Variation of nucleolar organizer regions in two 2n=48 chromosomal forms of nannospalax nehringi (Satunin, 1898) (Rodentia: Spalacidae) from North-eastern Anatolia

We describe the Ag-NOR distribution in two 2n=48 populations of blind mole rats of the genus Nannospalax from two localities (Çaldıran and Aşağısutaşlı) in the Van and Iğdır Provinces in North-eastern Anatolia, Turkey. The karyotypes of the studied populations differed in the proportion of biarmed and acrocentric autosomes (NFa=64 and 68, respectively). The nucleolar organizer regions (NORs) occurred on four autosomal pairs in the Van population whereas only three NOR-bearing autosomal pairs were detected in the Iğdır population. The karyotype of the individuals from the Iğdır population was similar to the previously studied population from the Van-Erciş Province. This similarity indicated that geographical barriers did not limit dispersal of the cytotype with NFa=68 chromosomal form in North-eastern Anatolia.