Complete mitochondrial genome of the Chinese Callipogon (Eoxenus) relictus (Cerambycidae: Prioninae) with phylogenetic analyses.

BACKGROUND

The endangered longhorn beetle Callipogon (Eoxenus) relictus, which was designated as a natural monument since 1968 in Korea is still attracting public concern because of its extraordinary body size. Although mitochondrial genome data of this species was reported using Korean individual in 2017, start codon of cox1 is controversial and the secondary structures of transfer RNAs have not been illustrated.

OBJECTIVE

To report complete mitochondrial genome of Callipogon (Eoxenus) relictus from Chinese breed.

METHODS

We used dissected muscle tissues from an adult of Callipogon (Eoxenus) relictus. A total of 19,276,266,645 bp from 127,657,395 reads were generated. The raw reads were assembled to mitochondrial genome data and annotated. Folded structures of transfer RNAs were drawn. Phylogenetic relationships were estimated by maximum likelihood and Bayesian inference analyses.

RESULTS

The mitochondrial genome of C. relictus was 15,745 bp in length and composed of 37 genes including 13 protein-coding genes (PCGs), two ribosomal RNAs, and 22 transfer RNAs. The overall base composition was 38.40% for A, 30.98% for T, 11.06% for G, and 19.56% for C. Most transfer RNAs were folded into the typical clover-leaf structure except trnS1. Phylogenetic analyses confirmed the monophyletic status of each subfamily.

CONCLUSION

Mitochondrial genome composition was consistent with previous research, however, we suggest another start codon of cox1 gene and provide illustrated secondary structures of transfer RNAs. Phylogenetic analyses showed that subfamilies Cerambycinae and Prioninae are closely related.