Study on the mitochondrial genome and phylogeny of Rhinogobius changtinensis

Objective The genus Rhinogobius is highly diverse in species, and exhibits significant variation in morphological traits, makeing traditional morphological methos unreliable for accurate species identification and classification. Rhinogobius changtinensis, a species in this genus, lacks clear mitochondrial genomic data, and its phylogenetic relationships remain poorly understood. This study aims to analyze the mitochondrial genome of R. changtinensis and provide insights into species identification, classification, and the phylogenetic study of the genus Rhinogobius.

Methods Using the Illumina NovaSeq X Plus platform, the study conducted next-generation sequencing on the mitochondrial genome of R. changtinensis, followed by the assembly and annotation of the genome sequence, and then analyzed the structural features and base composition of the mitochondrial genome. Based on the nucleotide sequences of 13 protein-coding genes, the study constructed a phylogenetic tree using maximum likelihood (ML) and Bayesian inference (BI) methods.

Results The mitochondrial genome of R. changtinensis was 16 487 bp in length, comprising 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and an A+T-rich region of 854 bp. The gene arrangement was consistent with most species within the genus. Phylogenetic analysis indicated that R. changtinensis was the most closely related to Rhinogobius duospilus (PP=1, BS=100%).

Significance This study provides valuable mitochondrial genomic data for R. changtinensis and offers crucial insights into the phylogenetic relationships within the genus Rhinogobius, contributing to the understanding of its systematics.