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ABSTRACT. We use two taxonomic indexes to assess the variability of the taxonomic structure and diversity of the ichthyofauna of two low-energy environments in southern Brazil and to compare the temporal patterns of these two ichthyofaunas. Sampling was conducted in the infralittoral zones of Maciel (Paranaguá Bay, PR) and Indio Beach (Norte Bay of Florianópolis, SC). A fyke net was set up at a depth of 0.5 to 2.0 m and left in place for 48 h for each of the samplings. A total of two diurnal and two nocturnal samplings were conducted monthly per one year. The ichthyofaunas at the two sites exhibited similar temporal dynamics, with their abundance and biomass presenting a tendency to increase with increasing temperature during the spring and summer months. A total of 113 species were captured, of which 47 were present at both sites. Harengula clupeola, Sphoeroides testudineus and S. greeleyi were especially abundant at both sites. The co-occurring species displayed similar day and night occupancy trends. In all seasons, the obtained values for the average taxonomic distinctness and variation in taxonomic distinctness were within the confidence intervals. The seasonal reproduction and recruitment patterns led to slight changes in taxonomic distinctness during the year, which were within the expected intervals. Keywords: ichthyofauna, taxonomic distinctness, nycthemeral dynamics, sheltered beach, southern Brazil.Comparación de los patrones taxonómicos y temporales de la ictiofauna capturada con red fyke en dos ambientes protegidos en el sur de Brasil RESUMEN. Se utilizaron dos índices taxonómicos para evaluar la variabilidad de la estructura taxonómica y diversidad de la ictiofauna en dos ambientes de baja energía en el sur de Brasil, así como para comparar sus patrones temporales. Los muestreos se realizaron en las zonas infralitoral de Maciel (Bahía de Paranaguá, PR) e Indio Beach (Bahía Norte, SC). Se instaló una "fyke net" a una profundidad de 0,5 a 2 m, durante 48 h, para cada uno de los muestreos. Durante un año se realizó un total de dos muestreos diurnos y dos nocturnos. La ictiofauna en los dos sitios mostró dinámicas temporales similares, con su abundancia y biomasa presentando una tendencia a aumentar con el incremento de la temperatura durante los meses de primavera y verano. Un total de 113 especies fueron capturadas, de los cuales 47 estuvieron presentes en ambos sitios. Harengula clupeola, Sphoeroides testudineus y S. greeleyi fueron especialmente abundantes en ambos sitios. Las especies coexistentes mostraron tendencias similares de ocupación tanto de día como de noche. En todas las estaciones, los valores obtenidos para la distinción taxonómica media y para la variación en la distinción taxonómica estuvieron dentro de los intervalos de confianza. Los patrones de reproducción y reclutamiento estacionales llevaron a ligeros cambios en la distinción taxonómica durante el año, que estuvieron dentro de los intervalos esperados. Palabras clave: ictiofauna, distinción taxonómica, dinámica nictimeral, play...

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A B S T R A C TInterpreting fish community records is challenging for several reasons, including the lack of past ichthyofauna data, the cyclical temporal variations in the community, and the methodology employed, which usually underestimates fish assemblages. The objective of this study was to describe short-scale and meso-scale (nycthemeral period and months, respectively) temporal variations in the ichthyofauna composition and structure of a sheltered beach of Baía Norte (Florianópolis, Santa Catarina state, Brazil), using a capéchade net. Samples were collected monthly for a period of 48 hours. During the period from December 2010 to November 2011, a total of 19,302 individuals belonging to 89 species and 39 families were captured. The number of individuals that were sampled during the day and/or night was dependent on the sampling month. On average, the daytime assemblage was more abundant and different in structure and composition than the nighttime assemblage. Of the eight species that had the highest Index of Relative Importance (%IRI), five had higher variations (ANOVA F) between the day and night than between the months. This finding reinforced the need for sampling during both the day and night. The capéchade net effectively captured demersal and pelagic individuals in a broad range of sizes. R E S U M OA interpretação dos registros da comunidade ictíica têm se mostrado um desafio por diversos motivos, entre eles a falta de dados pretéritos, existência de variações temporais cíclicas na comunidade e pelos métodos utilizados que geralmente subamostram a assembleia. Neste sentido, o objetivo do presente trabalho foi descrever o padrão de variação temporal (nictemeral e mensal) na composição e na estrutura da ictiofauna de uma praia abrigada da Baía Norte de Florianópolis, usando uma rede capéchade. Coletas foram realizadas mensalmente, integrando um período de 48 horas/mês. Durante os meses de dezembro de 2010 a novembro de 2011, 19302 indivíduos distribuídos em 89 espécies e 39 famílias foram capturados. O número de indivíduos capturados durante o dia e/ou noite foi dependente do mês de coleta. Em média, a assembleia foi mais abundante durante o dia, diferindo em estrutura e composição do período da noite. Das oito espécies com maior Índice de Importância Relativa (IRI%), cinco apresentaram maior variação (F ANOVA) entre o dia e a noite do que a verificada entre os meses, o que reforça a necessidade de amostragens durante o dia e a noite. A rede capéchade foi eficiente na captura de indivíduos demersais e pelágicos com ampla faixa de tamanho.

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In the present paper, we document a recent record of the Bannerfish, Heniochus acuminatus, an Indo-Pacific species, in the southwest Atlantic Ocean and comment on biological aspects of the Azores Chromis, Chromis limbata, an invasive reef fish in the western Atlantic Ocean. We suggest that investigations of invasive species along the Brazilian coast can use data provided by citizen science, strengthening the non-native reef fish control strategies.

A single Pomacanthus maculosus was filmed during a scuba diving survey on a rocky reef from southern Brazil. The body shape and coloration pattern confirmed the species identification. The biological and ecological characteristics of P. maculosus and the long distance of Brazil from its original distribution strongly suggest of an anthropogenic pathway of dispersion.

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