Geographic variation and molecular evidence of the Blackish Deer Mouse complex (Peromyscus furvus, Rodentia: Muridae)

Several authors have discussed whether Peromyscus furvus is a monotypic species rather than a polytypic entity, that it includes more than one species. Here, we analyze these questions by means of traditional morphometrics and by genetic analyses using ND3-ND4 mtDNA genes as markers. In spite of a generalized overlap of the measurable characters among populations, our analyses show that the northernmost populations, which was assignable to P. latirostris, consistently show larger dimensions overall. The amount of genetic differentiation revealed by our molecular data, support conclusive evidence to suggest this taxon is a valid species. Our results also disclose that morphometric and molecular segregation between P. furvus and P. angustirostris is still incomplete. Finally, the two populations from the state of Oaxaca showed more morphometric affinity with those attributable to P. furvus and revealed a discrete degree of genetic differentiation. Nevertheless, their systematic position is not clear yet.