Abstract
Rodents constitute 40% of mammals inhabiting earth and are found in all continents except Antarctica. The phylogeny of rodents is obscure and there is a lack of resolution owing to unavailability of morphological and genetic data. This study concerns the phylogeny of a road-kill rodent discovered from the Melghat Tiger Reserve (MTR) in Amravati, Central India. Due to small sample size, limited morphological data was generated and compared with other members of the genus using photographs. Using a tiny bit of preserved tissue, we successfully amplified and sequenced one nuclear IRBP and a mitochondrial Cyt b gene in this rodent. Nuclear and mitochondrial gene Bayesian Inferred (BI) phylogenetic trees revealed it to be a murid, showing genetic affinities to the genus Millardia. Interestingly, the Cyt b based phylogeny shows clustering of our new sequence with two Millardia species, M. kathleenae and M. meltada in a distinct monophyletic clade. The IRBP based BI tree revealed it to be paraphyletic with respect to the species of the Millardia genus. Genetic distance estimation for both mitochondrial and nuclear genes also exhibited significant differences with the known Millardia species. Thus, the possibility of a new species of genus Millardia, or even a new genus in the family Muridae in the unexplored region of Central India cannot be ruled out.References
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