Abstrakt: |
Abstract: Sequence data for the nuclear ITS2 region and part of the mitochondrial cytochrome b gene were used to reveal intraspecific phylogeography and population genetic structure of the oak gall wasp Trigonaspis synaspis from Anatolia. One hundred and sixty six individuals representing 21 populations yielded 50 unique cyt b haplotypes and 15 ITS2 alleles. Genetic diversity estimates indicated the existence of high molecular variation, with average gene diversities of 0.85541 and 0.3119 for cyt b and ITS2 respectively. Likewise, nucleotide diversity was 0.01346 for cyt b and 0.0015 for ITS2. Pairwise divergence ranged from 0.2 to 3.1% between cyt b haplotypes, and from 0.2 to 2.8% between ITS2 alleles. Phylogenetic analyses of the cyt b haplotypes conducted using three different approaches produced mostly similar topologies, and major clades generally grouped haplotypes with similar geographic origins. Contrary to the mtDNA results, ITS2 analyses produced largely similar but polytomous topologies lacking apparent geographic structure. Application of the widely used insect mitochondrial molecular clock linked the origin of major phylogeographic structure to the effects of the Quaternary climatic oscillations. The outgroup haplotypes of T. megaptera are inferred to have diverged from T. synaspis around the late Pliocene. Intraspecific node ages in T. synaspis link major clade structure to the Pleistocene glacial cycles. Geographical formations in Anatolia were also probably an important factor in shaping the phylogeographic structure of T. synaspis. |