Anurans exhibit limited dispersion ability and have physiological and behavioural characteristics that narrow their relationships with both environmental and spatial predictors. So, the relative contributions of environmental and spatial predictors in the patterns of taxonomic and functional anuran beta diversity were examined in a metacommunity of 33 ponds along the coast of south Brazil. We expected that neutral processes and, in particular, niche-based processes could have similar influence on the taxonomic and functional beta diversity patterns. Distance-based methods (db-RDA) with variation partitioning were conducted with abundance data to examine taxonomic and functional facets and components (total, turnover and nestedness) in relation to environmental and spatial predictors. Processes determining metacommunity structure differed between the components of beta diversity and among taxonomic and functional diversity. While taxonomic beta diversity was further accounted by both environmental and spatial predictors, functional beta diversity responded more strongly to spatial predictors. These two contrasting patterns were different to what we had predicted, suggesting that while there is a taxonomic turnover mediated by environmental filters, the spatial distance promotes the trait dissimilarity between sites. In addition, our data confirm that neutral and niche-based processes operate on anuran metacommunities even at short geographic scales. Our results reinforce the idea that studies aiming to evaluate the patterns of structure in metacommunities should include different facets of diversity so that better interpretations can be achieved.

The relative contributions of environmental and spatial predictors in the patterns of taxonomic and functional anuran beta diversity were examined in 33 ponds of a metacommunity along the coast of south Brazil. Anurans exhibit limited dispersion ability and have physiological and behavioural characteristics that narrow their relationships with both environmental and spatial predictors. So, we expected that neutral processes and, in particular, niche-based processes could have similar influence on the taxonomic and functional beta diversity patterns. Variation partitioning and distance-based methods (db-RDA) were conducted with presence/absence and abundance data to examine taxonomic and functional facets and components (total, turnover and nestedness-resultant) in relation to environmental and spatial predictors.Processes determining metacommunity structure were similar between the components of beta diversity but differed among taxonomic and functional diversity.While taxonomic beta diversity was further accounted by environmental predictors, functional beta diversity responded more strongly to spatial predictors. These patterns were more evident when assessed through abundance data. These opposing patternswere contrary to what we had predicted, suggesting that while there is a taxonomic turnover mediated by environmental filters, the spatial distance promotes the trait dissimilarity between sites. Our results reinforce the idea that studies aiming to evaluate the patterns of structure in metacommunities should include different facets of diversity so that better interpretations can be achieved. Material and Methods Ethics statementCollection permits were provided by Instituto Chico Mendes de Conservação da Biodiversidade (ICMBio) (authorization 55409). Field studies did not involve endangered or protected species. We restricted manipulation of animals in the field to minimal as we sampled just specimes restricted in the collection units (see the section 2.3). Specimens collected were identified, measured and immediately released after these procedures in the same pond where they were sampled. All sampling procedures were reviewed and specifically approved as part of obtaining the field permits by ICMBio (see above). Study AreaThis study was done in Lagoa do Peixe National Park (PNLP; 31°02_-31°48_S; 50°77_-51°15_W; figure 1), the only Ramsar site in southern Brazil [43]. With a length of 64 km and an average width of 6 km, the PNLP comprises over 34,000 hectares of protected wetlands, integrating the Coastal Plain of the State of Rio Grande do Sul, one of the regions of southern Brazil with higher concentration of wetlands [44].The climate is subtropical humid, and temperatures range between 13 °C and 24 °C with annual average of 17.5 °C. The mean annual precipitation varies between 1200 and 1500 mm [45].

doi: bioRxiv preprint length suggests differences in dispersal and trophic segregation between species.

Herein, we provide new occurrence records of Scinax nasicus (Cope, 1862) for the state of Rio Grande do Sul, Southern Brazil. All new records here provide are located on Southern half of the state. Besides this, we provide the first record for species in Brazilian coastal zone. Those records improve considerably our knowledge regarding species distribution in Southern Brazil.Keywords: Brazil subtropical, Pampa Domain, Scinax ruber clade. Primeiro registro da perereca-de-banheiro Scinax nasicus (Cope, 1862) na costa do Brasil e novos registros para o estado do Rio Grande do Sul ResumoAqui, nós fornecemos novos registros de ocorrência de Scinax nasicus (Cope, 1862) para o estado do Rio Grande do Sul, Sul do Brasil. Todos os novos registros aqui fornecidos estão localizados na metade sul do estado. Além disso, nós fornecemos o primeiro registro para a espécie na zona costeira brasileira. Esses registros melhoram consideravelmente o nosso conhecimento sobre a distribuição da espécie no Sul do Brasil. Palavras-chave: Brasil subtropical, Domínio do Pampa, clado Scinax ruber.Scinax nasicus (Cope, 1862) is morphologically characterized by having a flattened body, rounded snout in dorsal view and truncated in side view, and it has a relatively small body size (~35 mm CRC) by comparison with other species of the Scinax ruber clade (Pombal Junior et al., 1995). Even so, species may be confounded with other sympatric species of S. ruber clade, such Scinax fuscovarius (Lutz, 1925), Scinax granulatus (Peters, 1871) and Scinax perereca (Pombal Junior et al., 1995). When available, advertisement call is one of the more effective tools to confirm species identification once that it has shorter duration compose by a single note by comparison with their congeners.