The Gene Rearrangement, Loss, Transfer, and Deep Intronic Variation in Mitochondrial Genomes of .

The genus s.s. was newly delimited from s.l. In order to gain insight into its mitochondrial genetic background, this study sequenced six mitochondrial genomes of the genus s.s. These mitogenomes were all composed of circular DNA molecules, ranging from 29,253 to 48,417 bp in size and from 26.61 to 27.90% in GC content. The order and direction for 14 core protein-coding genes (PCGs) were identical, except for the gene lost in , , and , and rearranged in the other s.s. species. Besides, the gene split the gene in . Phylogenomic analysis based on the 14 core PCGs confirmed that all s.s. species formed a monophyly in the lineage. The number and length of introns were the main factors contributing to mitogenomic size, and deep variations and potential transfer were detected in introns. In addition, gene transfer occurred between the mitochondrial and nuclear genomes. This study promoted the understanding of the evolution and phylogeny of the s.s. genus.