Rich materials can provide more opportunities for exploring the mechanisms of speciation driven by sexual selection. Being the fastest‐evolving arthropods to date, the sword‐tailed crickets of Nudilla Gorochov, 1988 (= Laupala Otte, 1994) have rapidly diverged primarily due to the variability of their calling songs (sexual signals). In addition, they also exhibit morphological conservatism, with little variation between species. Similar circumstances can be seen in tree crickets (Oecanthinae), which have conservative morphology and a diverse range of song variations. Thus, we believe that tree crickets could serve as a model for research on sexual selection since they share a similar evolutionary history and mode of differentiation with Nudilla. However, due to the improper methods in analyzing the calling songs and nearly identical morphological features between taxa, there are many problems with the taxonomy of Oecanthinae in China. To solve these problems, we conducted an integrative taxonomic study of Chinese Oecanthinae based on comparative morphology, species delimitation, acoustical analysis, and phylogenetic analysis. This study recognized 12 Oecanthinae species in China, including four new species, and confirmed one new synonym and two misidentifications. Meanwhile, we confirmed the morphological stability of Oecanthinae, and revealed that variation in color, size, and morphology may be intraspecific polymorphism, which sometimes does not reflect the species relationships. The result indicates that the acoustic parameter freq.median can be used for efficient and accurate species delimitation in Oecanthinae. We speculate that incomplete species divergence leads to complexity in species relationships at the genetic level of Oecanthinae. The conservation of morphological characters, the interspecificity of songs and the complexity of species relationships suggest that sexual selection have played a role in the evolution of Oecanthinae. Our study resolves some systematic and taxonomic problems of Oecanthinae, clarifies the species relationships of Oecanthinae in China, and provides clues for expanding the cricket groups to be used in speciation studies.

Five new spider fossils of the family Macrothelidae (Araneae: Mygalomorphae) are described from mid‐ Cretaceous Kachin amber, Myanmar. A new genus Acanthomacrothele gen. nov. is established for three new species: Acanthomacrothele pauciverrucae sp. nov., Acanthomacrothele geminata sp. nov., and Acanthomacrothele longicaudata sp. nov. Both male and female specimens of A. pauciverrucae sp. nov. are described, representing a rare case of a fossil spider with both sexes known. We also describe an unidentified juvenile of Macrothelidae to document different developmental stages of Cretaceous species. To test the phylogenetic position of the new fossils, we undertook phylogenetic analyses using both topology‐unconstrained and topology‐constrained methods. Our analyses supported the placement of Acanthomacrothele gen. nov. in Macrothelidae, although its phylogenetic relationship to other genera of Macrothelidae differed among different analytical methods. The fossils documented here have elongated, widely spaced posterior lateral spinnerets, compact rectangular group of eyes on a tubercle, and more spines on male tibia of anterior legs than female, similar to extant macrothelids, suggesting that they probably have similar retreat construction behavior, habitat preference, and mating position to their living relatives.

Coccoidea (Hemiptera, Sternorrhyncha) are widely distributed and agriculturally significant insects known for their distinctive morphology and biological traits. The Coccoidea are often called scales or mealybugs because many species have a shell‐like covering resembling a scale or are covered with mealy wax. Knowledge of scale insects beyond the female adult stage is limited, partly because other life stages are less conspicuous, shorter‐lived, and less impactful on host plants. This complicates accurate classification, further compounded by limited molecular phylogenetic studies. This study presents the first phylogenetic analyses combining genome and transcriptome sequence data. We sequenced five whole genomes and one transcriptome from Pseudococcidae and integrated these new genome‐scale data with existing genome and transcriptome sequences to perform phylogenomic analysis of scale insects. The analysis yielded robustly supported relationships within Coccoidea, resolving several high‐level relationships. The current genome‐scale data support the monophyly of Monophlebidae, Pseudococcidae, Kerriidae, and Diaspididae, while not supporting the monophyly of Coccidae and Eriococcidae. Bayesian inferences using site‐heterogeneous models corroborated Pseudococcidae as the sister group of all other neococcoid families. Within Pseudococcidae, two subfamilies, Phenacoccinae and Pseudococcinae, were supported. At the tribe level, Phenacoccini was found to be monophyletic, whereas Planococcini, Trabutinini, and Pseudococcini were not.

A full understanding of local adaptation at the genomic level will help to elucidate its role in the differentiation between closely related species. This study focused on rice seed bugs sister species (Leptocorisa chinensis and Leptocorisa oratoria), which are native to East Asia and are notorious pests targeting growing rice spikelets. East Asia is a region where diverse geology and fluctuating climate are known to have profound impacts on organisms. In this study, single nucleotide polymorphisms (SNPs) from double-digest restriction site-associated DNA sequencing and geographic distribution information were used to investigate phylogeography and assess the environmental contribution to genetic variation. We found clear genetic differentiation between sister species, but a lack of genetic structure within species because of their long-distance dispersal ability. The demographic model involved a scenario in which divergence in isolation (~0.6 Ma) was followed by secondary contact (~7 kya). The initial divergence may have been caused by the intensification of the East Asian monsoon during the Pleistocene climate oscillation. The historical demography indicated that the effective population size (N_e) showed an evident increase from 9 to 7 kya, which may be related to rice domestication and extensive human cultivation during the Holocene. We also detected a significant correlation between genetic and environmental distance, and the niche difference occupied between them. Temperature-related variables were ranked as the main factors for the difference, and 410 selective SNPs involved in adaptation were identified. The Nanling Mountains in southern China serve as a geographical boundary between them and act as an ecological barrier belt that promotes local environmental adaptation. Our study demonstrates that historical climate change and local adaptation by climate-imposed selection shape the phylogeographical patterns of sister species.

Based on several earwigfly specimens with well-preserved mouthparts of Meropeidae from mid-Cretaceous Burmese amber, a detailed, initial analysis was conducted of the structure of Mesozoic meropeids. Compared to the singularly flattened mandible of modern meropeids, the new specimens reveal that Mesozoic representatives had two distinct types of mandibles: blade-shaped and scoop-shaped. Current fossil evidence indicates that during the Mesozoic Era, Meropeidae displayed sexual dimorphism that was reflected in the structure of their mandibles. This structural difference may indicate that about 99 million years ago, meropeids had a more complex diet than extant confamilial taxa. Phylogenetic results suggest that Torvimerope gen. nov., along with Burmomerope, two extinct genera, form a clade and that are the sister taxon to crown-group Meropeidae. The new material offers new possibilities for inferring the feeding habits and mating behavior of early Meropeidae.

During the Cretaceous period, the lacewing superfamily Mantispoidea, with an assemblage of species possessing raptorial forelegs, have undergone a rapid species radiation, characterized by abundant species richness and high morphological plasticity. Nevertheless, the morphology and early evolution of the specialized predatory organ around the time of its origin in raptorial Mantispoidea have been poorly documented due to the rarity of fossil evidence, especially for the pre-Cretaceous fossils. Herein, a new genus and new species, that is Archarhachiberotha longitarsa Wang, Ren et Wang gen. et sp. nov., was described from the Middle Jurassic Jiulongshan Formation of northeastern China. This new genus was characterized by the remarkable raptorial forelegs, that is, typically elongated coxa, relatively less-swollen femur and rudimentary small femoral spines, and well-developed tarsi. Considering the peculiar morphological combination and antiquity of the new genus, it was assigned to be a stem-group lineage of Mantispoidea. Also, the detailed analyses of morphology and biological functions of raptorial forelegs were made to conclude that the new genus evolved into an unknown but primitive raptorial type that was distinctly different from the extant morphological features and raptorial mechanisms. In addition, the evolutionary tendency of raptorial Mantispoidea herein summarized highlights morphological diversity and disparity between fossil and extant representatives, and provides a rare case to explore the entire evolutionary history of a specialized structure in one lineage.

Quaternary climate fluctuations and complex mountain systems had a prominent impact on the genetic diversification and speciation of montane organisms. However, the genetic imprints of the interplay between past climate events and rugged relief on montane species remain largely unresolved. Here, we analyzed the phylogeny, population structure, divergence time, demographic simulations, and ecological niche modeling of the montane scorpionfly Cerapanorpa obtusa (Cheng) from 36 populations in the mountains of central China (MCC) using three mitochondrial and two nuclear genes to explore its evolutionary history. The results show that C. obtusa originated from the Minshan Mountains, and currently consists of six genetically fragmented lineages that diverged 1.25-0.52 Ma. Four minor lineages (S1-S4) are confined to the topographically rugged Minshan Mountains, and two major lineages (NW and NE) are widely distributed in the northern MCC with relatively homogeneous landscapes. The Minshan Mountains are likely interglacial microrefugia for C. obtusa, and as spatial buffers in response to past climate changes. These findings provide some evidence that the interplay between climate changes and rugged relief may play a significant role in shaping the distinct phylogeographical pattern of cold‐adapted montane insects. These results would also seem to suggest the importance of topographically rugged mountain systems in the conservation of evolutionary diversity and endemic species.

Neuroptera, as a small relic group of Insecta undergoing a rapid species diversification during the Mesozoic Era, is known by diverse extinct endemic lineages preserved as impression fossils and in amber. The current understanding of Mesozoic neuropterans' diversity has mainly focused on the adults, because the contemporaneous larvae have been fairly rare especially for the Jurassic lacewings. Herein, a new giant lacewing larva, Natator giganteus gen. et sp. nov., is described from the Middle Jurassic Daohugou Beds of China. The remarkable larva is characterized by its impressively large body size, distinctively elongated cervix, and presence of swimming hairs on legs, which provide direct evidence to reveal an aquatic habit for the Jurassic lacewing larva. The morphological analysis indicates this giant larva would have probably inhabited the benthic environments of Jurassic montane rivers and streams. In addition, its morphological specialization suggests that it might have adopted an ambush predation strategy to catch its prey. The finding enhances our knowledge of the species diversity and morphological plasticity for the Jurassic lacewing larvae, and reveals that the aquatic lineages of Neuroptera exhibited dramatically structural and ecological convergence across the evolutionary process.

The Cucujiformia, with remarkable morphological, ecological, and behavioral diversity, is the most evolutionarily successful group within Coleoptera. However, the phylogenetic relationships among superfamilies within Cucujiformia remain elusive. To address the issues, we conducted a transcriptome-based macro-evolutionary study of this lineage. We sequenced the genomes and transcriptomes of three species from the superfamily Curculionoidea (two from Curculionidae and one from Brentidae), and obtained a data set of more than 569 990 amino acid alignments from 143 species of Cucujiformia. With the most complete collection of whole genomes and transcriptomes so far, we compared the performance of different data matrices with universal-single-copy orthologs (USCO). The resultant trees based on different data sets were consistent for the majority of deep nodes. Two USCO amino acid matrices (i.e., USCO75 and USCO750-abs80) provided well-resolved topology. The analyses confirm that Cucujoidea sensu Robertson et al. 2015 is a nonmonophyletic group, consisting of Erotyloidea, Nitiduloidea, and Cucujoidea sensu Cai et al. 2022. Moreover, Erotyloidea is the early-diverging group, followed by the clade Nitiduloidea. The preferred topologies supported a “basal” split of Coccinelloidea from the remaining superfamilies, and Cleroidea formed the second splitting group. The following phylogeny was supported at the superfamily level in Cucujiformia: (Coccinelloidea, (Cleroidea, ((Lymexyloidea, Tenebrionoidea), (Erotyloidea, (Nitiduloidea, (Cucujoidea, (Chrysomeloidea, Curculionoidea))))))). Our comprehensive analyses recovered well-resolved higher-level phylogenetic relationships within the Cucujiformia, providing a stable framework for comprehending its evolutionary history.

A robust and stable phylogenetic framework is a fundamental goal of evolutionary biology. As the third largest insect order, Lepidoptera (butterflies and moths) are central to terrestrial ecosystems and serve as important models for biologists studying ecology and evolutionary biology. However, for such an insect group, the higher-level phylogenetic relationships among its superfamilies remain poorly resolved. Here, we increased taxon sampling among Lepidoptera (37 superfamilies and 68 families containing 263 taxa), obtaining a series of amino-acid data sets from 69 680 to 400 330 aa in length for phylogenomic reconstructions. Using these data sets, we explored the effect of different taxon sampling with significant increases in gene loci on tree topology using maximum-likelihood (ML) and Bayesian inference (BI) methods. Moreover, we also tested the effectiveness of topology robustness among the three ML-based models. The results demonstrated that taxon sampling is an important determinant in tree robustness of accurate phylogenetic estimation for species-rich groups. Site-wise heterogeneity was identified as a significant source of bias, causing inconsistent phylogenetic positions among ditrysian lineages. The application of the posterior mean site frequency (PMSF) model provided reliable estimates for higher-level phylogenetic relationships of Lepidoptera. Phylogenetic inference presented a comprehensive framework among lepidopteran superfamilies, and revealed some new sister relationships with strong supports (Papilionoidea is sister to Gelechioidea, Immoidea is sister to Galacticoidea, and Pyraloidea is sister to Hyblaeoidea, respectively). The current study provides essential insights for future phylogenomic investigations in species-rich lineages of Lepidoptera and enhances our understanding on phylogenomics of highly diversified groups.