Molecular genetic study of geographic forms of ladybird beetles Adalia bipunctata and A. frigida

Background: European ladybird Adalia bipunctata has forms with red and black color of the elytra. On the red elytra usually there are two round black spots, on the black - 2-4-6 red spots. A. b. turanica, A. b. revelierei, A. b. fasciatopunctata and A. frigida differ from the European A. b. bipunctata form by many spots on red or pink elytra. The taxonomic status of these forms is unclear. Materials and methods: We studied DNA diversity of the COI gene of mtDNA with C1-j-1951 и C1-N-2618 primers (Schulenburg et al., 2002) and ITS2 sequences of rRNA with 5,8S and 28S primers (Proft et al., 1999). The analysis of nucleotide polymorphism from aligned DNA sequences of both COI and ITS2 data was done using the MEGA4 software (Tamura et. al. 2007). Results: 20 variable mtDNA haplotypes in the COI gene were found among A. b. bipunctata, A. b. fasciatopunctata, A. b. revelierei and A. b. turanica, but none of them was unique to any form. All studied specimens of A. b. bipunctata, A. b. fasciatopunctata, A. b. revelierei and A. b. turanica, regardless of mitochondrial haplotype, had almost identical sequences of ITS2. Divergence recorded between species A. bipunctata and A. frigida is 1.8% in ITS2 and 4.3 % in COI. Conclusion: A. b. revelierei, A. b. turanica and A. b. fasciatopunctata are geographical variety (or subspecies) of A. bipunctata. Based on the differences in the DNA structure, we suggest that Adalia bipunctata and Adalia frigida are close but distinct indepentent species.

Adalia, polymorphism of populations, mitochondrial DNA, nuclear DNA, adaptation