The first two complete mitochondrial genomes for the family Triglidae and implications for the higher phylogeny of Scorpaeniformes

The mitochondrial genome (mitogenome) can provide useful information for analyzing phylogeny and molecular evolution. Scorpaeniformes is one of the most diverse teleostean orders and has great commercial importance. To develop mitogenome data for this important group, we determined the complete mitogenomes of two gurnards Chelidonichthys kumu and Lepidotrigla microptera of Triglidae within Scorpaeniformes for the first time. The mitogenomes are 16,495 bp long in C. kumu and 16,610 bp long in L. microptera. Both the mitogenomes contain 13 protein-coding genes (PCGs), 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes and two non-coding regions. All PCGs are initiated by ATG codons, except for the cytochrome coxidase subunit 1 (cox1) gene. All of the tRNA genes could be folded into typical cloverleaf secondary structures, with the exception of tRNA(Ser(AGN)) lacks a dihydrouracil (DHU) stem. The control regions are both 838 bp and contain several features common to Scorpaeniformes. The phylogenetic relationships of 33 fish mitogenomes using Bayesian Inference (BI) and Maximum Likelihood (ML) based on nucleotide and amino acid sequences of 13 PCGs indicated that the mitogenome sequences could be useful in resolving higher-level relationship of Scorpaeniformes. The results may provide more insight into the mitogenome evolution of teleostean species.