The mitochondrial genome of a flat bug, Brachyrhynchus hsiaoi (Blöte), is a typical circular DNA molecule of 15,250 bp with 37 genes and 70.4% A + T content. The gene order is different from that of the putative ancestral arrangement of insects with a tRNA gene rearrangement, trnQ-trnI. This rearrangement has been found in other sequenced flat bugs and is likely synapomorphic for the Aradidae or some subgroup within this family. Ten protein-coding genes start with ATN codon and others use TTG. All the 22 tRNAs, ranging from 61 to 70 bp, have the clover-leaf structure except for the dihydrouridine (DHU) arm of trnS1 forms a simple loop. The sizes of the large and small ribosomal RNA genes are 1245 and 808 bp, respectively. The control region is located between rrnS and trnQ with 703 bp in length and 69.8% A + T content.
Keywords: Aradidae; Hemiptera; flat bug; mitochondrial genome.