Comparisons of mitogenomes are widely used for species identification and to explore the phylogenetic relationship among insect taxa. Batracomorphus is the third most diverse and widely distributed genus in the Cicadellidae (Hemiptera). However, there have been no analyses of genome structure and phylogenetic relationships within the genus.To compensate for the paucity of genomic information in this genus, we sequenced novel complete mitochondrial genomes of 11 Batracomorphus species and combined these with 23 previously sequenced mitochondrial genomes to perform structural comparisons and phylogenomic studies. Our results reveal generally conserved mitogenome organization, with one case of tRNA gene rearrangement, with trnI-trnQ reversed to trnQ-trnI when compared with the ancestral arrangement. Analysis of the ratio of nonsynonymous (Ka) to synonymous substitutions (Ks) showed ATP8 is the fastest and COI is the slowest evolving gene. ND2 and ND6 have highly variable nucleotide diversity, whereas COI and ND1 exhibit the lowest diversity. Phylogenetic analysis of nucleotide sequences grouped Batracomorphus species into a clade within the subfamily Iassinae. Within Batracomorphus, 3 clades were reconstructed consistent with the observed gene rearrangement, indicating that such rearrangements can serve as reliable molecular markers supporting phylogenetic hypotheses. These clades also correspond to clusters of species recovered by morphometric analysis of aedeagal shape, suggesting that characters of the male genitalia traditionally used for species delimitation are phylogenetically informative. Molecular divergence time estimates indicate that most speciation events within Batracomorphus occurred between the Paleogene and Neogene.This study provides insight into the population genetics, molecular biology, phylogeny, and morphological evolution of the leafhopper subfamily Iassinae and its largest genus, Batracomorphus.

Gerromorpha Popov, 1971 is a fascinating and diverse insect lineage that evolved about 200 Mya to spend their entire life cycle on the air–water interface and have since colonized all types of aquatic habitats. The subfamily Halobatinae Bianchi, 1896 is particularly interesting because some species have adapted to life on the open ocean—a habitat where insects are very rarely found. Several attempts have been made to reconstruct the phylogenetic hypotheses of this subfamily, but the use of a few partial gene sequences recovered only a handful of well-supported relationships, thus limiting evolutionary inferences. Fortunately, the emergence of high-throughput sequencing technologies has enabled the recovery of more genetic markers for phylogenetic inference. We applied genome skimming to obtain mitochondrial and nuclear genes from low-coverage whole-genome sequencing of 85 specimens for reconstructing a well-supported phylogeny, with particular emphasis on Halobatinae. Our study confirmed that Metrocorini Matsuda, 1960, is paraphyletic, whereas Esakia Lundblad, 1933, and Ventidius Distant, 1910, are more closely related to Halobatini Bianchi, 1896, than Metrocoris Mayr, 1865, and Eurymetra Esaki, 1926. We also found that Ventidius is paraphyletic and in need of a taxonomic revision. Ancestral state reconstruction suggests that Halobatinae evolved progressively from limnic to coastal habitats, eventually attaining a marine lifestyle, especially in the genus Halobates Eschscholtz, 1822, where the oceanic lifestyle evolved thrice. Our results demonstrate that genome skimming is a powerful and straightforward approach to recover genetic loci for robust phylogenetic analysis in non-model insects.

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Animals exhibit a variety of strategies to avoid predation; spiders are no exception. We explored whether web-building spiders that differ in the architecture of their webs exhibit morphologies or behaviors suggestive of antipredator strategies that trade-off with the degree of protection offered by their webs. Spiders build webs of 3 types: the more protected tangles and sheet-and-tangles, which are three-dimensional (3D), and the more exposed orbs, which are two-dimensional (2D), both with or without a refuge. We hypothesize that spiders whose webs offer greater protection—a 3D architecture or a refuge—will be less likely to be armored or brightly colored when compared to spiders without these protections. We collected data on 446 spiders and their webs in 2 lowland tropical rainforest sites. We show that 2D web builders with no refuges tended to be brightly colored (background contrasting) and spiny (spiky), whereas those with refuges tended to blend against the background of their refuges. 3D web builders, on the other hand, were neither cryptic nor brightly colored nor armored but were more likely to drop out of the web upon simulated predator contact. These results support the hypothesis that web-building spiders tend to be protected either through the architecture of their webs or their morphology and behavior, suggesting a trade-off between different types of antipredator strategies.

The superfamily Dryopoidea is a diverse group of beetles with a mixture of aquatic, semiaquatic, and terrestrial life histories. These beetles exhibit remarkable morphological diversity, particularly in the larval stages, which is likely associated with their repeated adaptation to aquatic habitats. The phylogenetic relationships among Dryopoidea families and subfamilies are controversial, as phylogenetic analyses based on morphology have failed to propose robust and consistent hypotheses. However, recent molecular phylogenetic studies have provided better resolution for the interfamilial relationships and suggested the non-monophyly of a few families. In this study, we conducted phylogenetic analyses of Dryopoidea obtained in Japan along with other groups in the Elateriformia (Byrrhoidea, Dascilloidea, Buprestoidea, and Elateroidea) using sequence data from ultraconserved elements with the maximum-likelihood method and species-tree analysis based on a multispecies coalescent model. Our results show that Dryopoidea is a monophyletic group, not sister to Byrrhoidea. In Dryopoidea, Dryopidae is sister to all other groups, and Psephenidae and Ptilodactylidae are not monophyletic groups. In Psephenidae, Eubrianacinae has clearly diverged from the other subfamilies (Psepheninae, Psephenoidinae, and Eubriinae) and is closely related to Callirhipidae; in Ptilodactylidae, Cladotominae is related to Psephenidae (except Eubrianacinae) + Chelonariidae and separated from the other Ptilodactylidae subfamilies (Anchytarsinae and Ptilodactylinae). Although ML analyses indicated paraphyly of subfamilies in Limnichidae and Psephenidae (except Eubrianacinae), this was resolved in species tree analysis. Our results show that Eubrianacinae and Cladotominae are clearly distinct groups with different origins from other subfamilies of the respective families and can be separated as independent families.

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Ledrinae, an ancient group of leafhoppers with unusual morphology, is diverse and distributed worldwide but its phylogeny remains largely unexplored. The status and relationships among genera of the largest tribe, Ledrini, are here explored using maximum likelihood and Bayesian analyses of DNA sequence data from mitochondrial genomes and partial nuclear genes acquired for 50 species representing 18 genera, plus outgroups from other cicadellid subfamilies. General features of the sequenced mitogenomes are summarized and compared. A novel and stable genetic rearrangement, with large gene spacers and irregular anticodons occurs in the 9 sequenced mitogenomes of Midoria species, and the possible mechanism that gave rise to this change is discussed. This is the first instance of several species of a single leafhopper genus sharing a unique mitochondrial gene rearrangement. Such arrangements appear to be very unusual among leafhoppers and may be of value for future phylogenetic research on this group. We used different data sets and methods to construct a phylogenetic analysis of Ledrini. Results indicated that neither mitogenome nor nuclear gene fragment data adequately resolves phylogenetic relationships within the group but combining them provides a more robust phylogeny of Ledrini. In general, phylogenetic analyses support treatment of Petalocephalini as a junior synonym of Ledrini and support the monophyly of most included genera, although Destinoides, Ledropsis, and Petalocephala appear to be paraphyletic. In addition, 4 new genera and 20 new species are also described and illustrated based on the phylogenetic results and morphological characteristics.

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The aculeate wasp family Sierolomorphidae is a small and enigmatic group including 14 species in 2 extant genera distributed in the Northern Hemisphere. Nothing is known about their biology, although ectoparasitoidism on insects has been speculated. Only 1 fossil genus fromTuronian (Upper Cretaceous) amber was tentatively assigned to this family. The family Sierolomorphidae is recorded from the Early Cretaceous for the first time, representing the earliest occurrence of the family. Orisolemorpha dyscheres Álvarez-Parra and Engel gen. et sp. n. is described and figured from a male in upper Albian amber of San Just in Spain and is distinguished from all other genera in the family. The genus Loreisomorpha is here assigned to a new subfamily, Loreisomorphinae Álvarez-Parra and Engel subfam. n., based on its significant differences in wing venation relative to the remainder of the family. Taxonomic placement of the new genus is discussed, including a key for the fossil sierolomorphid genera. The ecology and biogeography of the family are reviewed. A checklist is provided of all living and fossil Sierolomorphidae.

Mesoraphidiidae is an extinct family of the order Raphidioptera with an evolutionary history that is largely unexplored. Here, we uncovered the evolutionary history of Mesoraphidiidae using phylogenetic comparative approaches, based on an updated morphological dataset, with an additional description of two new genera and species with distinct cephalic elongation, Dracoraphidia brachystigma gen. et sp. nov. and Teratocephala macrostigma gen. et sp. nov., from mid-Cretaceous Myanmar amber. Phylogenetic analysis shows their affinity to the subfamily Alloraphidiinae. Our results show that the radiation of species diversity and morphological disparity of Mesoraphidiidae dates back to the Lower Cretaceous and experienced a distinct peak approximately 130–118 million years ago (Ma).This timeframe aligns with the CretaceousTerrestrial Revolution (KTR), a period from 125 to 80 Ma marked by the proliferation of flowering plants and their interactions with insects.The habitat preference of mesoraphidiid larvae to gymnosperm plants might have led to their extinction during the KTR, with the associated decline of gymnosperm diversity. Despite reduction in the occupation of morphospace by Mesoraphidiinae, there is surprising expansion of morphospace occupation by Alloraphidiinae in the Upper Cretaceous, possibly related to cephalic elongation, which may have enhanced pollen-feeding or predation ability, in response to extrinsic changes to biodiversity and ecosystems during the KTR. This study enriches our understanding of the macroevolution of snakeflies during the Mesozoic and provides new evidence for the impact of the KTR on insects.

Phylogenetic analyses of planthoppers were conducted using a mitogenome dataset to examine the evolutionary relationships of current families based on both maximum likelihood (ML) and Bayesian inference methods. Delphacoidea, including Cixiidae and Delphacidae, and Fulgoroidea, including all other families, were consistently identified as monophyletic groups. However, Nogodinidae displayed a polyphyletic pattern, with various lineages emerging sister to several issidoid families. Variations were observed across different analyses in the positioning of (Dictyopharidae + Fulgoridae) and the relationships of Ricaniidae sister either to Issidae or to (Flatidae + Acanaloniidae). Several statistical tests indicate that the ML topology has the highest level of statistical confidence.The (Dictyopharidae + Fulgoridae) clade is best positioned as sister to (De rbidae + (Achilidae + (Tropiduchidae + other “higher” planthoppers families))) and the Ricaniidae as sister to (Flatidae + Acanaloniidae).With 13 fossil calibration points, origin times for Delphacoidea and Fulgoroidea were dated back to the Late Permian, approximately 257.46 million years ago. Delphacidae and Cixiidae split during the LateTriassic, while Fulgoroidea diversified earlier during the MiddleTriassic. Divergence and diversification times are also provided for all other extant planthopper families.These results suggest that Delphacoidea and Fulgoroidea likely diverged from the older planthopper fossil families prior to the emergence of angiosperms and may have initially fed on gymnosperms and ancient ferns.The diversification of extant planthopper families occurred during the Jurassic and Cretaceous periods, influenced by evolving climatic conditions, the decline in gymnosperms, and the increasing diversity of angiosperm plants.

Stink bugs are invaluable models for macroevolutionary investigations owing to their astonishing ecological and morphological diversity. Nevertheless, such studies have been hampered by the absence of a solid phylogenetic hypothesis. Morphological and molecular studies based on Sanger data have found no consensus for the position of Pentatomidae, and the deep relationships within the family have been poorly resolved. These persistent uncertainties have cast the systematics of stink bugs into the metaphorical realm of a Pandora's Box. Here, I conduct the first phylogenomic study focusing on pentatomids. Using public data, I aimed at testing the power of genome-scale data to resolve phylogenetic relationships within the family and to address the controversial position of the family within Pentatomoidea. Based on a dataset of 40 taxa and over 1,900 proteins, my results indicate the Pentatomidae as the sister group of all remaining families of Pentatomoidea, with an uncertainty of whether Plataspididae is included in this clade. Within Pentatomidae, my analyses confirm some previous findings, such as the monophyly of Asopinae and the relationship between Nezarini and Antestiini. On the other hand, most of the deep relationships within the family were strikingly different from previous works, for example, the Podopinae as the sister group of the Paleartic Carpocorini. My analyses confirm that the addition of massive amounts of data to phylogenetic studies may help achieve better supported trees for the stink bugs and allies. I argue that a solid and stable phylogeny-based classification will only be achieved with increased employment of -omics data.

The subfamily Phimophorinae includes ∼113 species of cryptic assassin bugs found in the Neotropics and Paleotropics. Presumably due to its small size, cryptic coloration, and occurrence in the remote Eastern Arc Mountains (EAM), Porcelloderes impenetrabilis Rédei, 2012 (Heteroptera: Reduviidae: Phimophorinae), was only recently described as the first representative of this subfamily from mainland Africa. Previous morphology-based phylogenetic research on Phimophorinae (then known as Physoderinae or Epiroderinae) recovered Porcelloderes as sister taxon to the remaining epiroderine-lineage of Phimophorinae. Recent fieldwork in Tanzania has resulted in 241 additional specimens of Porcelloderes from 3 EAM) ranges. We used molecular and morphological analyses for these 241 specimens to (i) determine their species identity, (ii) test the phylogenetic position of Porcelloderes within Phimophorinae, and (iii) determine if divergence within Porcelloderes coincides with periods of climate-driven forest fragmentation in the EAM. Specimens from the Kimboza and Nguru Mountains likely represent P. impenetrabilis, but we here describe Porcelloderes harles, n. sp., from the Udzungwa Mountains. Our molecular phylogeny shows Porcelloderes nested within the epiroderine-lineage of Phimophorinae and as sister taxon to a Madagascar clade. We estimate that the epiroderine-lineage diverged from other Phimophorinae ∼44 MYA.The divergence estimates for the 2 Porcelloderes species is ∼15 MYA, consistent with proposed dates for other EAM assassin bugs and a period of forest fragmentation.

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