Extrafloral nectaries of an Atlantic Forest conservation area in Southeastern Brazil

Abstract

Although extrafloral nectaries (EFNs) are reported as extremely important to understand ecological interactions, the diversity of EFN-bearing plants remains underappreciated. In Brazil, studies are concentrated in Cerrado and extremely poorly known in other phytogeographic domains, such as Atlantic forest. Thus, this study provides one of the first checklists of angiosperms with EFNs in a protected area of the Brazilian Atlantic forest, bringing information about the richness, location of EFNs on the plant's organs, as well as plant's habit and conservation status. A total of 93 EFN-bearing species belonging to 61 genera and 29 families is reported, which corresponds to 16.5 % of the local flora. The vast majority has not been evaluated for their conservation status, and twenty species are endemic to the Brazilian Atlantic forest. Vines and trees are the predominant plant habits and EFNs are mostly found on leaves. More than half of the species (53.7 %) comprises new additions to the world list of EFN-bearing plants, including the first record in Dilleniaceae. Our findings show a large number of EFN-bearing plant species from a single and small protected area in the Brazilian Atlantic forest. It reinforces the lack of studies of this nature, where further investigations are strongly recommended.