Small Mammals from Serra do Brigadeiro State Park, Minas Gerais, Southeastern Brazil: Species Composition and Elevational Distribution

Resumen

The Serra do Brigadeiro State Park represents one of the few remnants of Atlantic forest in a mountainous region of the State of Minas Gerais. The terrestrial small mammal fauna of the park within a 1200- 1800m altitudinal interval was inventoried from 1996 to 2004 to generate estimates about taxonomic composition, richness, abundance, and altitudinal distribution of species. Cytogenetic analyses were carried out for selected species as an additional tool for taxonomic identifications and diversity estimates. A sampling effort of 4620 trapping-nights resulted in 21 species of rodents (families Cricetidae and Echimyidae) and marsupials (family Didelphidae) recorded, of which seven have their karyotypes described. Cumulative curves and non-parametric estimators suggest that the overall inventory is 81% complete and that at least five species are likely to be recorded with additional sampling. Species composition and diversity varied significantly across elevational belts with the lower altitudes characterized by both forest restricted and habitat-generalist species, while the upper altitudes are exclusively characterized by elevationally widespread and habitat-generalist species. Species diversity peaked at middle elevations (1300-1400m) and the putative factors responsible for this pattern are discussed.