Complete Mitogenome and Phylogenetic Analysis of a Marine Ray-Finned Fish, Alcichthys elongatus (Perciformes: Cottidae)

Alcichthys elongatus is the only species in the genus, and this work is the first to provide a comprehensive mitogenome analysis of this species. The A. elongatus mitogenome was 16,712 bp long, with biased A + T content (52.33%), and featured thirteen protein-coding genes (PCGs), twenty-two tRNAs, two rRNAs, and the control region (D-loop). The H strand encoded twenty-eight genes (twelve PCGs, fourteen tRNA, and two rRNA) and the control region, whereas the L strand encoded the remaining nine genes (ND6 and eight tRNA). Except for COXI, which started with GTG, all PCG sequences started with ATG and ended with TAA (ND4L, ND5, COXI, ATP8) or TAG (ND1, ND6) termination codons, with some (ND2, ND3, ND4, COXII, COXIII, ATP6, Cytb) having an incomplete termination codon. Except for tRNA-serine-1 (trnS), the majority of the tRNAs exhibited characteristic cloverleaf secondary structures. Based on 13 PCGs, phylogenetic analysis placed A. elongatus in the same clade as Icelus spatula. This genomic data will be useful for species identification, phylogenetic analysis, and population genetics.

Automated summary

This study provides the first comprehensive mitogenome analysis of Alcichthys elongatus, revealing its genomic features and phylogenetic placement. The mitogenome of A. elongatus is 16,712 bp long, contains thirteen protein-coding genes, twenty-two tRNAs, two rRNAs, and a control region. Phylogenetic analysis based on the protein-coding genes places A. elongatus in the same clade as Icelus spatula. These genomic data are valuable for species identification, phylogenetic analysis, and population genetics.