The mitochondrial genome sequence of <i>Tropilaelaps mercedesae</i> from China (Acari: Laelapidae): genome characterization and phylogenetic analysis

Mitochondrial genome sequences serve as reliable molecular markers and play a crucial role in species evolutionary analysis. From adult specimens of <i>Tropilaelaps mercedesae</i>, we successfully extracted the mitochondrial genome, obtaining a sequence of 15,009 base pairs (bp). This mitochondrial genome comprises 13 protein-coding genes (PCGs), two ribosomal RNA genes, 22 transfer RNA genes (tRNAs), and one control region. Research on codon usage bias in protein-coding genes reveals that most amino acids favour codons ending in A/U, with the codon usage pattern being predominantly shaped by mutational pressure, potentially supplemented by the effects of natural selection. Compared to other species within Dermanyssoidea, the mitochondrial genome of <i>T. mercedesae</i> displays a novel arrangement pattern. To explore the phylogenetic position of Dermanyssoidea, we utilized 13 protein-coding genes and applied maximum likelihood and Bayesian inference methods. The analysis revealed that <i>T. mercedesae</i> forms an independent branch and shares a closer relationship with Rhinonyssidae. Our findings constitute the first complete mitochondrial genome of the genus <i>Tropilaelaps</i>, laying the groundwork for future investigations into mitochondrial gene rearrangements and phylogenetics within Dermanyssoidea.