Comparative mitochondrial genome analysis of two biting midges, Dasyhelea ludingensis and Forcipomyia (Lasiohelea) taiwana (Diptera: Ceratopogonidae)

Complete mitogenome of Pelecorhynchus vulpes (Macquart) (Diptera: Pelecorhynchidae) and its phylogenetics implications on Tabanomorpha

The infraorder Tabanomorpha represents a key lineage within the lower Brachycera; however, the phylogenetic placement of several families, including Pelecorhynchidae, remains incompletely resolved owing to the lack of mitogenomic data. In this study, we sequenced and characterized the complete mitochondrial genome of Pelecorhynchus vulpes (Macquart, 1850), representing the first mitogenome reported for both the genus and the family. The circular genome is 15,390 bp in length and comprises a typical set of 37 genes, including 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and a control region. The genome exhibits a strong A+T bias (78.4%) and retains the ancestral insect gene arrangement. Comparative analyses revealed a high degree of structural conservation with other Tabanomorpha, particularly in Tabanidae and Athericidae. Phylogenetic analyses based on concatenated mitochondrial protein-coding and ribosomal genes, using both Bayesian inference and maximum likelihood approaches, support Pelecorhynchidae as a sister lineage to Athericidae and Tabanidae. These findings provide new genomic evidence supporting the phylogenetic placement of Pelecorhynchidae and contribute to understanding of the evolutionary relationships within Tabanomorpha. Additionally, the phylogenetic affinity between the Chilean and Australasian representatives of Pelecorhynchus is consistent with a Gondwanan origin for the group, although alternative scenarios, such as long-distance dispersal, cannot be excluded. This study highlights the importance of mitogenomic data from underrepresented lineages and provides information for new integrative studies that combine mitochondrial and nuclear data to resolve the evolutionary history of Tabanomorpha.

The complete mitochondrial genome of Acanthaspis geniculata (Hsiao, 1976) (Hemiptera: Reduviidae) and its phylogenetic analyses

Abstract The genus Acanthaspis (Hemiptera: Reduviidae) comprises predatory insects of ecological importance, yet mitochondrial genomic resources for this group remain limited. Here, we present the complete mitochondrial genome of Acanthaspis geniculata (Hsiao, 1976). The mitogenome is 16,226 bp in length and contains the standard set of 37 mitochondrial genes (13 protein-coding genes, 2 rRNA genes, and 22 tRNA genes), along with a control region (D-loop). The nucleotide composition is A (40.4%), T (29.6%), C (17.9%), and G (12.1%), with an overall AT content of 70.0%. Phylogenetic analyses based on partitioned mitochondrial datasets strongly support the monophyly of the subfamily Reduviinae and reveal that A. geniculata forms a close sister-group relationship with A. ruficeps and A. pedestris. This study provides a fundamental mitogenomic resource for future evolutionary and systematic studies of the Reduviidae.

The complete mitochondrial genome of Pammene nemorosa (Lepidoptera, Tortricidae) and its phylogenetic placement within Grapholitini

The intergeneric attraction of Pammene nemorosa to sex pheromone traps targeting the Oriental fruit moth, Grapholita molesta (Lepidoptera: Tortricidae), may compromise the reliability of pest monitoring in apple orchards, yet the evolutionary context of this behavioral overlap remains unclear. Here, we sequenced and characterized the first complete mitochondrial genome (mitogenome) of P. nemorosa and assessed its phylogenetic position within the tribe Grapholitini. The circular mitogenome is 15,457 bp long and contains the canonical set of 37 genes, including 13 protein-coding genes, 22 transfer RNA genes, and two ribosomal RNA genes, with a gene order typical of ditrysian Lepidoptera. The genome exhibits a pronounced A + T bias (80.1%), and its 484-bp control region contains a tandem duplication of an approximately 215-bp sequence unit, with each repeat copy marked by an ATAGA motif. Phylogenetic analyses based on Neighbor-Joining, Maximum Likelihood, and Bayesian Inference consistently recovered P. nemorosa as sister to the Grapholita clade (G. dimorpha + G. molesta), with strong Bayesian support (posterior probability = 0.999), highlighting a potential discordance between its mitochondrial phylogenetic position and its current morphological classification within Pammene. These findings establish the first complete mitogenomic resource for P. nemorosa and provide a phylogenetic framework for interpreting its close evolutionary affinity with Grapholita species. Although mitochondrial data alone cannot establish the functional mechanisms underlying heterospecific pheromone attraction, the genomic resource established here provides a baseline for future integrative studies combining nuclear genomics, transcriptomics, and chemical ecology, and contributes to a broader understanding of the evolutionary relationships and ecological interactions within Grapholitini.

Comparative analysis of the mitochondrial genome of Androctonus crassicauda Olivier, 1807 (Scorpiones, Buthidae) with phylogenetic implication

Characterization of mitochondrial genomes in six newly sequenced species and analysis of gene rearrangements across Encyrtidae (Hymenoptera, Chalcidoidea)

Abstract Encyrtidae plays a significant ecological and agricultural role in the biological control of pests. However, the limited mitogenome data and unresolved phylogenetics impede the evolutionary research. We sequenced and annotated the complete mitogenomes of six Encyrtidae species (Blastothrix speciosa, Encyrtus aurantii, Lamennaisia ambigua, Lamennaisia nobilis, Cheiloneurus chinensis, and Tassonia gloriae). All six mitogenomes exhibit the typical circular structure, containing 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), two ribosomal RNAs (rRNAs), and one control region (CR). They show a strong AT bias (81.3–83.8%) and vary in length from 15,397 bp to 17,160 bp. Conserved family-specific gene rearrangements, likely synapomorphic for Encyrtidae, were identified in this study using Drosophila yakuba as the ancestral reference species. Species-specific variations, mainly in tRNAs and a few PCGs, appear shaped by positive selection, tRNA structural flexibility, and host adaptation, a pattern that is consistent with the “duplication-random loss” model. Phylogenetic analyses based on the concatenated sequences of 13 PCGs via Maximum Likelihood and Bayesian Inference yielded highly congruent topologies, confirming Encyrtus monophyly and the congruence between molecular clustering and morphological taxonomy. This study enriches Encyrtidae mitogenome resources, clarifies the evolutionary rules and gene rearrangements mechanisms, and provides molecular evidence for Encyrtidae systematics and adaptive evolution research.

New mitogenomic evidence for the phylogeny of Siphonaptera: insights from Callopsylla dolabris and Oropsylla silantiewi

As important vectors of infectious diseases such as plague, fleas require accurate classification and phylogenetic analysis, which are essential for public health prevention and control. However, complete mitochondrial genome resources for Siphonaptera in public databases are still extremely scarce. In this study, the complete mitochondrial genomes of C. dolabris and O. silantiewi, collected from the high-altitude region in Qinghai Province, were sequenced and characterized for the first time using next-generation sequencing technology. The results showed the two mitogenomes were 17,104 bp and 15,914 bp in length, respectively. Both mitogenomes exhibited significant A+T bias and a strong preference for A/U-ending codons. Selective pressure analysis (Ka/Ks) indicated that mitochondrial protein-coding genes (PCGs) of fleas are predominantly under purifying selection. Phylogenetic reconstructions based on 39 mitogenomic sequences from 36 flea species revealed that Ceratophylloidea was robustly supported as monophyletic. At the family level, neither Ceratophyllidae nor Leptopsyllidae formed a strictly monophyletic group in the present dataset. Pulicidae was recovered as a well-supported monophyletic clade. Both newly sequenced species were placed within Ceratophyllidae. This study not only expands the available mitogenomic resources for Siphonaptera, but also provides new insights into nucleotide composition patterns and phylogenetic relationships within the order.