2 JAPANESE WILDCATS, THE TSUSHIMA CAT AND THE IRIOMOTE CAT, SHOW THE SAME MITOCHONDRIAL-DNA LINEAGE AS THE LEOPARD CAT FELIS-BENGALENSIS

We previously revealed, based on mitochondrial DNA sequence analysis, that the Iriomote cat is very closely related to the leopard cat Felis bengalensis, which is widespread in Asia [24]. In this study, in orde r to understand the phylogenetic status of the Tsushima cat which is t he other wildcat in Japan, partial sequences (402 bases) of the mitoch ondrial cytochrome b region were determined and compared with those of the Iriomote cat and other feline species. The phylogenetic tree of t he cytochrome b sequences indicated that the Tsushima cat and the Irio mote cat have the same mitochondrial DNA lineage as the leopard cat. O ne or two transitional substitutions were observed among the two Japan ese wildcats and the leopard cat. The divergence time (approximately 1 00,000 years ago) of the Tsushima cat and the leopard cat, estimated b y sequence data, was in concordance with the formation date of the Tsu shima Island. These results suggest that genetic drift after geographi c isolation has brought fixation of some genetic and morphological cha racters to the Tsushima cat and the Iriomote cat, while these two Japa nese wildcats are still genetically close to the continental leopard c at. Considering morphological differences and molecular phylogeny, it is reasonable for the two Japanese wildcats to be classified as two su bspecies of F. bengalensis.