Melastomataceae do Planalto Diamantina, Minas Gerais, Brasil

Abstract

The Diamantina Plateau, located in the Espinhaço Range central southern region, is situated between the north of Serra do Cipó and south of Grão Mogol. The vegetation cover is composed by a mosaic of physiognomies with a predominance of campo rupestre, with a high degree of endemic species, in particular Melastomataceae. The present study aimed to estimate the diversity of Melastomataceae in the Diamantina Plateau, as well as the occurrence of species in the different phytophysiognomies, the predominant habit, the conservation and threat state, to analyze possible diversity centers for the genera, besides verifying the spatial distribution of the sampling effort in order to direct future colect and research efforts identify poorly sampled regions. We used an online database available on the speciesLink and Herbarium Virtual Reflora platforms, with filtered records for the 14 municipalities that compose the Diamantina Plateau. A total of 179 species in 23 genera were cataloged, and Miconia and Microlicia are the most representative genera (48 and 43 spp., respectively), followed by Lavoisiera (22 spp.), Pleroma (20 spp.), Cambessedesia and Fritzschia (7 spp. each), Siphanthera (5 spp.), Chaetogastra (4 spp.), Pterolepis and Trembleya (3 spp. each), Clidemia, Leandra, Marcetia and Rhynchanthera (two spp. each), Acisanthera, Chaetostoma, Desmoscelis, Huberia, Lithobium, Macairea, Merianthera, Mouriri and Ossaea (one spp. each). Among the inventoried species, 83 are endemic from Minas Gerais, with 25 species restricted to the Diamantina Plateau. The grassland had the largest number of species, mainly the campo rupestre (149 spp.). Concerning the conservation status, seven species are defined as “Critically Endangered” (CR), five species as “Near Threatened”, 35 species as “Endangered” (EN) and 14 species as “Vulnerable” (VU). Based on the analysis of the sampling effort, the Melastomataceae collections in the Diamantina Plateau are concentrated in areas close to the municipal headquarters, research centers and access roads, such as trails and roads. The largest number of collections is found in Diamantina, Biribiri State Park and Rio Preto State Park. The continuity of floristic surveys is an important aid in valuation the region's biodiversity, making it possible to preserve the flora through the creation of new conservation units.