Fig. 3

Relative synonymous codon usage (RSCU) in the mitochondrial genomes of (A) P. rubripinnis and (B) I. japonicus. The x-axis shows the 20 amino acids and their corresponding codons. The y-axis represents the RSCU values, with values greater than 1 indicating codons used more frequently than expected. The specific codons are listed below each amino acid in both (A) and (B). The color of each bar indicates particular codons.