The characterization of the mitochondrial genome of Graptemys ouachitensis

Graptemys ouachitensis (CAGLE, 1953) belongs to the Graptemys genus, the Emydidae family, and the Testudines order. This study involved sequencing the complete mitochondrial genome (mitogenome) of G. ouachitensis using next-generation sequencing, and analyzing the essential characteristics, and phylogenetic relationship. The results revealed that the G. ouachitensis mitogenome was 16,674 bp in length (A: 34.1%, C: 26.0%, G: 13.0%, T: 26.9%) and included 22 tRNAs, 13 protein-coding genes, two ribosomal RNA genes, and a non-coding control region (GenBank accession: NC071766). The genome composition of G. ouachitensis presented a slight A + T bias (61.0%) and exhibited a positive AT skew (0.118) and a negative GC skew (-0.333). A phylogenetic analysis based on the complete mitogenome indicated that the G. ouachitensis was more closely associated with Malaclemys terrapin than the other eight known Emydidae species. Thus, our findings present a novel mitogenome at the species level. This study introduces the first complete mitogenome of G. ouachitensis, providing valuable molecular information for phylogenetic and conservation genetics analyses of G. ouachitensis.