Anuran assemblage changes along small-scale phytophysiognomies in natural Brazilian grasslands

We studied the species composition of frogs in two phytophysiognomies (grassland and forest) of a Ramsar site in southern Brazil. We aimed to assess the distribution of species on a small spatial scale and dissimilarities in community composition between grassland and forest habitats. The sampling of individuals was carried out through pitfall traps and active search in the areas around the traps. We evaluated the existence of these differences by using permutational multivariate analysis of variance and multivariate dispersion. We found 13 species belonging to six families. Leptodactylidae and Hylidae were the most representative families. The compositional dissimilarity was higher between the sampling sites from different phytophysiognomies than within the same phytophysiognomy, suggesting that forest and grassland drive anuran species composition differently. Also, the difference in anuran species composition between the sampling sites within the forest was considerably high. Based on our results, we could assume that the phytophysiognomies evaluated here offer quite different colonization opportunities for anurans, especially those related to microhabitat characteristics, such as microclimate variables.