Complete Mitochondrial Genome of Eurostus validus (Hemiptera: Tessaratomidae): Genomic Features and Comparative Analysis
TL;DR
The first complete mitogenome of Eurostus validus is reported and indicates that both mutation pressure and natural selection shape codon usage bias, with natural selection playing a dominant role.
Abstract
The genus Eurostus is distributed across East and Southeast Asia, inhabiting forest and agricultural ecosystems and participating in plant-insect interactions. However, the absence of a complete mitochondrial genome has limited understanding of its evolution and phylogeny. Here, we report the first complete mitogenome of Eurostus validus. The circular genome is 15,948 bp and contains the typical 37 genes, including 13 protein-coding genes (PCGs), 22 transfer RNAs, two ribosomal RNAs, and a control region. Comparative analyses with other tessaratomid mitogenomes revealed strong AT bias, consistent strand asymmetry, and conserved patterns of amino acid and codon usage. Among Pentatomoidea, atp8 showed the highest nucleotide diversity, whereas cox1 was the most conserved. ENC-plot and neutrality analyses indicated that both mutation pressure and natural selection shape codon usage bias, with natural selection playing a dominant role. Phylogenetic analyses based on the PCG12RNA dataset using Bayesian inference and maximum likelihood strongly supported family monophyly. The topology recovered Dinidoridae and Tessaratomidae as sister groups, with well-resolved relationships within Tessaratomidae. These results provide a valuable genomic resource and improve understanding of Pentatomoidea evolution.