Intrapopulation karyotypic and cranial characterization of Blarinomys breviceps (Rodentia: Sigmodontinae) from Minas Gerais, Brazil

Abstract Despite its wide geographical distribution and habit specialization, Blarinomys breviceps is an understudied species. In this work, we analyzed for the first time the intrapopulation variation of the karyotype and cranial measurements of specimens collected in Minas Gerais state, Brazil. We described three new karyotypes with different diploid numbers due to the presence of B chromosomes (2n = 40, 2n = 41, and 2n = 42, with FN = 50), using conventional staining, GTG- and CBG-banding, Ag-NOR, and FISH with a telomeric probe. In addition, morphometric analyses based on twenty-two quantitative cranial characters showed absence of sexual dimorphism contributing to future studies of geographic variation of the species.