Complete mitochondrial genomes of Epeorus carinatus and E. dayongensis (Ephemeroptera: Heptageniidae): Genomic comparison and phylogenetic inference.

The current research on Ephemeroptera is mainly based on its morphology, since only small numbers of mitogenomes have been reported. In this study, the mitogenomes of Epeorus carinatus (15,338 bp) and E. dayongensis (15,609 bp) were sequenced, annotated and compared to genome data from congeners. Both mitogenomes had 23 tRNA genes including standard 22 and one extra tRNA. The duplicated tRNA gene had been found in other heptageniid species except Paegniodes cupulatus, suggesting it could be used as a molecular synapomorphy for partial Heptageniidae. The phylogenetic analyses based on Bayesian Inference (BI) and Maximum Likelihood (ML) showed that Heptageniidae was monophyletic and the relationships among known Epeorus species were ((E. carinatus + E. herklotsi) + (E. dayongensis + E. sp. 1)), which implied the focal species E. carinatus and E. dayongensis should be grouped into different subgenera.