Figure 2

Schematic illustration of mitochondrial genome capture and fixation of mixed cytonuclear genome in the case of the European Corbicula lineages forms R and S (Hedtke and Hillis, 2011; Pigneur et al., 2011b). The ploidy of forms R and S is still uncertain (2n or 3n), but the general mechanism of mitochondrial capture remains the same in the different cases. Here, the egg is considered diploid (unreduced) as it is in metaphase I 15 min after spawning and the reductional division has not occurred yet.