Two complete mitochondrial genomes of the subfamily Chloroperlinae (Plecoptera: Chloroperlidae) and their phylogenetic implications

Two new complete mitochondrial genomes (mitogenomes) of the subfamily Chloroperlinae, Haploperla japonica Kohno, 1946 and Sweltsa sp., were sequenced. The two species showed similar gene order, nucleotide composition, and codon usage. The Sweltsa sp. and H. japonica mitogenomes were typical circular DNA molecules, with lengths of 15,893 bp and 16,012 bp, respectively. Standard ATN start and TAN stop codons were present in most PCGs. All tRNA genes exhibited the cloverleaf secondary structure typical for metazoans except the tRNA^Ser(AGN), which lacked the dihydrouridine arm. In both species, the secondary structure of lrRNA contained five structural domains, while the srRNA included three domains. The A+T-rich regions contained different repeat regions in each species. Phylogenetic analyses using Bayesian inference (BI) and maximum likelihood methods (ML) showed identical results. The family Chloroperlidae was sister to the Perlodidae. Our analyses inferred relationships between six of the seven Systellognatha families: (((Chloroperlidae + Perlodidae) + Perlidae) + (Styloperlidae + Pteronarcyidae)) + Peltoperlidae.