Mt genomic features of Platysternon. Typical arrangement of vertebrate mitochondrial genes including a single control region compared to that of Platysternon. All genes are transcribed from left to right except where indicated by arrows. The genes that are rearranged in Platysternon are indicated in bold while the duplicated control regions are designated by numerals (cr1, cr2). The grey boxes in the Platysternon genome represent non-coding regions (perhaps degraded duplicated copies of genes) that are not present in typical vertebrate mt genomes. This figure illustrates how sequences from two non-adjacent regions were inserted between trnI and trnQ.