Diversity of the Passiflora L. in the Serra do Mar ecoregion and the relationships with environmental gradients, South and Southeast, Brazil

The species of the Passiflora (Passifloraceae s.s. ) are distributed in tropical and subtropical regions and are of great ecological importance. The Serra do Mar is formed of large escarpments along Brazil’s east coast, between the States of Rio de Janeiro and Rio Grande do Sul. This study aims to point out occurrences of Passiflora species in herbaria along the Serra do Mar, in addition to evaluating the conditions of each specimen found. The richness and sample effort maps were prepared to establish the locations where the greatest numbers of species and records were encountered. We evaluated the relationship of species distribution through Canonical Correlation (CCA) and Quadratic Polynomial Analysis. We also evaluated the floristic composition using a cluster analysis. Calculations of the Extent of Occurrence (EOO) and Area of Occupancy (AOO) were performed for endemic species to the Atlantic Forest area occurring in the Serra do Mar. A total of 53 species, belonging to the Passiflora were found in the Serra do Mar. The States of Rio de Janeiro and São Paulo were the ones that recorded the greatest numbers of species and collection effort. The climatic variables Precipitation of the Driest Quarter and Annual Average Temperature are the most correlated to the distribution of Passiflora in the area. Twenty-two species are endemic to the Atlantic Forest area, and 21 are recorded as having some degree of threat on Official Lists. In this study, we present all the Passiflora species recorded for the Serra do Mar, the richness of species, including those endemics to the Atlantic Forest, demonstrates the importance of the area for conservation.