Sexual selection allows male individuals to adopt different evolutionary strategies in mating system. In this study, we determined whether dominance affected reproductive fitness of male crickets Velarifictorus aspersus during both pre-copulatory and post-copulatory selection when we excluded male–male competition. The results showed that females mated more often with male winners only during the first 2 h after a fight when male winners were more likely to produce courtship songs than losers. However, females did not retain the attached spermatophores of male winners longer than those of male losers, and the fecundity and fertilization success also did not differ significantly between females mated different times with male winners and losers. Instead, the fertilization success was positively correlated with male body weight. These results suggest that a recent wining experience increases reproductive fitness of males during pre-copulatory selection, but females may prefer larger males rather than winners during post-copulatory selection. The incoordination between pre- and post-copulatory selection may allow males to adopt different evolutionary strategies in mating system.

A new species of gall inquiline, Synergus dilatatus sp. nov., is described from Hubei Province, China. Morphological descriptions, photographs and biological information are provided. Mitochondrial cytochrome oxidase (COI) sequences of the new species were newly obtained and a molecular species delimitation analysis of 12 species of Synergus performed using the ASAP method recovered 16 molecular operational taxonomic units, providing support for recognition of the new species. The results also highlight a few conflicts between morphological and molecular species delimitations in Synergus.

Wolbachia (Hertig) (Rickettsiales: Anaplasmataceae) are maternally inherited endosymbiotic bacteria that are widely present in nematodes and arthropods. These endosymbiont bacteria receive significant research attention because they can have important effects on the biology of their hosts. Here, we present the first detailed analyses of Wolbachia in crickets from China, with screening of 23 species from eight genera. In total, 21 species from the eight genera were positive for Wolbachia. Significant diversity was observed among Wolbachia strains from the crickets based on five multilocus sequence typing (MLST) genes, with 15 different sequence types (STs), of which 12 STs were new to the MLST database. Five species were infected with Wolbachia of supergroup A, 11 species were infected with Wolbachia of supergroup B, and seven species were infected with Wolbachia of supergroup F. Some of the same host species harbored distinctly different Wolbachia strains, suggesting multiple infections of crickets by Wolbachia. Different cricket hosts also harbored closely related Wolbachia strains, and there were three gene recombinations. Horizontal transmission and gene recombination may allow crickets to acquire new Wolbachia strains and have increased the genetic diversity of Wolbachia.

The glucose–methanol–choline (GMC) oxidoreductase superfamily constitutes a crucial group of enzymes involved in diverse physiological processes in insects. However, a systematic investigation of this gene family in the rice leaf roller, Cnaphalocrocis medinalis—a major migratory rice pest—remains lacking. This study identified 54 CmGMC genes in C. medinalis. Genomic analysis revealed its uneven chromosomal distribution, with a conserved 12-gene tandem cluster on chromosome 23. Phylogenetic analysis classified the CmGMC genes into distinct clades, clarifying their evolutionary relationships with GMC homologs in other species. Furthermore, spatiotemporal expression profiling revealed expression of 36 CmGMC genes across all developmental stages and tissues examined, indicating the high transcriptional activity of GMC oxidoreductase genes in C. medinalis. To investigate their role in insecticide response, we examined changes in CmGMC expression following spinetoram treatment. At 48 h post treatment, 20 and 8 genes were significantly upregulated and downregulated, respectively, indicating that specific GMC oxidoreductases may play crucial roles in the molecular response of C. medinalis to spinetoram. This study provides a foundation for understanding the biological functions of GMC oxidoreductases in C. medinalis and reveals their response to the insecticide spinetoram.