The control region (CR) of the mitochondrial genome (mitogenome) represents a major noncoding fragment with several special structural features that are thought to be responsible for the initiation of mitogenome transcription and replication. However, few studies have revealed the evolutionary patterns of CR in the phylogenetic context. Here, we explain the characteristics and evolution of CR in Tortricidae, inferred from a mitogenome-based phylogeny. The first complete mitogenomes of the genera Meiligma and Matsumuraeses were sequenced. Both mitogenomes are double-stranded circular DNA molecules with lengths of 15,675 bp and 15,330 bp, respectively. Phylogenetic analyses derived from 13 protein-coding genes and two ribosomal RNAs showed that most tribes, including subfamilies Olethreutinae and Tortricinae, were recovered as monophyletic clades, similar to previous studies based on morphological or nuclear data. Moreover, comprehensive comparative analyses of the structural organization and role of tandem replications on the length variation and high AT content of CR sequences were conducted. The results reveal a significant positive correlation between the total length and AT content of tandem repeats and whole CR sequences in Tortricidae. The structural organization in CR sequences is diverse, even between closely related tribes, which demonstrates the plasticity of the mitochondrial DNA molecule in Tortricidae.

Animal mitochondrial (mt) genomes are typically double-strand circular DNA molecules, but diverse structural variations have been widely found in multiple groups. In parasitic lice (Phthiraptera), the structure of mt genomes varies remarkably across all five suborders. In this study, we reported the complete mt genome of a chicken body louse, Menacanthus cornutus, which has a typical single circular mt chromosome and drastic mt gene rearrangements. This mt genome is 15,693 bp in length, consisting of 13 protein-coding genes, 23 tRNA genes, 2 rRNA genes, and a control region. A comparison with a typical insect mt genome suggested that two highly similar trnM are present in the mt genome of M. cornutus. Moreover, almost every single gene was rearranged, and over half of mt genes were inverted. Phylogenetic analyses inferred from the mt genome sequences supported the monophyly and position of Amblycera. Mapped over the phylogenetic relationships of Amblycera, we identified two inversion events for the conserved gene blocks in Boopidae and Menoponidae. The inverted ND4L-ND4 was likely a synapomorphic rearrangement in Menoponidae. Our study demonstrated the importance of sequencing mt genomes for additional taxa to uncover the mechanism underlying the structural evolution of the mt genome in parasitic lice.

Calliptamus barbarus (Costa, 1836) is a dominant grasshopper species in Xinjiang, characterized by high fecundity, polyphagy, and strong dispersal abilities. To investigate the molecular basis of its environmental sensing, we identified its chemosensory gene repertoire and performed a comparative analysis across six orthopteran species. We obtained 422 sequences across six major families: odorant receptors (ORs), ionotropic receptors (IRs), gustatory receptors (GRs), odorant-binding proteins (OBPs), chemosensory proteins (CSPs), and sensory neuron membrane proteins (SNMPs). Analysis of gene family dynamics identified 74 chemosensory genes associated with significant expansion events, including 40 ORs, 14 IRs, and 20 CSPs. Functional enrichment analysis revealed that these expanded gene families are associated with chemosensory behavior and olfactory transduction. Notably, core functional components such as Orco, SNMP1, and certain antennal IRs remain highly conserved across the six species. These variations in gene family size may represent molecular adaptations for environmental recognition. Our findings identify potential targets for future behavioral interference and sustainable pest management.

Calliptamus barbarus is a dominant pest of desert and semi-desert grasslands in Xinjiang, China, yet its detoxification metabolism gene repertoire and its tissue-level organization remain poorly characterized. Here, we sequenced the transcriptomes of four key detoxification tissues (gastric caeca, midgut, Malpighian tubules and fat body; three biological replicates each) and, using BLAST- and HMMER-based searches against reference proteins from Drosophila melanogaster and Locusta migratoria, identified 1602 detoxification metabolism genes in five families (COE 522, P450 470, UGT 276, ABC 233 and GST 101). Phylogenetic comparison with Locusta migratoria and Schistocerca gregaria showed that the xenobiotic-metabolism subfamilies (CYP3, CYP4, α-esterase, Sigma-GST, UGT305 and ABCB/ABCC) are compositionally overrepresented and species-specifically clustered in C. barbarus, whereas subfamilies serving basic physiological roles are conserved. Among 188 tissue-expressed genes, expression was functionally partitioned across tissues: the gastric caeca dominated Phase II conjugation (GST, UGT) and hydrolysis (COE), whereas the Malpighian tubules dominated Phase I oxidation (P450) and Phase III efflux (ABC). RT-qPCR of 11 tissue-biased genes spanning all five families reproduced the transcriptome direction in 11 of 11 cases (two-sided sign test p = 0.001) and agreed quantitatively with the FPKM fold changes (Pearson r = 0.98), confirming the strongest tissue biases for Ugt49B1 and MRP-PO (gastric caeca and midgut, more than 25-fold). These findings provide a detoxification genes resource and a tissue-level functional map for understanding xenobiotic metabolism and environmental adaptation in C. barbarus.