Comparative Cytogenetics. 2008. 2(1): 1-6.
Cytogenetic recognition of the common wood mouse, Sylvaemus sylvaticus s. l. (Mammalia: Rodentia: Muridae), in European Russia
Abstract. A male mouse singled out from the sample of 10 wood mice trapped in Kursk Province (Central European Russia) has been studied by means of karyological analysis. This mouse was allotted by a presence of distinguished chest spot of outstretched shape. There was another one specimen with the distinct chest spot of the same shape, while all the rest born very small and hardly discerned chest spot or didnít bear it at all. The diploid number and general chromosomes morphology of this individual (2n=48, all are acrocentrics) are common to all representatives of the genus Sylvaemus Ognev, 1924. Prominent block of constitutive heterochroma-tin is concentrated mainly in telomeric regions of several small and medium-sized autosomes. The centromeric heterochromatin is observed only in the largest auto-some No.1 and X-chromosome. Y-chromosome is entirely heterochromatic small acrocentric. The nucleolar organizers (AgNOR-staining) are distributed in cen-tromeric or telomeric regions of several autosomes. The wood mice with similar karyotype peculiarities were already reported from the spacious European territory between Austria in the west, Bulgaria in the south-east and Ukraine and the neigh-boring Russian region (Bryansk Prov.) in the east. New data proved that Kursk Prov. Is the second of known regions where the supposed superspecies Sylvaemus sylvaticus (Linnaeus, 1758) (Orlov et al., 1996) occurs in European Russia. At the moment it is the easternmost point of the S. sylvaticus s. l. distributional range.