Banded Karyotype Features of the Bitlis Chromosome Race (2n=54) of Nannospalax xanthodon (Nordmann, 1840) (Rodentia: Spalacidae) in Tfirkiye

Nannospalax xanthodon has five chromosome races of 2n=54 in Tiirkiye. Until now, only C-banding and Ag-NOR staining analyses of Knikkale specimens of Yozgat chromosome race have been performed. In this study, we presented the karyotype characteristics of the Bitlis chromosome race with C-banding and Ag-NOR staining analyses. The numbers of bi-armed chromosomes in set of this race were found to be nine pairs and the numbers of acrocentric chromosomes were 16 pairs. This result is compatible with data on the previously studied Tatvan specimen. However, the Y chromosome of our specimens is different from that of the Tatvan specimen of this race. The Y chromosome is medium-sized subtelocentric (NFa=70). The dark centromeric C-bands were observed in all bi-armed and some acrocentric autosomes. The X chromosome had a centromeric band, while the Y chromosome was stained C-negative. The active NORs were determined in the telomeric regions of the short arms of two autosomes. The distribution pattern of the centromeric positive C-bands was generally similar between the Bitlis and Yozgat races. However, there were no C-heterochromatic short arms in the Bitlis race. The number and position of active NORs in both races were different.