The mitochondrial genome of an assassin bug, Oncocephalus breviscutum Reuter, is a typical circular DNA molecule of 15,984 bp with 37 genes and a large control region. The gene order is identical to that of the putative ancestral arrangement of insects. Twelve protein-coding genes start with ATN codon and ND4L uses GTG. All of the 22 tRNAs, ranging from 61 to 70 bp, have the clover-leaf structure except for the dihydrouridine (DHU) arm of trnS2 forms a simple loop. The control region is 1345 bp in length and includes six tandem repeats of three 31-nt and three 145-nt units.
Keywords: Assassin bug; Hemiptera; Reduviidae; mitochondrial genome.