Cytogenetics of mole rats of the Spalax ehrenbergi superspecies from Jordan (Spalacidae, Rodentia)

Karyotypes (chromosome sets and the banding patterns (G-, C- and Ag-NOR) of the Spalax ehrenbergi superspecies across 12 localities from Jordan are de scribed far the first time. All more rats from this region (excluding two i ndividuals from Madaba with 2n = 62) have a diploid chromosome number of 2n = 60 but they display geographical variability in the number of autosomal arms (NFa = 68, 70, 72 and 74). The most widely distributed cytotype (from Madaba in the north to Wadi Musa, near Petra, in the south) has four pairs of small biarmed chromosomes. Karyotypes of two northern populations (Irbid and Zarqa) contain six pairs of small biarmed chromosomes. The intermediat e karyotype with five small biarmed chromosomes is found 25 km north of Mad aba, and a polymorphic population (Mt. Nebo) with five (2 animals) and four (4 animals) pairs of small biarmed chromosomes occurs between the northern and southern cytotypes. Geographical variability is also displayed by the short arm length in the first subtelocentric autosomes. All karyotypes have a similar C-banding pattern, with the exception of heterochromatin distrib ution in the variable first pair. Comparative analysis of G-banded chromoso mes indicated that NF differentiation is due to pericentric inversions or c entromere shift. Relationships between Jordanian, Israeli, and Turkish spec ies of the Spalax ehrenbergi superspecies are discussed.