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Field‐collected specimens were used to obtain nine high‐quality genome assemblies from a total of 10 insect species native to prairies and savannas of central Illinois (USA): Mellilla xanthometata (Lepidoptera: Geometridae), Stenolophus ochropezus (Coleoptera: Carabidae), Forcipata loca (Hemiptera: Cicadellidae), Coelinius sp. (Hymenoptera: Braconidae), Thaumatomyia glabra (Diptera: Chloropidae), Brachynemurus abdominalus (Neuroptera: Myrmeleontidae), Catonia carolina (Hemiptera: Achilidae), Oncometopia orbona (Hemiptera: Cicadellidae), Flexamia atlantica (Hemiptera: Cicadellidae) and Stictocephala bisonia (Hemiptera: Membracidae). Sequencing library preparation from single specimens was successful despite extremely small DNA yields (<0.1 μg) for some samples. Additional sequencing and assembly workflows were adapted to each sample depending on the initial DNA yield. PacBio circular consensus (CCS/HiFi) or continuous long reads (CLR) libraries were used to sequence DNA fragments up to 50 kb in length, with Illumina sequenced linked‐reads (TellSeq libraries) and Omni‐C libraries used for scaffolding and gap‐filling. Assembled genome sizes ranged from 135 MB to 3.2 GB. The number of assembled scaffolds ranged from 47 to >13,000, with the longest scaffold per assembly ranging from ~23 to 439 Mb. Genome completeness was high, with BUSCO scores ranging from 85.5% completeness for the largest genome (Stictocephala bisonia) to 98.8% completeness for the smallest genome (Coelinius sp.). The unique content was estimated using RepeatMasker and GenomeScope2, which ranged from 50.7% to 75.8% and roughly decreased with increasing genome size. Structural annotation predicted a range of 19,281–72,469 protein models for sequenced species. Sequencing costs per genome at the time ranged from US$3–5k, averaged ~1600 CPU‐hours on a high‐performance cluster and required approximately 14 h of bioinformatics analyses with samples using PacBio HiFi data. Most assemblies would benefit from further manual curation to correct possible scaffold misjoins and translocations suggested by off‐diagonal or depleted signals in Omni‐C contact maps. [ABSTRACT FROM AUTHOR]

Recent phylogenetic analyses of anchored‐hybrid, transcriptomic and morphological data have consistently recovered a clade comprising the three previously recognized families of treehoppers (Hemiptera), Aetalionidae, Melizoderidae and Membracidae, as well as two groups traditionally included in the leafhopper family Cicadellidae as subfamilies Megophthalminae and Ulopinae. To reconstruct the phylogeny of these two groups of treehopper‐like leafhoppers, maximum likelihood and multi‐species coalescent analyses were performed on a molecular DNA dataset consisting of ~700 anchored hybrid loci representing 84 terminal taxa. Analyses based on different dataset subsets and approaches yielded largely congruent topologies, although the relationships among Megophthalminae, Ulopinae and treehoppers are still unstable. The monophyly of both subfamilies is strongly supported, but several tribes, including Agalliini, Cephalelini, Megophthalmini and Ulopini, are recovered as non‐monophyletic. The origin of Megophthalminae and Ulopinae was estimated as early Cretaceous (~140 million years ago), and the divergence within each subfamily began in the mid‐Cretaceous. Continental‐scale biogeographic structure is evident in these two groups, with genera occurring on the same continent tending to group together regardless of tribal placement, suggesting that extensive morphological convergence occurred among faunas inhabiting different regions. Ancestral microhabitat reconstruction suggested that megophthalmine and ulopine leafhoppers originally lived on trees or shrubs and later several groups evolved independently to inhabit leaf litter and soil. Convergent modifications of the ocelli, forewings and hindwings accompanied changes in microhabitat preference. [ABSTRACT FROM AUTHOR]

The phylogenetic relationships among major lineages of the globally distributed leafhopper subfamily Coelidiinae were reconstructed by analysis of 2903 nucleotide positions from two mitochondrial genes (COI and 16S), four nuclear genes (28S, H3, H2A and Wingless) and 102 discrete morphological characters, compiled for 86 species representing 52 genera within 9 coelidiine tribes broadly representative of the world fauna in addition to 12 outgroup taxa. Maximum likelihood and Bayesian analyses yielded well‐resolved phylogenetic estimates that were highly congruent with most branches receiving strong support. The results indicate Coelidiinae sensu stricto (=Coelidiinae sensu lato without Equeefini and Macroceratogoniini), Thagriini, Tharrini, Tinobregmini and Equeefini are monophyletic. However, the two largest tribes, Coelidiini and Teruliini, are paraphyletic, as well as Youngolidiini and most genera of Oriental Coelidiini. Fossil‐calibrated molecular divergence time analysis indicates that the Coelidiinae sensu stricto originated ca. 149 Ma, prior to the complete separation of the Gondwanan continents, and the tribe‐level lineages diverged between the Lower and Upper Cretaceous (92.77–138.03 Ma). The major lineages of Coelidiinae arose in the Oriental and Neotropical regions, and Oriental Coelidiini arose as a result of dispersal and colonisation from the Afrotropical region. [ABSTRACT FROM AUTHOR]

Cicadellidae (leafhoppers) may be the most diverse and abundant insect herbivores in terrestrial ecosystems worldwide, with more than 23,000 described species in 20 extant subfamilies. Although prior studies have supported the monophyly of most recognized subfamilies, relationships among these groups remain inconsistently resolved and previous molecular phylogenies have failed to support the monophyly of a few subfamilies. To help address this deficiency, we combined 24 new complete mitogenomes representing 6 previously unsequenced subfamilies and 13 tribes with previously available data to create a dataset of 79 cicadellid taxa representing 16 subfamilies for phylogenetic analysis. The new analyses confirm that leafhopper mitochondrial genomes are highly conservative in overall structure, with only a few rare rearrangements of tRNAs. All phylogenetic analyses consistently supported the monophyly of previously recognized cicadellid tribes for which more than 1 representative was included and all of the included subfamilies were also consistently recovered as monophyletic with the exception of Aphrodinae and Eurymelinae. Bayesian inference and Maximum Likelihood analyses with site-homogeneous models are only slightly affected by nucleotide compositional heterogeneity and yield more stable phylogenetic relationships of family-group taxa than analyses with a heterogeneous-site mixture model using PhyloBayes. Molecular divergence time estimates indicate that the main lineages of Cicadellidae, most corresponding to recognized subfamilies, diverged during the Cretaceous period (93–121 Mya). [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Simple Summary: The mitochondrial genome of insects has been widely used in studies of molecular evolution, population genetics, phylogenetics, and species identification due to its small size (approximately 14–20 kb), relatively high evolutionary rate, low levels of recombination, and high genome copy numbers. In this study, 13 complete mitogenomes of Chiasmini, a diverse group of grassland leafhoppers, were sequenced and analyzed for the first time. The phylogenetic position of Chiasmini within leafhoppers and the phylogenetic relationships among Chiasmini genera were reconstructed. The results show that all 13 mitogenomes are composed of a circular, double-stranded molecule that consists of 37 genes with a total length ranging from 14,805 to 16,269 bp and a variable number of non-coding A + T-rich regions. The gene size, order, arrangement, base composition, codon usage, and secondary structure of tRNAs in these newly sequenced mitogenomes of 13 species are highly conserved in Chiasmini. Phylogenetic analysis of the newly sequenced genomes plus representatives of other tribes and subfamilies of Cicadellidae recover all included subfamilies of Cicadellidae and tribes of Deltocephalinae as monophyletic, except Athysanini and Opsiini in Deltocephalinae, which are paraphyletic in agreement with some other recent studies. Chiasmini form a monophyletic group consisting of seven monophyletic genera arranged as follows: ((Zahniserius + (Gurawa + (Doratura + Aconurella))) + (Leofa + (Exitianus + Nephotettix))). The grassland leafhopper tribe Chiasmini (Cicadellidae: Deltocephalinae) presently comprises 324 described species worldwide, with the highest species diversity occurring in the Nearctic region but a greater diversity of genera occurring in the Old World. In China, this tribe comprises 39 described species in 11 genera, but the fauna remains understudied. The complete mitogenomes of three species of this tribe have been sequenced previously. In order to better understand the phylogenetic position of Chiasmini within the subfamily Deltocephalinae and to investigate relationships among Chiasmini genera and species, we sequenced and analyzed the complete mitogenomes of 13 species belonging to seven genera from China. Comparison of the newly sequenced mitogenomes reveals a closed circular double-stranded structure containing 37 genes with a total length of 14,805 to 16,269 bp and a variable number of non-coding A + T-rich regions. The gene size, gene order, gene arrangement, base composition, codon usage, and secondary structure of tRNAs of the newly sequenced mitogenomes of these 13 species are highly conserved in Chiasmini. The ATN codon is commonly used as the start codon in protein-coding genes (PCGs), except for ND5 in Doratura sp. and ATP6 in Nephotettix nigropictus, which use the rare GTG start codon. Most protein-coding genes have TAA or TAG as the stop codon, but some genes have an incomplete T stop codon. Except for the tRNA for serine (trnS1(AGN)), the secondary structure of the other 21 tRNAs is a typical cloverleaf structure. In addition to the primary type of G–U mismatch, five other types of tRNA mismatches were observed: A–A, A–C, A–G, U–C, and U–U. Chiasmini mitochondrial genomes exhibit gene overlaps with three relatively stable regions: the overlapping sequence between trnW and trnC is AAGTCTTA, the overlapping sequence between ATP8 and ATP6 is generally ATGATTA, and the overlapping sequence between ND4 and ND4L is generally TTATCAT. The largest non-coding region is the control region, which exhibits significant length and compositional variation among species. Some Chiasmini have tandem repeat structures within their control regions. Unlike some other deltocephaline leafhoppers, the sequenced Chiasmini lack mitochondrial gene rearrangements. Phylogenetic analyses of different combinations of protein-coding and ribosomal genes using maximum likelihood and Bayesian methods under different models, using either amino acid or nucleotide sequences, are generally consistent and also agree with results of prior analyses of nuclear and partial mitochondrial gene sequence data, indicating that complete mitochondrial genomes are phylogenetically informative at different levels of divergence within Chiasmini and among leafhoppers in general. Apart from Athysanini and Opsiini, most of the deltocephaline tribes are recovered as monophyletic. The results of ML and BI analyses show that Chiasmini is a monophyletic group with seven monophyletic genera arranged as follows: ((Zahniserius + (Gurawa + (Doratura + Aconurella))) + (Leofa + (Exitianus + Nephotettix))). [ABSTRACT FROM AUTHOR]

BACKGROUND: Tribe Zyginelline leafhoppers can transmit plant viruses and are important pests that affect agriculture, forestry, and animal husbandry, causing serious economic losses. The potential distribution patterns of Zyginellini will change under climate change. Therefore, the best‐performing random forest and maximum entropy models among 12 commonly used ecological niche models, alongside an ensemble model, were selected to predict the changes in habitat suitability distribution of Zyginellini under current and future climate scenarios [represented by two shared socio‐economic pathways (SSPs), namely SSP126 and SSP585, for three periods (2050s, 2070s, and 2090s)] in China and the Indo‐China Peninsula for the first time. RESULTS: The results revealed that the distribution of Zyginellini was mainly dominated by minimum temperature of coldest month. Under current and future climate scenarios, Zyginellini was mostly distributed southeast of the 400 mm equivalent precipitation line in China, and Vietnam. Under the future SSP126 scenario, the alert areas will mainly be concentrated in Hunan, Jiangxi, Zhejiang, Anhui, and Hebei in China, alongside Myanmar and Thailand in the Indo‐China Peninsula. Meanwhile, in the SSP585 scenario, the alert areas in China will increase, whereas there will be little change in the Indo‐China Peninsula. Interestingly, from the current to the future, the cores of Zyginelline distribution occurred around rivers and mountains, and shifted from Guizhou along the Yuanjiang River system to higher latitudes in Hunan. CONCLUSION: Zyginellini prefers higher latitude river‐mountain systems under climate change. Our results will contribute to effective pest control strategies and biogeographical research for Zyginellini alongside other Cicadellidae insects. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The genus Chanohirata Hayashi & Machida, including the herein synonymized monotypic genus Reticuluma Cheng & Li, is the second most speciose genus in the tribe Penthimiini after Penthimia Germar and is almost exclusively endemic to China. This study presents the first phylogeny of Chanohirata based on three mitochondrial markers (cytochrome c oxidase subunit I and II and 16S ribosomal RNA) and one nuclear fragment (28S ribosomal RNA). Reticulumasyn. n. is recovered nested within Chanohirata with strong support. Reticuluma is, therefore, proposed as a junior synonym of Chanohirata, and a new combination is proposed: Chanohirata citrana (Cheng & Li) comb. n. Molecular species delimitation analyses were conducted by combining six molecular delimitation methods with morphological evidence. The results of the species delimitation analyses confirm the status of eight described species of Chanohirata and support the recognition of three new species: Chanohirata cornicula Wang & Zhang sp. n., Chanohirata elongata Wang & Zhang sp. n. and Chanohirata serrata Wang & Zhang sp. n. Molecular dating and biogeographic analyses suggest that Chanohirata likely originated during the late Eocene in southern China. During the late Miocene to early Pleistocene, the uplift of the Himalayas and Tibetan Plateau and climatic oscillations probably triggered several dispersal and vicariance events in Chanohirata lineages, leading to most speciation events. [ABSTRACT FROM AUTHOR]

Insects have highly variable reproductive systems, reflecting a diversity of reproductive strategies and adaptations. Such variation has been widely used to classify and estimate phylogenetic relationships. Here, the morphology and ultrastructure of the internal reproductive systems of two leafhopper species are described and illustrated, using both light and transmission electron microscopy, and representing two tribes of Deltocephalinae: in Chiasmini, Nephotettix cincticeps (Uhler, 1896), and in Deltocephalini, Deltocephalus vulgaris (Dash & Viraktamath, 1998). Tables comparing the morphology of male and female internal reproductive structures of these studied species are provided and indicate that the main differences are in the relative shapes, sizes, and colors of these structures. The overall structure and organization, including details of the ultrastructure, of these two leafhopper species' male and female internal reproductive systems are very similar to those of previously studied leafhoppers. The main differences observed among species include the number of testicular follicles, the relative position of seminal vesicles and the degree of development of the accessory glands in the male, the number of ovaries, and the shape and color of the vagina and spermatheca in the female. [ABSTRACT FROM AUTHOR]