Beta diversity patterns of anuran metacommunities along different vegetation types in the Atlantic Forest of southeastern Brazil

The spatial and temporal distribution of species is influenced by multiple processes operating at various scales. Beta diversity, which describes variation in species composition among sites, helps to understand community assembly mechanisms in spatial dimensions. Taxonomic beta diversity reflects differences in species composition, while functional beta diversity accounts for variations in ecological roles and traits among species. Both provide insights into the processes influencing the patterns of composition of communities. Accordingly, this study explores taxonomic and functional beta diversity patterns in anuran communities across different vegetation types in the Atlantic Forest of southeastern Brazil, focusing on two components of variation in species composition: turnover and nestedness. Field surveys were conducted in 16 sites in northern Rio de Janeiro state, covering five vegetation types. Our findings show that species turnover predominantly drives beta diversity, both taxonomically and functionally. Montane and Submontane Ombrophilous Forests contribute significantly to both taxonomic and functional beta diversity by hosting unique assemblages of species, including microendemic taxa and rare functional traits not found in other vegetation types. Nevertheless, other vegetation types also harbour exclusive species and contribute to overall diversity. Rather than focusing solely on conservation recommendations, these findings provide novel insights into how turnover and nestedness contribute differently to taxonomic and functional beta diversity, revealing the distinct ecological processes and habitat characteristics that shape anuran community composition across the Atlantic Forest.