Inferred structures of the mitochondrial tRNAs in both Demodex species. Structures are arranged in alphabetical order. Each tRNA gene is named according to the one-letter amino acid abbreviation, except that L1 = CUN; L2 = UUR; S1 = AGN; and S2 = UCN. A solid line indicates a Watson-Crick bond, whereas a circle indicates a bond between G and uracil. All 22 of these tRNA genes were located in the same relative position and orientation within the mitochondrial genomes of both Demodex species. Furthermore, orthologous tRNA structures all looked similar between Demodex species; to see this, compare each tRNA in panel (a) versus panel (b). Most of the tRNA molecules lacked at least one of the side arms, and some lacked both, suggesting that Demodex must have the molecular machinery necessary for these extremely truncated tRNAs to function.