Fig. 2

Structure of the sequenced mitochondrial genomes. (a) Normalized read coverage over the 15 mitochondrial genes. The genomic position of each gene is shown in the x-axis and the normalized coverage in the y-axis. The average coverage values are depicted by black lines with gaps; (b) count of reference genomes presenting different genome sizes in the RefSeq database (red) and in this study (blue). The mean genome size for each database is depicted by dashed lines. (c) Number of species containing each of the eight start codons (d) and six stop codons for the 13 protein coding gene