Organization of the mitochondrial genome of Demodex folliculorum . Protein-coding, ribosomal RNA, and transfer RNA genes are depicted as green, blue, and red arrows, respectively. The arrows represent the direction of transcription. The AT-rich, putative control region is depicted as a gray box (labeled “D-Loop”). Inside the circle is a scanning electron micrograph of an individual D. folliculorum (image credit: Power and Syred). The identical gene arrangement was observed in the D. brevis mitochondrial genome. This is a novel gene arrangement among the acariform mitochondrial genomes sequenced to date. Like other members of the Acariformes, Demodex proved to have a compact and AT-rich mitochondrial genome.