The benthic communities of fringing and mushroom-shaped shallow-water reefs of the Abrolhos region (southern coast of Bahia) were surveyed. Line transects were used to estimate coral and algal percentage cover. Mussismilia braziliensis is the most conspicuous coral species in the majority of the communities surveyed, but turf algal make up the dominant cover in all but one studied reef. In general, communities on mushroom-shaped reefs have higher diversity and higher coral cover than on fringing reefs. For both reef morphologies, the coral to alga cover ratio does. not show marked differences between annual surveys, despite the high productivity characteristic of the dominant algal species.

This study investigates the reef fish community structure of the world’s smallest remote tropical island, the St Peter and St Paul’s Archipelago, in the equatorial Atlantic. The interplay between isolation, high endemism and low species richness makes the St Peter and St Paul’s Archipelago ecologically simpler than larger and highly connected shelf reef systems, making it an important natural laboratory for ecology and biogeography, particularly with respect to the effects of abiotic and biotic factors, and the functional organisation of such a depauperate community. Boosted regression trees were used to associate density, biomass and diversity of reef fishes with six abiotic and biotic variables, considering the community both as a whole and segregated into seven trophic groups. Depth was the most important explanatory variable across all models, although the direction of its effect varied with the type of response variable. Fish density peaked at intermediate depths, whereas biomass and biodiversity were respectively positively and negatively correlated with depth. Topographic complexity and wave exposure were less important in explaining variance within the fish community than depth. No effects of the predictor biotic variables were detected. Finally, we notice that most functional groups are represented by very few species, highlighting potential vulnerability to disturbances.

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This study, performed over the years 1999–2003, analyzed the species composition, spatial distribution and ecological aspects of macroalgal assemblages on Atol das Rocas reef, located 266 km off northeastern Brazil. It is the sole atoll in the South Atlantic and is almost completely built of coralline algae. Forty-seven new occurrences of macroalgae were recorded. Adding these to the previous studies, 143 taxa are now known for the local marine flora, with the Rhodophyta as the dominant group. New finds were mainly on the fore reef and in reef pools. The inner habitats (the reef flat, internal ridge and inner pools) harbored fewer macroalgal species than the outer habitats (the reef front, reef crest crevices and outer pools). Inner habitats are subject to prolonged desiccation and solar irradiation stress together with abrupt changes in temperature and salinity controlled by the water oscillations of the mesotidal regime within the atoll; the outer habitats are less affected by these short temporal impacts and are mainly governed by oceanic forcing. Atol das Rocas harbors some species unknown in other Brazilian waters, but these are common in Caribbean reef waters.

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About 80% of the human adult population is infected with HSV-1. Although there are many anti-HSV-1 drugs available (acyclovir, ganciclovir, valaciclovir, foscarnet), their continuous use promotes the selection of resistant strains, mainly in ACV patients. In addition to resistance, the drugs also have toxicity, particularly when administration is prolonged. The study of new molecules isolated from green algae with potential antiviral activity represents a good opportunity for the development of antiviral drugs. Caulerpin, the major product from the marine algae Caulerpa Lamouroux (Caulerpales), is known for its biological activities such as antioxidant, antifungal, acetylcholinesterase inhibitor (AChE) and antibacterial activity. In this work, we show that caulerpin could be an alternative to acyclovir as an anti-HSV-1 drug that inhibits the alpha and beta phases of the replication cycle.

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Sampling methods for rocky shoresThis study compares three sampling methodologies of rocky shore communities: visual estimation, point intercept quadrats and destructive sampling. Visual estimation was performed in two sizes of sampling device and, point intercept quadrats was done with different numbers of marked dots. The sampling took place on the rocky shore of Forno beach, Búzios, RJ, in two different algae belts; one whose the landscape is characterized by Amphiroa sp., the other, Sargassum furcatum was the most conspicuous species. The data were analyzed by ANOVA and Kruskal-Wallis tests. Number of species, total percent cover, diversity and evenness indices were the variables used. The results shown that in general the methods compared were not statistically different one from the other in this community. There were significative differences between the methods when comparison was made between nondestructive and destructive sampling. However, smaller areas of sampling devices and fewer intercept points decreased the sampling power in respect of sampling species richness. All of the methods studied were considered similar in concern of total cover index and of diversity and evenness indices, with some exceptions. Present data are useful only for rocky communities with similar profiles. The choice of method must be made in regard of each situation.Key words: sampling methods, rocky shore, phytobenthos, Búzios, RJ. RESUMOO presente estudo compara três metodologias de amostragem de costão rochoso: estimativa visual, pontos de interseção e raspagem total do substrato. No método de estimativa visual, variou-se o tamanho do amostrador e, no de pontos de interseção, o número de pontos marcados. As amostras foram coletadas no costão da praia do Forno, Búzios, RJ, em duas faixas, uma dominada fisionomicamente por Amphiroa sp. e a outra, por Sargassum furcatum. Foram aplicados testes de ANOVA e KruskalWallis aos resultados encontrados, utilizando-se como variáveis os índices bionômicos de número de espécies, porcentagem total de recobrimento, índice de diversidade e índice de uniformidade. Os resultados provaram que nenhuma metodologia de amostragem semelhante mostrou-se estatisticamente diferente da outra. Existe diferença quando se comparam os métodos não-destrutivos ao método destrutivo. No entanto, amostradores com menor área ou menor número de pontos não amostram bem o índice número de espécies. Os métodos não apresentaram diferença significativa em relação à cobertura total e aos índices de diversidade e uniformidade, salvo algumas exceções. Os resultados do presente trabalho são aplicáveis apenas a comunidades de costão rochosos com perfis similares ao da comunidade estudada. A escolha do método deve ser considerada para cada situação.Palavras-chave: metodologia de amostragem, costão rochoso, fitobentos, Búzios, RJ.