Complete Mitochondrial Genome Characterization of Schrankia costaestrigalis (Insecta: Erebidae: Hypenodinae) and Its Phylogenetic Implication

The pinion-streaked snout Schrankia costaestrigalis is a new potato pest that has recently been recorded in China. In this study, we analyzed the complete mitochondrial genome of S. costaestrigalis. The results revealed the mitogenome (GenBank: OQ181231) to occur as a circular DNA molecule of 16,376 bp with 51.001% AT content, including 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes, and 1 control region. Notably, the PCGs exhibited typical ATN (Met) start codons, including cox1, which deviated from the usual CGA start codon observed in other lepidopteran mitogenomes, and followed the conventional TAN stop codons. The 22 tRNA genes demonstrated the ability to form a cloverleaf structure, with the exception of trnS1-NCU, which lacked the DHU arm present in other Erebidae mitogenomes. Additionally, conserved motifs like ATAGA + poly-T (19 bp) stretch and five microsatellite-like elements (TA) were identified in the AT-rich region. The phylogenetic trees revealed that the Hypenodinae subfamily forms an independent lineage closely related to Erebinae and Catocalinae. The comprehensive mitogenome of S. costaestrigalis will greatly enhance future studies focused on the molecular classification and phylogenetic understanding of the Hypenodinae subfamily within the larger family Erebidae.

Automated summary

This study analyzed the complete mitochondrial genome of the pinion-streaked snout Schrankia costaestrigalis and found unique features, such as deviations in the start and stop codons of protein-coding genes, structural changes in tRNA genes, and conserved motifs in the AT-rich region. Phylogenetic analysis revealed a close relationship between S. costaestrigalis, the Hypenodinae subfamily, and the Erebinae and Catocalinae subfamilies.