Comparative Mitogenomics of Wonder Geckos (Sphaerodactylidae: Teratoscincus Strauch, 1863): Uncovering Evolutionary Insights into Protein-Coding Genes

<b>Background:</b> Comparative studies of selection pressures on mitochondrial genomes and protein-coding genes (PCGs) are scarce in the genus <i>Teratoscincus</i> (Strauch, 1863), particularly within Sphaerodactylidae. Given their close evolutionary relationship, <i>Teratoscincus przewalskii</i> (Strauch, 1887) and <i>Teratoscincus roborowskii</i> (Bedriaga, 1906) serve as ideal models for the characterization of mitochondrial genome sand analysis of selective pressure in this genus. <b>Methods:</b> In this study, we employed Sanger sequencing to sequence the mitochondrial genome of <i>T. roborowskii</i> (Bedriaga, 1906), and utilized sliding window analysis, selection pressure analysis etc. to compared it with that of its close relative, <i>T. przewalskii</i> (Strauch, 1887). <b>Results:</b> The results contain the genome composition, <i>Ka</i>/<i>Ks</i> values, AT/GC-skew, etc. Selection pressure analysis of PCGs across <i>Teratoscincus</i> (Strauch, 1863) species (including those in GenBank) revealed that most genes evolve slowly, with the exception of <i>ATP8</i> and <i>ND6</i>, which exhibited faster evolutionary rates. Notably, the <i>ND6</i> of <i>T. roborowskii</i> (Bedriaga, 1906) demonstrated rapid non-synonymous substitution rates which may contribute to the survival and reproductive success of the species by favoring advantageous mutations. Phylogenetic analysis for the mitochondrial genomes of Sphaerodactylidae, Phyllodactylidae, and Gekkonidae confirmed the distinctiveness of Sphaerodactylidae and the two <i>Teratoscincus</i> (Strauch, 1863) species. <b>Conclusions:</b> This study has advanced the understanding of adaptive evolution in <i>Teratoscincus</i> (Strauch, 1863) mitochondrial genomes, expanded the mitochondrial database of Sphaerodactylidae, and provided insights into the phylogenetic relationships of the genus.