The complete mitochondrial genome of the Tanichthys flavianalis (Cypriniformes: Tanichthyidae) and its phylogeny.

In the present study, we have sequenced, annotated and characterized the complete mitogenome of Tanichthys flavianalis Li, Liao & Shen, 2022, which is an endemic minnow to Hainan Province, China. The entire mitogenome size is 16,545 bp, containing 37 genes coding for 13 mitochondrial proteins, 22 tRNAs, 2 rRNAs, and one putative control region. It has the typical fish mitochondrial gene arrangement, though with 9 gene overlaps and 17 intergenic spacers scattering throughout the mitogenome, and a high A + T bias (60.8%) comparing to other Cyprinids. ATG is used as the start codon in most mitochondrial protein coding genes (PCGs) except for cox1 which uses GTG, whereas the canonical TAA/TAG are prevailing stop codons except for cox2, cox3, nad4 and cytb. Phylogenetic analyses with other reported species from Tanichyidae were conducted using IQ-TREE and MrBayes, based on the concatenated 13 PCGs. The results clustered T. flavinalis with the newly described T. albiventris Li Bohlen & Liao, 2022, and proved the reciprocally monophyletic relationship between Chinese and Vietnamese Tanichthys.