The complete mitochondrial genome of Lithobates catesbeianus (Anura: Ranidae) is sequenced to analyze the gene arrangement. It is a circular molecule of 18,241 bp in length including 37 genes typically found in other frogs. The AT content of the overall base composition of L. catesbeianus is 59.9%. The length of control region is 2783 bp with 66.0% AT content. Protein-coding genes begin with ATG as start codon except except ND1 and ATP6 began with ATA, COI and ND4L with GTG, and ND2 with ATT. COI end with AGG as stop codon, COII and ND6 end with AGA, ND2 end with TAG, ATP8. ND4L. ND5 and Cytb end with TAA, and the other five PCGs end with a incomplete stop codon (a single stop nucleotide T).

The complete mitochondrial genomes of the yellow-bellied slider (Trachemys scripta scripta) and anoxia tolerant red-eared slider (Trachemys scripta elegans) turtles were sequenced to analyze gene arrangement. The complete mt genomes of T. s. scripta and elegans were circular molecules of 16,791 bp and 16,810 bp in length, respectively, and included an A + 1 frameshift insertion in ND3 and ND4L genes. The AT content of the overall base composition of scripta and elegans was 61.2%. Nucleotide sequence divergence of the mt-genome (p distance) between scripta and elegans was 0.4%. A detailed comparison between the mitochondrial genomes of the two subspecies is shown.

The complete mitochondrial genome of Mauremys sinensis (Testudines: Geoemydidae) is sequenced in the study. It is a circular molecule of 16,458 bp in length, consisting of 37 genes typically found in other turtles. The AT content of the overall base composition of M. sinensis is 60.2%. The length of control region is 928 bp with 66.1% AT content. An insertion of additional adenine base was observed in location of 175th base of ND3 gene. Protein-coding genes begin with ATG as start codon except COI with GTG. ATP6, ATP8, COII, ND4, ND4L, and ND5 genes end with TAA as stop codon; ND1, ND2, and ND3 end with TAG; COI end with AGG; ND6 end with AGA; and COIII and Cyt b end with an incomplete stop codon (a single stop nucleotide T).