The karyotype of the Azumi shrew<Emphasis Type="Italic">Sorex hosonoi</Emphasis>

Karyotype ofSorex hosonoi Imaizumi, 1954 from Mt. Asama in central Honshu, Japan, were examined with conventional staining and G-banding using ASG methods. The diploid and fundamental autosomal arm numbers were 42 and 66, respectively. The autosomes consisted of seven metacentric, six submetacentric, and seven acrocentric pairs. The sex chromosomes were large-sized acrocentric X and small-sized subtelocentric Y. The relationship between the karyotypes ofS. hosonoi andS. shinto was explained by one pericentric inversion at the no. 5 ofS. hosonoi and the no. 9 ofS. shinto. A rearrangement inS. shinto-hosonoi differed from the rearrangements occurring on no. 5 ofS. shinto-caecutiens/unguiculatus.