Complete Mitochondrial Genome of the Backswimmer: Notonecta triguttata Motschulsky, 1861 (Hemiptera: Notonectidae): Sequence, Structure, and Phylogenetic Analysis

Abstract

Notonecta triguttata Motschulsky, 1861 (Hemiptera, Notonectidae) is distributed in China, Japan, and South Korea. It is the dominant hexapod predator in aquatic ecosystems and can control harmful insects, such as mosquitoes and parasites. This study presents the first determination of the complete mitochondrial genome of N. triguttata. The mitogenome was 15,156 base pairs in length and was made up of 13 protein-coding genes (PCGs), 2 ribosomal RNAs, 22 transfer RNAs, and one non-coding control region. All genes were arranged in the same order as most other known heteropteran mitogenomes. All PCGs started with the ATN codon except COX1 (TTG) and NAD2 (GTG) and ended with TAA, TAG, or the partial stop codon T. The tRNAs had a typical cloverleaf secondary structure, except tRNA-Ser (GCT). The A + T content (75.96%) was relatively high across the entire mitogenome. The optimal phylogenetic trees were inferred through the Bayesian inference and maximum likelihood methods. The trees suggested a topology of (Corixoidea + ((Nepoidea + Ochteroidea) + (Naucoroidea + (Pleoidea + Notonectoidea)))) and identified that N. triguttata belongs to Notonectoidea. The complete mitogenome of N. triguttata provides a potentially useful resource for further exploration of the taxonomic status and phylogenetic history of the Notonecta species.