Phylogenetic relationships among Asian species of Petaurista (Rodentia, Sciuridae), inferred from mitochondrial cytochrome b gene sequences

To elucidate the phylogenetic relationships among four species belonging to the genus Petaurista (P. alborufus castaneus, P. alborufus lena, P. leucog enys leucogenys, P. leucogenys nikkonis, P. petaurista melanotus, and P. ph ilippensis grandis), we investigated the partial sequences (1,068 bp) of th e mitochondrial cytochrome b gene for these giant flying squirrels. Phyloge netic trees (NJ, MP, and ML trees) constructed from cytochrome b sequences indicated that P. leucogenys was grouped independently with other species, and that P. philippensis was most closely related to P, petaurista with 99- 100% bootstrap values. In addition, two subspecies of P. alborufus did not form a single clade: P. alborufus castaneus from China was most distantly r elated to the other species, whereas P. alborufus lena from Taiwan was clos ely related to P. petaurista and P. philippensis with 82-90% bootstrap valu es. This result suggests that it is reasonable to regard P. alborufus lena as a distinct species from P. alborufus castaneus.