Mitochondrial Genomes of Two Asexual (Hymenoptera: Trichogrammatidae) Strains and Comparison with Their Sexual Relatives.

Despite its substantial costs, sexual reproduction dominates in animals. One popular explanation for the paradox of sex is that asexual reproduction is more likely to accumulate deleterious mutations than sexual reproduction. To test this hypothesis, we compared the mitogenomes of two asexual wasp strains, and to their sexual relatives. These two asexual strains represent two different transition mechanisms in from sexual to asexual reproduction. Asexual is induced by , while presumably originated from interspecific hybridization. We sequenced and assembled complete mitochondrial genomes of asexual and . Compared to four sexual relatives, we found no evidence of higher mutation accumulation in asexual mitogenomes than in their sexual relatives. We also did not detect any relaxed selection in asexual mitogenomes. In contrast, the intensified selection was detected in Nad1 and Nad4 of the asexual mitogenome, suggesting more purifying selection. In summary, no higher mitochondrial mutation accumulation was detected in these two asexual strains. This study provides a basis for further investigating mitochondrial evolution and asexual reproduction in .