DNA barcoding reveals twelve lineages with properties of phylogenetic and biological species within Melitaea didyma sensu lato (Lepidoptera, Nymphalidae)

The complex of butterfly taxa close to Melitaea didyma includes the traditionally recognized species M. didyma, M. didymoides and M. sutschana, the taxa that were recognized as species only relatively recently (M. latonigena, M. interrupta, M. chitralensis and M. mixta) as well as numerous described subspecies and forms with unclear taxonomic status. Here analysis of mitochondrial DNA barcodes is used to demonstrate that this complex is monophyletic group consisting of at least 12 major haplogroups strongly differentiated with respect to the gene COI. Six of these haplogroups are shown to correspond to six of the above-mentioned species (M. didymoides, M. sutschana, M. latonigena, M. interrupta, M. chitralensis and M. mixta). It is hypothesized that each of the remaining six haplogroups also represents a distinct species (M. mauretanica, M. occidentalis, M. didyma, M. neera, M. liliputana and M. turkestanica), since merging these haplogroups would result in a polyphyletic assemblage and the genetic distances between them are comparable with those found between the other six previously recognized species.