Enhanced Sequence Evolution Rates Correlate with Significant Rearrangements in Coccoid Mitochondrial Genomes

Scale insects, which belong to the superfamily Coccoidea within the order Hemiptera, encompass more than 8000 species worldwide. The adult females of these species are characterized by their immobility, and often lack wings and legs. Scale insects feed on plant tissues and can cause significant agricultural damage as pests. This study presents the sequencing of five coccoid mitogenomes, revealing detailed annotations and comparisons with other Hemiptera. The sequencing yielded between 73 million and over 121 million reads, allowing for the reconstruction of mitogenomes ranging from 12,821 to 14,446 nucleotides. Notably, a high A + T content was observed across the newly sequenced mitogenomes. Gene rearrangements were identified in all five newly sequenced mitogenomes, with the evolutionary rate analysis indicating that Coccoidea exhibit the highest Ka and Ka/Ks values among the hemipterans. In a phylogenetic context, the mitogenomes of representative species from Coccoidea and Aleyrodoidea exhibit more frequent mitochondrial gene rearrangements than those of other hemipteran groups. The analysis suggests that the frequent mitochondrial gene rearrangements observed in the coccoid species are associated with accelerated nucleotide substitution rates, supporting a connection between genetic evolution and structural variation in mitogenomes.