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Questions: Is macrophyte beta diversity in temporary ponds generated mainly by turnover along a latitudinal gradient? Is macrophyte beta diversity more strongly correlated with differences in local environmental conditions and climate than geographical distances? Are hydrophytes and helophytes correlated with distinct environmental drivers?Location: Southern Brazilian Coastal Plain. Methods:Macrophyte communities were studied in 24 ponds distributed along a latitudinal gradient. Beta diversity was calculated with the Sorensen dissimilarity index (and further partitioned into turnover and nestedness components). We assessed the individual correspondence of macrophyte beta diversity with local (water quality and habitat structure; after pre-selection procedures on each explanatory matrix) and climatic environmental drivers, as well as with the geographical distances, through Mantel correlation tests. Partial Mantel tests were carried out to assess the correspondence of beta diversity with the climatic drivers and geographical distances while controlling for the effect of each explanatory matrix. Separate assessments were carried out for subsets of hydrophytes and helophytes.Results: Macrophyte beta diversity was mainly generated by turnover. Mantel tests detected significant correlations of macrophyte beta diversity with climatic rather than with local environmental drivers. Partial Mantel tests detected significant relationships only between macrophyte beta diversity and climate (rather than geographical distances). Helophytes were more strongly correlated with climate than hydrophytes, and geographical distances were significantly correlated to hydrophyte beta diversity only. Conclusions:Our results indicate that macrophyte communities in southern Brazilian coastal temporary ponds are mainly assembled by species sorting processes, although the contribution of each assembly mechanism differed between functional groups (spatial processes were more important for hydrophytes than helophytes). The distinct relationships of hydrophytes and helophytes with climate suggest different sensitivity of each functional group to environmental changes in temporary ponds. K E Y W O R D S functional groups, growth forms, helophytes, hydrophytes, macrophytes, metacommunities, nestedness, turnover 282 | Additional supporting information may be found online in the Supporting Information section at the end of the article. Appendix S1 Local environmental drivers measured at each sampling site Appendix S2 Values of the WorldClim bioclimatic variables obtained for each sampling site Appendix S3 Relationships between the bioclimatic variables and the first four axes of the principal component analysis Appendix S4 Workflow of the statistical procedures undertaken for the assessment of the relationships between macrophyte beta diversity and environmental drivers and geographical distances Appendix S5 List of aquatic plant species and their corresponding functional groups recorded in the study Appendix S6 Outputs of the partial multi-variate...

Aposematism in an anti-predation mechanism that occurs when animals exhibit conspicuous signals, which are often of a contrasting color patterns, to alert potential predators of their unpalatability or toxicity. This study aims to test (in a short period) the effectiveness of aposematic coloration by comparing the predatory attack upon snakes models with and without an alert coloration on the body. To simulate snakes, we made 80 greenish plasticine snake models. Half of the models had a red strip on the dorsal part of the body, imitating an aposematic coloration. The other half of the models had only a greenish tint. The models were exposed to predators for 12 hours in an area with countryside vegetation.. Among the 20 models showing signs of predation, 65% were purely greenish models and 35% were models with red coloration on the back. Attaks at extremities (head and tail) were meaningly more frequent on models with red coloration. Our results suggest the efficiency of red coloration as a warning sign and anti-predation mechanism, since the models with red coloration, imitating aposematic preys, were less preyed and were attacked preferentially at the extremities, which suggests caution by the predator.

RESUMO O estudo do gênero Oenothera L. no município de Santa Maria, Rio Grande do Sul, Brasil, revelou a ocorrência de cinco espécies. O trabalho apresenta chave para diferenciação das espécies, ilustrações e dados de suas distribuições geográficas. Palavras-chave: Oenothera, Onagraceae, Santa Maria, Rio Grande do Sul. ABSTRACT [The genus Oenothera L. (Onagraceae) in the municipality of Santa Maria, Rio Grande do Sul, Brazil].The study of the genus Oenothera L. in the municipality of Santa Maria, Rio Grande do Sul state, Brazil, confirmed the occurrence of five species. A analytical key to differenciate species is provided, as well as illustrations and data about the geographic distribution.

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