The complete mitochondrial genome of Evania appendigaster (Hymenoptera: Evaniidae) has low A+T content and a long intergenic spacer between atp8 and atp6.

The apocritan Hymenoptera show extraordinary features in mitochondrial genomes, but no complete sequence has been reported for the basal lineage, Evanioidea. Here, we sequenced the complete mitochondrial genome of Evania appendigaster. This genome is 17,817 bp long; with low A+T content, 77.8%, compared with other hymenopteran species. Four tRNA genes were rearranged, among which remote inversion is the dominant gene rearrangement event. Gene shuffling is caused by tandem duplication-random loss while remote inversion is best explained by recombination. The start codon of nad1 was found as TTG, which might be common across Hymenoptera. trnS2 and trnK use abnormal anticodons TCT and TTT, respectively, and the D-stem pairings in trnS2 are absent. The secondary structure of two rRNA genes are predicted and compared with those in other insects. Five long intergenic spacers were present, including a long intergenic spacer between atp8 and atp6, where these two genes overlap in the previously reported animal genomes. A conserved motif was found between trnS1 and nad1, which is proposed to be associated with mtTERM. The A+T-rich region is 2,325 bp long, among the longest in insects, and contains a tandem repeat region.