understood. In this study, we used phylogenomics and geometric morphometrics to examine the evolution of wing shape in the wild silkmoth subfamily Arsenurinae (Saturniidae) and evaluate potential evolutionary relationships between body size and wing shape. The phylogeny was inferred based on 782 loci from target capture data of 42 arsenurine species representing all 10 recognized genera. After detecting in our data one of the most vexing problems in phylogenetic inference - a region of a tree that possesses short branches and no "support" for relationships (i.e., a polytomy), we looked for hidden phylogenomic signal (i.e., inspecting differing phylogenetic inferences, alternative support values, quartets, and phylogenetic networks) to better illuminate the most probable generic relationships within the subfamily. We found there are putative evolutionary trade-offs between wing shape, body size, and the interaction of fore- and hindwing shape. Namely, body size tends to decrease with increasing hindwing length but increases as forewing shape becomes more complex. Additionally, the type of hindwing (i.e., tail or no tail) a lineage possesses has a significant effect on the complexity of forewing shape. We outline possible selective forces driving the complex hindwing shapes that make Arsenurinae, and silkmoths as a whole, so charismatic.

Phylogeny of gracillariid leaf-mining moths: evolution of larval behaviour inferred from phylogenomic and Sanger data

Gracillariidae is the most taxonomically diverse cosmopolitan leaf-mining moth family, consisting of nearly 2000 named species in 105 described genera, classified into eight extant subfamilies. The majority of gracillariid species are internal plant feeders as larvae, creating mines and galls in plant tissue. Despite their diversity and ecological adaptations, their phylogenetic relationships, especially among subfamilies, remain uncertain. Genomic data (83 taxa, 589 loci) were integrated with Sanger data (130 taxa, 22 loci), to reconstruct a phylogeny of Gracillariidae. Based on analyses of both datasets combined and analyzed separately, monophyly of Gracillariidae and all its subfamilies, monophyly of the clade "LAMPO" (subfamilies: Lithocolletinae, Acrocercopinae, Marmarinae, Phyllocnistinae, and Oecophyllembiinae) and relationships of its subclade "AMO" (subfamilies: Acrocercopinae, Marmarinae, and Oecophyllembiinae) were strongly supported. A sister-group relationship of Ornixolinae to the remainder of the family, and a monophyletic leaf roller lineage (Callicercops Vári + Parornichinae) + Gracillariinae, as sister to the "LAMPO" clade were supported by the most likely tree. Dating analyses indicate a mid-Cretaceous (105.3 Ma) origin of the family, followed by a rapid diversification into the nine subfamilies predating the Cretaceous-Palaeogene extinction. We hypothesize that advanced larval behaviours, such as making keeled or tentiform blotch mines, rolling leaves and galling, allowed gracillariids to better avoid larval parasitoids allowing them to further diversify. Finally, we stabilize the classification by formally re-establishing the subfamily ranks of Marmarinae stat.rev., Oecophyllembiinae stat.rev. and Parornichinae stat.rev., and erect a new subfamily, Callicercopinae Li, Ohshima and Kawahara to accommodate the enigmatic genus Callicercops.

Food Plant Shifts Drive the Diversification of Sack-Bearer Moths

AbstractLepidoptera are a highly diverse group of herbivorous insects; however, some superfamilies have relatively few species. Two alternative hypotheses for drivers of Lepidoptera diversity are shifts in food plant use or shifts from concealed to external feeding as larvae. Many studies address the former hypothesis but with bias toward externally feeding taxa. One of the most striking examples of species disparity between sister lineages in Lepidoptera is between the concealed-feeding sack-bearer moths (Mimallonoidea), which contain about 300 species, and externally feeding Macroheterocera, which have over 74,000 species. We provide the first dated tree of Mimallonidae to understand the diversification dynamics of these moths in order to fill a knowledge gap pertaining to drivers of diversity within an important concealed-feeding clade. We find that Mimallonidae is an ancient Lepidoptera lineage that originated in the Cretaceous ∼105 million years ago and has had a close association with the plant order Myrtales for the past 40 million years. Diversification dynamics are tightly linked with food plant usage in this group. Reliance on Myrtales may have influenced diversification of Mimallonidae because clades that shifted away from the ancestral condition of feeding on Myrtales have the highest speciation rates in the family.

First Annotated Genome of a Mandibulate Moth, Neomicropteryx cornuta, Generated Using PacBio HiFi Sequencing

We provide a new, annotated genome assembly of Neomicropteryx cornuta, a species of the so-called mandibulate archaic moths (Lepidoptera: Micropterigidae). These moths belong to a lineage that is thought to have split from all other Lepidoptera more than 300 Ma and are consequently vital to understanding the early evolution of superorder Amphiesmenoptera, which contains the order Lepidoptera (butterflies and moths) and its sister order Trichoptera (caddisflies). Using PacBio HiFi sequencing reads, we assembled a highly contiguous genome with a contig N50 of nearly 17 Mb. The assembled genome length of 541,115,538 bp is about half the length of the largest published Amphiesmenoptera genome (Limnephilus lunatus, Trichoptera) and double the length of the smallest (Papilio polytes, Lepidoptera). We find high recovery of universal single copy orthologs with 98.1% of BUSCO genes present and provide a genome annotation of 15,643 genes aided by resolved isoforms from PacBio IsoSeq data. This high-quality genome assembly provides an important resource for studying ecological and evolutionary transitions in the early evolution of Amphiesmenoptera.

Climate change effects on animal ecology: butterflies and moths as a case study

Butterflies and moths (Lepidoptera) are one of the most studied, diverse, and widespread animal groups, making them an ideal model for climate change research. They are a particularly informative model for studying the effects of climate change on species ecology because they are ectotherms that thermoregulate with a suite of physiological, behavioural, and phenotypic traits. While some species have been negatively impacted by climatic disturbances, others have prospered, largely in accordance with their diversity in life-history traits. Here we take advantage of a large repertoire of studies on butterflies and moths to provide a review of the many ways in which climate change is impacting insects, animals, and ecosystems. By studying these climate-based impacts on ecological processes of Lepidoptera, we propose appropriate strategies for species conservation and habitat management broadly across animals.

Adaptive shifts underlie the divergence in wing morphology in bombycoid moths

The evolution of flapping flight is linked to the prolific success of insects. Across Insecta, wing morphology diversified, strongly impacting aerodynamic performance. In the presence of ecological opportunity, discrete adaptive shifts and early bursts are two processes hypothesized to give rise to exceptional morphological diversification. Here, we use the sister-families Sphingidae and Saturniidae to answer how the evolution of aerodynamically important traits is linked to clade divergence and through what process(es) these traits evolve. Many agile Sphingidae evolved hover feeding behaviours, while adult Saturniidae lack functional mouth parts and rely on a fixed energy budget as adults. We find that Sphingidae underwent an adaptive shift in wing morphology coincident with life history and behaviour divergence, evolving small high aspect ratio wings advantageous for power reduction that can be moved at high frequencies, beneficial for flight control. By contrast, Saturniidae, which do not feed as adults, evolved large wings and morphology which surprisingly does not reduce aerodynamic power, but could contribute to their erratic flight behaviour, aiding in predator avoidance. We suggest that after the evolution of flapping flight, diversification of wing morphology can be potentiated by adaptative shifts, shaping the diversity of wing morphology across insects.

De novo genome assemblies of butterflies

BACKGROUND

The availability of thousands of genomes has enabled new advancements in biology. However, many genomes have not been investigated for their quality. Here we examine quality trends in a taxonomically diverse and well-known group, butterflies (Papilionoidea), and provide draft, de novo assemblies for all available butterfly genomes. Owing to massive genome sequencing investment and taxonomic curation, this is an excellent group to explore genome quality.

FINDINGS

We provide de novo assemblies for all 822 available butterfly genomes and interpret their quality in terms of completeness and continuity. We identify the 50 highest quality genomes across butterflies and conclude that the ringlet, Aphantopus hyperantus, has the highest quality genome. Our post-processing of draft genome assemblies identified 118 butterfly genomes that should not be reused owing to contamination or extremely low quality. However, many draft genomes are of high utility, especially because permissibility of low-quality genomes is dependent on the objective of the study. Our assemblies will serve as a key resource for papilionid genomics, especially for researchers without computational resources.

CONCLUSIONS

Quality metrics and assemblies are typically presented with annotated genome accessions but rarely with de novo genomes. We recommend that studies presenting genome sequences provide the assembly and some metrics of quality because quality will significantly affect downstream results. Transparency in quality metrics is needed to improve the field of genome science and encourage data reuse.

Evolutionary trade-offs between male secondary sexual traits revealed by a phylogeny of the hyperdiverse tribe Eumaeini (Lepidoptera: Lycaenidae)

Male butterflies in the hyperdiverse tribe Eumaeini possess an unusually complex and diverse repertoire of secondary sexual characteristics involved in pheromone production and dissemination. Maintaining multiple sexually selected traits is likely to be metabolically costly, potentially resulting in trade-offs in the evolution of male signals. However, a phylogenetic framework to test hypotheses regarding the evolution and maintenance of male sexual traits in Eumaeini has been lacking. Here, we infer a comprehensive, time-calibrated phylogeny from 379 loci for 187 species representing 91% of the 87 described genera. Eumaeini is a monophyletic group that originated in the late Oligocene and underwent rapid radiation in the Neotropics. We examined specimens of 818 of the 1096 described species (75%) and found that secondary sexual traits are present in males of 91% of the surveyed species. Scent pads and scent patches on the wings and brush organs associated with the genitalia were probably present in the common ancestor of Eumaeini and are widespread throughout the tribe. Brush organs and scent pads are negatively correlated across the phylogeny, exhibiting a trade-off in which lineages with brush organs are unlikely to regain scent pads and vice versa. In contrast, scent patches seem to facilitate the evolution of scent pads, although they are readily lost once scent pads have evolved. Our results illustrate the complex interplay between natural and sexual selection in the origin and maintenance of multiple male secondary sexual characteristics and highlight the potential role of sexual selection spurring diversification in this lineage.

Spatial phylogenetics of butterflies in relation to environmental drivers and angiosperm diversity across North America

Broad-scale, quantitative assessments of insect biodiversity and the factors shaping it remain particularly poorly explored. Here we undertook a spatial phylogenetic analysis of North American butterflies to test whether climate stability and temperature gradients have shaped their diversity and endemism. We also performed the first quantitative comparisons of spatial phylogenetic patterns between butterflies and flowering plants. We expected concordance between the two groups based on shared historical environmental drivers and presumed strong butterfly-host plant specializations. We instead found that biodiversity patterns in butterflies are strikingly different from flowering plants, especially warm deserts. In particular, butterflies show different patterns of phylogenetic clustering compared with flowering plants, suggesting differences in habitat conservation between the two groups. These results suggest that shared biogeographic histories and trophic associations do not necessarily assure similar diversity outcomes. The work has applied value in conservation planning, documenting warm deserts as a North American butterfly biodiversity hotspot.

Revision of the Hawaiian endemic leaf-mining moth genus Philodoria Walsingham (Lepidoptera: Gracillariidae): its conservation status, host plants and descriptions of thirteen new species

Philodoria Walsingham, 1907 is a threatened, Hawaiian endemic genus of leaf-mining gracillariid moths that feeds as larvae on many threatened and endangered Hawaiian endemic plants. These moths are poorly studied and species lack detailed descriptions of morphology, distribution data, and natural history information of adults and immatures. Based on extensive fieldwork from 2013 to 2016, and examination of museum specimens, we describe or redescribe 51 species, 13 which are new species and provide biological and distribution data for 41 species. The 13 new species and their host plants are: P. alakaiensis Kobayashi, Johns Kawahara, sp. n. (Asteraceae: Dubautia sp.), P. funkae Kobayashi, Johns Kawahara, sp. n. (Asteraceae: Wilkesia gymnoxiphium), P. haelaauensis Kobayashi, Johns Kawahara, sp. n. (Urticaceae: Pipturus albidus, P. rockii, Pipturus sp.), P. hesperomanniella Kobayashi, Johns Kawahara, sp. n. (Asteraceae: Hesperomannia arborescens and H. swezeyi), P. keaensis Kobayashi, Johns Kawahara, sp. n. (host unknown), P. keahii Kobayashi, Johns Kawahara, sp. n. (Asteraceae: Remya mauiensis), P. knudseniiella Kobayashi, Johns Kawahara, sp. n. (Asteraceae: Dubautia knudsenii subsp. nagate and D. latifolia), P. lama Kobayashi, Johns Kawahara, sp. n. (Ebanaceae: Diospyros sandwicensis and/or D. hillebrandii), P. limahuliensis Kobayashi, Johns Kawahara, sp. n. (Malvaceae: Hibiscus waimeae subsp. hannerae), P. napaliensis Kobayashi, Johns Kawahara, sp. n. (Ebanaceae: Diospyros sandwicensis and/or D. hillebrandii), P. obamaorum Kobayashi, Johns Kawahara, sp. n. (Urticaceae: Pipturus albidus, Pipturus sp.), P. opuhe Kobayashi, Johns Kawahara, sp. n. (Urticaceae: Urera kaalae and U. sandvicensis) and P. platyphylliella Kobayashi, Johns Kawahara, sp. n. (Asteraceae: Dubautia platyphylla). Types of 30 species were examined, lectotypes of 16 species are designated, and a key to all Philodoria species and all Hawaiian leaf-mining moths are provided. We also present a new Hawaiian name for Philodoria, which we call Hunelele 'elilau, meaning "tiny flier, leaf excavator", referring to their life history and behavior. Philodoria feeds on five herbraceous and woody host plant families, and 41 species persist in localized populations in Hawaii as of 2016. Twelve species (P. alakaiensis, P. funkae, P. haelaauensis, P. hespermanniella, P. kauaulaensis, P. keaensis, P. keahii, P. knudsniiella, P. limahuliensis, P. platyphylliella, P. sciallactis, P. wilkesiella) appear to be severely threatened, as these species are rare or feed exclusively on plants that are endangered or rare. We were unable to document 10 species (P. costalis, P. lipochaetaella, P. micropetala, P. nigrella, P. nigrelloides, P. opuhe, P. pipturiana, P. pipturicola, P. pittosporella, P. spilota) after many efforts to sample in or near their historical habitats. We believe these species may be extinct. Given their restricted distribution and the fact that many species feed on rare and endangered plants, there is a risk that many more Philodoria species may go extinct unless immediate conservation measures are taken.

Light environment drives evolution of color vision genes in butterflies and moths

Opsins, combined with a chromophore, are the primary light-sensing molecules in animals and are crucial for color vision. Throughout animal evolution, duplications and losses of opsin proteins are common, but it is unclear what is driving these gains and losses. Light availability is implicated, and dim environments are often associated with low opsin diversity and loss. Correlations between high opsin diversity and bright environments, however, are tenuous. To test if increased light availability is associated with opsin diversification, we examined diel niche and identified opsins using transcriptomes and genomes of 175 butterflies and moths (Lepidoptera). We found 14 independent opsin duplications associated with bright environments. Estimating their rates of evolution revealed that opsins from diurnal taxa evolve faster-at least 13 amino acids were identified with higher dN/dS rates, with a subset close enough to the chromophore to tune the opsin. These results demonstrate that high light availability increases opsin diversity and evolution rate in Lepidoptera.

Decline of Amateur Lepidoptera Collectors Threatens the Future of Specimen-Based Research

Amateur butterfly and moth collectors in the United States have procured more Lepidoptera specimens than professional scientists. The advent of large government-supported database efforts has made a quantitative examination of the impact of amateur collecting of these insects possible. We reviewed trends in Lepidoptera collecting since 1800, using more than 1 million United States lepidopteran specimens that have been collected into public databases. Our findings show a steep rise in the collection of specimens after World War II, followed by a short plateau and sharp decline in the late 1990s. In contrast, the rate of observations submitted to database groups dramatically increased around 2005. Declining acquisition of Lepidoptera specimens may compromise critically important testing of contemporary and future ecological, conservation, and evolutionary hypotheses on a grand scale, particularly given documented declines in insect populations. We suggest that increasing collaboration between professional and community-based scientists could alleviate the decline in amateur-collected specimens.

Is Sexual Conflict a Driver of Speciation? A Case Study With a Tribe of Brush-footed Butterflies

Understanding the evolutionary mechanisms governing the uneven distribution of species richness across the tree of life is a great challenge in biology. Scientists have long argued that sexual conflict is a key driver of speciation. This hypothesis, however, has been highly debated in light of empirical evidence. Recent advances in the study of macroevolution make it possible to test this hypothesis with more data and increased accuracy. In the present study, we use phylogenomics combined with four different diversification rate analytical approaches to test whether sexual conflict is a driver of speciation in brush-footed butterflies of the tribe Acraeini. The presence of a sphragis, an external mating plug found in most species among Acraeini, was used as a proxy for sexual conflict. Diversification analyses statistically rejected the hypothesis that sexual conflict is associated with shifts in diversification rates in Acraeini. This result contrasts with earlier studies and suggests that the underlying mechanisms driving diversification are more complex than previously considered. In the case of butterflies, natural history traits acting in concert with abiotic factors possibly play a stronger role in triggering speciation than does sexual conflict. [Acraeini butterflies; arms race; exon capture phylogenomics; Lepidoptera macroevolution; sexual selection; sphragis.].

Comparative Phylogenetics of Papilio Butterfly Wing Shape and Size Demonstrates Independent Hindwing and Forewing Evolution

The complex forces that shape butterfly wings have long been a subject of experimental and comparative research. Butterflies use their wings for flight, camouflage, mate recognition, warning, and mimicry. However, general patterns and correlations among wing shape and size evolution are still poorly understood. We collected geometric morphometric measurements from over 1400 digitized museum specimens of Papilio swallowtails and combined them with phylogenetic data to test two hypotheses: 1) forewing shape and size evolve independently of hindwing shape and size and 2) wing size evolves more quickly than wing shape. We also determined the major axes of wing shape variation and discovered that most shape variability occurs in hindwing tails and adjacent areas. We conclude that forewing shape and size are functionally and biomechanically constrained, whereas hindwings are more labile, perhaps in response to disruptive selective pressure for Batesian mimicry or against predation. The development of a significant, re-usable, digitized data resource will enable further investigation on tradeoffs between flight performance and ecological selective pressures, along with the degree to which intraspecific, local-scale selection may explain macroevolutionary patterns. [Batesian mimicry; Lepidoptera; geometric morphometrics; museum specimens.].

Review of recent taxonomic changes to the emerald moths (Lepidoptera: Geometridae: Geometrinae)

Background

The subfamily Geometrinae (Lepidoptera: Geometridae), commonly known as emerald moths, is an ecologically diverse group of moths with over 2,500 described species. Many taxonomic and phylogenetic studies of Geometrinae have been undertaken in the past decade, resulting in hundreds of new taxonomic changes since online publication of the most recent checklist in December 2007.

New information

This review synthesises the last 12 years of alpha-taxonomic research in Geometrinae. A comprehensive list of Geometrinae genus- and species-group descriptions, synonymies, combinations and other taxonomic changes, made since 2007, is provided. Since 2007, the known species richness of Geometrinae has increased from 2,529 to 2,642 species; an updated list of all these species is presented in a supplementary spreadsheet.

Cicinnus chambersi: a new species of sack-bearer moth (Lepidoptera, Mimallonidae, Cicinninae) from southeastern Arizona, USA

A new species of cicinnine Mimallonidae, Cicinnus chambersisp. nov., is described from the Sky Islands Region of southern Arizona, USA. The new species is closely related to C. mexicana (Druce), type locality Veracruz, Mexico, based on morphology and genetics. The other Cicinnus species known from the United States, the common C. melsheimeri (type locality Pennsylvania, USA) is morphologically and genetically distinct from both C. chambersi and C. mexicana. The new species is compared to C. mexicana and C. melsheimeri, as well as other Mexican Cicinnus. The life history of C. chambersi is unknown, but its description should facilitate future studies on this rarely reported North American mimallonid, a species which may have only recently become established in the United States. Cicinnus chambersi is the fifth known Mimallonidae species from the United States, and the first described from the country in nearly half a century.

Predator-induced stress responses in insects: A review

Predators can induce extreme stress and profound physiological responses in prey. Insects are the most dominant animal group on Earth and serve as prey for many different predators. Although insects have an extraordinary diversity of anti-predator behavioral and physiological responses, predator-induced stress has not been studied extensively in insects, especially at the molecular level. Here, we review the existing literature on physiological predator-induced stress responses in insects and compare what is known about insect stress to vertebrate stress systems. We conclude that many unrelated insects share a baseline pathway of predator-induced stress responses that we refer to as the octopamine-adipokinetic hormone (OAH) axis. We also present best practices for studying predator-induced stress responses in prey insects. We encourage investigators to compare neurophysiological responses to predator-related stress at the organismal, neurohormonal, tissue, and cellular levels within and across taxonomic groups. Studying stress-response variation between ecological contexts and across taxonomic levels will enable the field to build a holistic understanding of, and distinction between, taxon- and stimulus-specific responses relative to universal stress responses.

Transcriptomics illuminate the phylogenetic backbone of tiger beetles

Phylogenomics is progressing rapidly, allowing large strides forward into our understanding of the tree of life. In this study, we generated transcriptomes from ethanol-preserved specimens of 13 tiger beetle species (Coleoptera: Cicindelinae) and one Scaritinae outgroup. From these 14 transcriptomes and seven publicly available transcriptomes, we recovered an average of 2538 loci for phylogenetic analysis. We constructed an evolutionary tree of tiger beetles to examine deep-level relationships and examined the extent to which the composition of the dataset, missing data, gene tree inconsistency and codon position saturation impacted phylogenetic accuracy. Ethanol-preserved specimens yielded similar numbers of loci to specimens originally preserved in costly reagents, showcasing more flexibility in transcriptomics than anticipated. The number of loci and gene tree inconsistency had less impact on downstream results than third codon position saturation and missing data. Our results recovered tiger beetles as sister to Carabidae with strong support, confirming their taxonomic status as an independent family within Adephaga. Within tiger beetles, phylogenetic relationships were robust across all nodes. This new phylogenomic backbone represents a useful framework for future endeavours in tiger beetle systematics and serves as a starting point for the development of less costly target capture toolkits to expand the taxonomic breadth of the future tiger beetle tree of life.

Phylogeography and population genetics of pine butterflies: Sky islands increase genetic divergence

The sky islands of southeastern Arizona (AZ) mark a major transition zone between tropical and temperate biota and are considered a neglected biodiversity hotspot. Dispersal ability and host plant specificity are thought to impact the history and diversity of insect populations across the sky islands. We aimed to investigate the population structure and phylogeography of two pine-feeding pierid butterflies, the pine white (Neophasia menapia) and the Mexican pine white (Neophasia terlooii), restricted to these "islands" at this transition zone. Given their dependence on pines as the larval hosts, we hypothesized that habitat connectivity affects population structure and is at least in part responsible for their allopatry. We sampled DNA from freshly collected butterflies from 17 sites in the sky islands and adjacent high-elevation habitats and sequenced these samples using ddRADSeq. Up to 15,399 SNPs were discovered and analyzed in population genetic and phylogenetic contexts with Stacks and pyRAD pipelines. Low genetic differentiation in N. menapia suggests that it is panmictic. Conversely, there is strong evidence for population structure within N. terlooii. Each sky island likely contains a population of N. terlooii, and clustering is hierarchical, with populations on proximal mountains being more related to each other. The N. menapia habitat, which is largely contiguous, facilitates panmixia, while the N. terlooii habitat, restricted to the higher elevations on each sky island, creates distinct population structure. Phylogenetic results corroborate those from population genetic analyses. The historical climate-driven fluxes in forest habitat connectivity have implications for understanding the biodiversity of fragmented habitats.