Exploring the mitogenomics of Triozidae (Hemiptera: Psylloidea): comparative analysis and phylogenomics

The family Triozidae (Hemiptera: Psylloidea) comprises a diverse group of plant-feeding insects. Despite the ecological significance of this family, their mitochondrial genomic resources remain scarce and phylogenetic relationships remain incompletely resolved. Here, we present the first complete mitogenome of Bactericera gobica . By integrating this newly sequenced genome with nearly all available Triozidae mitogenomes, we establish the most comprehensive dataset to date for the family. This expanded resource enables robust comparative analyses to elucidate mitogenomic evolution, clarify generic phylogenetic status, and reconstruct the divergence history of Triozidae. The B. gobica mitogenome is 14,865 bp in length, containing the standard set of 37 genes with a typical insect gene arrangement and a strong AT bias (72.1%). Comparative analysis across Triozidae revealed high conservation in gene order and protein-coding gene (PCG) lengths, while genome size variation was primarily attributed to the hypervariable control region. Codon usage bias was significantly correlated with nucleotide composition, indicating that mutational pressure is the primary driver of codon preference. Phylogenetic analyses based on 13 PCGs and 2 rRNA genes strongly supported the monophyly of Triozidae and the genera Bactericera , Egeirotrioza , and Pariaconus . However, the genus Trioza was recovered as polyphyletic, distributed across multiple distinct clades. Divergence time estimation suggested that Triozidae originated in the later Paleogene, with major diversification occurring during the early to mid-Miocene. This study provides comprehensive insights into the mitochondrial genomic architecture and evolutionary history of Triozidae. The confirmed polyphyly of Trioza highlights the urgent need for taxonomic revision within the family. These findings establish a robust molecular framework for future systematic studies and contribute to a deeper understanding of psyllid evolution.