O presente estudo descreve a associação de nematódeos da Baía de Tamandaré (Brasil), praia arenosa tropical típica, durante as marés (baixa, enchente, alta e vazante) de dois ciclos de maré consecutivos, em quatro meses diferentes do ano (Maio, Julho, Setembro e Novembro). A associação de nematódeos foi dominada por Metachromadora e Perepsilonema e variou significativamente entre meses e marés. Densidades foram mais baixas em julho e as mudanças na associação ocorreram durante meses de transição entre chuvoso e seco mostrando a influência do ciclo de chuvas. No ciclo de maré a enchente e vazante pareceram exercer a maior influência, embora os padrões não fossem muito claros. Recomenda-se que os estudos devam ser feitos ao nível de gêneros/espécies para melhor compreensão dos padrões das associações de nematódeos durante ciclos de marés.

The present study describes the nematode assemblage of the bay of Tamandaré (Brazil), a tropical sandy beach, during the low, flood, high and ebb tides of two consecutive tidal cycles in four different months of the year (May, July, September and November). The nematode assemblage was dominated by Metachromadora and Perepsilonema and varied significantly between months and tides. Densities were lower in July, and changes in assemblage structure occurred during the transitional periods between rainy and dry months, which showed the influence of rainfall. Flood and ebb tides appeared to exercise the greatest influences over the tidal cycle, although the patterns were not very clear. Identification at genera/species level is recommended for future studies, to better understand the patterns of nematode assemblages during tidal cycles.

Los manglares son ecosistemas de transición entre los ambientes terrestres y marinos, y se distinguen por la gran abundancia de animales, plantas y hongos. Aunque los macrohongos se encuentran en diferentes tipos de hábitat, incluidos los manglares, poco se sabe acerca de la estructura de su comunidad y dinámica. Por lo tanto, el objetivo de este estudio fue analizar la diversidad de macrohongos en los manglares de Brasil y su relación con la precipitación y área de recolección. Se realizaron un total de 32 salidas de campo entre 2009 y 2010, y los macrohongos fueron estudiados en cuatro transectos de 250×40m: Timbó y Canal de Santa Cruz en la costa norte y Maracaípe y Ariquindá en la costa sur. Todos los basidiomas encontrados a lo largo de los transectos se colocaron deshidratados en bolsas de papel, y se identificaron con ayuda de la literatura preexistente. Se encontró que las zonas del norte predominantemente presentaron Avicennia schaueriana, mientras Rhizophora mangle domina en transectos del sur. Se recolectaron un total de 275 especímenes y 33 especies, 28 géneros, 14 familias y seis órdenes estuvieron representados. Abundancia y riqueza de especies en general no varió significativamente entre las áreas, pero si varió en el tiempo, siendo mayor durante la estación lluviosa. Se observaron diferencias sutiles en la composición a través del tiempo y entre áreas, probablemente debido a las variaciones en la presencia de las especies de plantas. Otros estudios con recolectas durante los meses de mayor precipitación en transectos dominados por diferentes plan- tas de manglar en el mismo ecosistema son deseables para acceder a la diversidad de la micobiota.

Mangroves are transitional ecosystems between terrestrial and marine environments, and are distinguished by a high abundance of animals, plants, and fungi. Although macrofungi occur in different types of habitat, including mangroves, little is known about their community structure and dynamic. Therefore the aim of this study was to analyze the diversity of macrofungi in a number of Brazilian mangroves, and the relationship between such diversity, precipitation and area of collection. A total of 32 field trips were undertaken from 2009 to 2010, and macrofungi were studied in four 250×40m transects: Timbó and Santa Cruz Channel on the Northern coast, and Maracaípe and Ariquindá on the Southern coast. All basidiomata found along the transects were placed in paper bags, air-dried and identified using existing literature. It was found that Northern areas predominantly featured Avicennia schaueriana mangroves, while Rhizophora mangle dominated in Southern transects. A total of 275 specimens were collected, and 33 species, 28 genera, 14 families and six orders were represented. Overall abundance and species richness did not vary significantly among areas, but varied according to time, being higher during the rainy season. Subtle differences in composition were observed over time and between areas, probably due to variations in plant species occurrence. Further studies with collections during months of greater precipitation in transects dominated by different mangrove species of the same ecosystem are suggested to assess the overall diversity of mycobiota in these ecosystems.

Nineteen taxa of Mucorales, belonging to Absidi, Apophysomyces, Cunninghamella, Fennellomyces, Lichtheimi, Mucor, Mycotypha, Rhizopus and Syncephalastrum were isolated from 36 composite soil samples in three semiarid areas in the State of Pernambuco (Triunfo, Cabrobó and Belém de São Francisco), Northeast Brazil, which are characterized by Caatinga vegetation. Triunfo is preserved, whereas Cabroró and Belém de São Francisco are experiencing low and severe desertification processes, respectively. Mucorales were isolated in Petri dishes in triplicate from 5 mg samples of soil placed on the surface of wheat germ agar plus chloramphenicol and Cercobin [Dimethyl 4,49-(103 phenylene) bis (3-thioallophanate)] medium. The plates were left on a bench at room temperature (28 ± 2 ºC) for 72 h of alternating dark and light periods. Absidia cylindrospora presented the highest amount of CFU/g of soil, followed by L. hyalospor, C. phaeospora and C. echinulata var. echinulata. The latter, and R. microsporus var. microsporus, presented the highest frequencies of occurrence. Soils from Triunfo showed higher diversity of Mucorales than the samples from the other areas, although without differing statistically in relation to species richness. The communities of Mucorales from the degraded areas were more similar, while that from the preserved area was quite different. Most of the identified specimens have been commonly isolated from soil in other Brazilian regions, which indicates that they are not endemic of the semiarid. Eleven taxa are registered for the first time in this ecosystem, while F. heterothallicus is reported for the first time in Brazil.

A ocorrência dos camarões fantasma Biffarius biformis (Biffar 1971) e Biffarius fragilis (Biffar 1970) no nordeste do Brasil têm sido considerada duvidosa, porque o registro original (Carvalho et al. 1997) realizado em resumo durante uma conferência regional não pode ser considerado válido. Neste trabalho, o estudo dos espécimens examinados por Carvalho et al. (1997), combinados com o material coletado mais recentemente, confirma a presença dessas duas espécies na costa brasileira e no sudoeste do Atlântico. São fornecidas novas informações taxonômicas, ecológicas e ilustrações.

Previous records of the callianassid ghost shrimps Biffarius biformis (Biffar, 1971) and Biffarius fragilis (Biffar, 1970) from Pernambuco, northeastern Brazil, were considered as doubtful, because their original record (Carvalho et al. 1997) in a conference abstract cannot be considered as a valid publication. The original material examined by Carvalho et al. (1997) combined with the more recently collected material of B. biformis and B. fragilis, confirm the presence of these two species in Brazil and the southwestern Atlantic. Taxonomic and ecological remarks, as well as illustrations, are provided for both species.

A estrutura populacional (machos, fêmeas e juvenis) e densidade de Mesacanthion hirsutum Gerlach foram estudadas durante as marés (baixa, enchente, alta e vazante) de dois ciclos de maré consecutivos, em quatro meses diferentes do ano (Maio, Julho, Setembro e Novembro). As variações de densidade de Mesacanthion hirsutum mostraram associação com o ciclo de chuvas, com densidades mais baixas durante Julho e Setembro e significativamente maiores em Maio e Novembro. A estrutura populacional constituiu-se em sua maior parte por juvenis indicando uma reprodução continua durante todo o período de estudo. Não foram encontradas diferenças significativas entre os períodos claros e escuros do dia, contudo maiores densidades foram detectadas durante as marés altas e vazantes demonstrando que a espécie pode estar se dispersando através da coluna d'água e/ou migrando dentro do sedimento.

The population structure (males, females and juveniles) and density of Mesacanthion hirsutum Gerlach were studied during the tides (low, flood, high and ebb) of two consecutive tidal cycles in four different months of the year (May, July, September and November). Mesacanthion hirsutum density variations showed association with the rainfall cycle, with lower densities during July and September and significantly higher values in May and November. The population structure was constituted mostly by juveniles indicating a continuous reproduction during all the studied period. There were no significant differences between light and dark periods of the day, however, the higher densities detected during the high and ebb tidal stages demonstrate that this species could be dispersing through the water column and/or migrating within the sediment.

Thirty-eight taxa of Zygomycetes distributed in 15 genera were recorded from tapir (Tapirus terrestris), camel (Camelus bactrianus), horse (Equus caballus), deer (Cervus elaphus), agouti (Dasyprocta aguti), donkey (Equus asinus), llama (Llama glama) and waterbuck (Kobus ellipsiprymnus) dung collected at the Reserva Ecológica de Dois Irmãos located in Recife, State of Pernambuco, Northeast Brazil. The samples were collected on a monthly basis from June 2005 to May 2006, taken to the laboratory and incubated in moist chambers. Higher number of taxa was observed in the excrements of tapir, followed by deer and donkey. The highest number of species was detected for Mucor, followed by Pilobolus. Statistical analyses showed significant differences in richness of Zygomycetes taxa between the herbivore dung types. Differences of species composition, however, were weak. Seasonality influenced the Zygomycetes species composition but not its richness. Variations in taxa composition between ruminants and non-ruminants dung were non significant.

Variações espaço-temporais da biomassa do microfitobentos foram investigadas nos estuários dos rios Botafogo e Siri em Pernambuco, Brasil. As amostragens foram realizadas em baixa-mar (bimestralmente) de fevereiro a dezembro de 2003. Em cada estuário foram determinadas três estações de amostragem no médio- e no infralitoral. Fortes variações espaciais e temporais foram verificadas nas concentrações tanto de clorofila-a como de feopigmentos. No estuário do Botafogo, a clorofila-a teve 34% do total da sua variação explicada pela análise de regressão múltipla (MRA) baseada nas concentrações de nitrogênio e de fósforo, enquanto no estuário do Siri somente 16% dessa variação foi explicada pela MRA baseada na concentração de nitrogênio. Feopigmentos apresentou 39% de sua variação total explicada pela MRA baseada na concentração de nitrogênio e na salinidade no estuário do Botafogo; enquanto no Siri a MRA explicou 58% da variação total baseada somente na concentração de nitrogênio. Nitrogênio foi discriminado como o fator mais importante para explicar as variações do microfitobentos no estuário do rio Botafogo. Os resultados do presente trabalho ressaltam o papel dos nutrientes e sugerem que ambos estuários apresentam evidências de eutrofização.

Spatio-temporal variations of microphytobenthic biomass were investigated in the Botafogo and Siri estuaries, Pernambuco - Brazil. Samples were taken during low water (bi-monthly) from February to December, 2003. Three sampling stations were located in each estuary, in both midlittoral and sublittoral areas. Clear spatial and temporal variations were found for both chlorophyll-a and phaeopigment concentrations. In Botafogo, chlorophyll-a had 34% of total variation explained by MRA from nitrogen and phosphorus concentrations, while only 16% of total variation was thus explained from nitrogen concentration in the Siri estuary. Phaeopigments had 39% of total variation explained by MRA from nitrogen concentration and salinity in the Botafogo estuary and 58% of total variation was similarly explained from nitrogen concentration in the Siri estuary. Nitrogen was discriminated by the b coefficients as the most important factor in the explanation of the microphytobenthic pigments variations in the Botafogo estuary. The data of this study emphasize the role of nutrients and suggest that both estuaries show evidence of eutrophication.