Chromosomal and Allozyme Characterization of the Caucasian Shrew, Sorex Satunini, from North-Eastern Turkey

Abstract

Fifteen individuals of the Caucasian shrew, Sorex satunini, from five sites in north-eastern parts of Asian Turkey were examined. All the shrews were studied by starch gel electrophoresis whereas 7 animals from 3 localities were karyotyped. The diploid number of autosomes was 2na= 22; there was one pair of large metacentrics, one pair of large submetacentrics, four pairs of medium-sized meta-/submetacentrics, four pairs of small biarmed elements, and a single pair of small acrocentrics in the diploid karyotype (NFa= 42). The sex chromosomes made up a standard XX bivalent in females and an XY1Y2 trivalent in males. Out of 36 allozyme loci scored, seven were found to be polymorphic in at least one population of S. satunini. One locus appeared to be discriminant and three other loci were partially discriminant between the Caucasian shrew and S. araneus. Indices of genetic variability, i.e., mean number of alleles per locus (A), frequency of polymorphic loci (P5%), and mean heterozygosity (Hc) displayed rather low values in all the samples of the Caucasian shrew under study. Moreover, Nei's genetic distances within the Turkish S. satunini were found to be extremely low (0.000-0.001). The electrophoretical results were then compared with previously published data from the Czech Republic, Slovenia and Macedonia at 27 loci. The genetic distances between populations of the two species appeared to range between 0.052 and 0.110.