Mitochondrial Genome Features and Phylogenetic Analyses of Four Chrysochroinae Species (Coleoptera: Buprestidae)

The number of known mitochondrial genomes in Buprestidae is limited, especially in Chrysochroinae, which seriously hinders the phylogenetic study of this family. The mitogenomes of Capnodis miliaris, Lamprodila cupreosplendens, Sphenoptera insidiosa and Philocteanus rubroaureus were sequenced, assembled and annotated in this study. The mitogenomes of these four species are typical circular double-stranded DNA molecules, containing 13 protein-coding genes (PCGS), 22 transfer RNA genes (tRNAs), 2 ribosomal RNA genes (rRNAs), and a control region (CR). The total lengths of these four mitogenomes are moderate, ranging from 15,778 bp to 16,230 bp. Additionally, their A + T content ranges from 68.76% to 73.47%, showing positive AT-skew values ranging from 0.098 to 0.181. Relative Synonymous Codon Usage (RSCU) analysis indicated that TTT (Phe), ATT (Ile), TCT (Ser2), and TTA (Leu2) are the most frequently used codons. The gene arrangement of four mitogenomes is consistent with the previously reported Buprestidae mitogenomes. Most of the PCGs use ATN as the start codon, with TAA as the stop codon or an incomplete stop codon T-. Phylogenetic trees were constructed based on the PCGs and rRNAs using both maximum-likelihood and Bayesian inference methods. The phylogenetic results showed that Julodinae, Polycestinae, Buprestinae and Agrilinae are monophyletic groups, and Chrysochroinae is a paraphyletic group. As the number of Buprestidae mitogenomes used for polyogenetic analysis increases, the topology of phylogenetic tree shows differences compared to previous studies.