This study presents a survey of the Orchidaceae from Serra Negra and Serra do Funil (SN/SF), 'Zona da Mata', Minas Gerais state, and analyzes the floristic similarity of this family among 29 grassland and forest sites in Brazil. Cluster analysis used the UPGMA algorithm, SØrensen coefficient, and bootstrap analyses with 5,000 replications. The cluster analyses revealed low similarity indices; exceptions are the clusters composed of Serra Negra + Ibitipoca State Park and Ilha do Cardoso State Park + Juréia-Itatins Ecological Station. The results suggest that SN/SF represents a floristic corridor between sites in Serra da Mantiqueira (Itatiaia National Park) and Serra do Mar (Macaé de Cima Biological Reserve). Groups of areas with similar environmental conditions were observed and the "campos rupestres" regions stood out because of their singular floristic composition. The Mantel test revealed that floristic similarity is not associated with geographic distance between the areas.
Biodiversity; campos rupestres; conservation; Mantel test; species richness
