Bycatch of Asteroidea from shrimp trawl fishery in the southwestern Atlantic Ocean ­ Brazil

Shrimp trawling is considered a significant negative impact on the marine ecosystem, especially on the benthic community. Sea stars (Echinodermata: Asteroidea) are one of the most affected groups by unintentional catches. This study was performed at the Santana Archipelago, a Marine Protected Area in the northern region of Rio de Janeiro State, between 2008-2009. Sea stars accidentally caught by trawling were collected during open and closed season of the shrimp fisheries (Xiphopenaeus kroyeri) at depths of 5-60 m. A generalized linear zero-inflated model was applied to test for differences in capture between fishing seasons and depths. A total of 158 sea star specimens were captured. These specimens were identified as Asterina stellifera, Astropecten acutiradiatus, Astropecten brasiliensis, Astropecten cingulatus, Luidia alternata alternata, Luidia clathrata, Luidia ludwigi scotti, Luidia senegalensis. The sea stars A. brasiliensis and L. senegalensis are currently considered as vulnerable species in the Brazilian official list of threatened species. The higher capture of sea stars was shown in deepest areas, and there was no significant difference in the number of specimens between seasons. This is the first study about asteroids accidentally captured by shrimp trawling.(AU)

A new species and record of Biancolina Della Valle, 1893 (Amphipoda, Senticaudata, Ampithoidae) from the Southwestern Atlantic

Here we describe a new species of Biancolina from Pernambuco, Brazil, found in association with the brown algae Sargassum spp., between 0.5 and 1.0 m depth. The new species differs from its congeners mainly by the following combination of characters: antenna 1 twice the length of antenna 2, lacinia mobilis present in both mandibles, article 4 of the maxilliped bulbose; coxa 6 with anteroventral lobe well developed as in posteroventral lobe, peduncle of uropod 1 weakly setose, palm of pereopods 5-7 lacking robust seta. This is the first record of Biancolina from the southwestern Atlantic.(AU)

Towards a review of the decapod crustacea from the remote oceanic archipelago of Trindade and Martin Vaz, south Atlantic Ocean: new records and notes on ecology and zoogeography

The remoteness of the Trindade and Martin Vaz young volcanic archipelago (TMV) raises questions about the source of its marine benthic fauna and levels of endemism. Addressing these questions requires a comprehensive knowledge of the taxonomic composition of the marine fauna of the islands. A five-year survey in the shallow marine waters (up to 30 m) and a literature review on the data published for TMV have been conducted to document the biodiversity of the benthic fauna. Here we report on ten new records of decapod crustaceans from TMV: Gnathophyllum americanum and Thor amboinensis are circumtropical in distribution, whereas Stenopus hispidus, Gnathophylloides mineri and Parribacus antarcticus are disjunct circumtropical species as their distribution in the Atlantic Ocean is limited eastwardly to TMV or Ascension Island (S. hispidus), therefore, do not extending into the eastern Atlantic. Gnathophyllum circellum and Thor manningi are western Atlantic species, with G. circellum previously known only from the Caribbean Sea. Pontonia manningi, Tuleariocaris neglecta and Enoplometopus antillensis are amphi-Atlantic in distribution. Two of the above species are recorded from the southwestern Atlantic for the first time: Gnathophyllum circellum and Tuleariocaris neglecta. These new records corroborate that the marine benthic invertebrate fauna of the TMV archipelago is actually a [...]

O grande isolamento geográfico do jovem arquipélago vulcânico Trindade e Martin Vaz (TMV) suscita questionamentos sobre a origem e os níveis de endemismo de sua fauna. Entretanto, a abordagem destas questões requer o conhecimento abrangente da composição taxonômica da fauna bentônica marinha de TMV. Com o intuito de documentar a biodiversidade em TMV foram efetuadas amostragens da fauna de invertebrados bentônicos durante cinco anos consecutivos do entre-marés até profundidades de 30 m. Nesta oportunidade apresentamos dez novos registros de crustáceos Decapoda para TMV, juntamente com comentários ecológicos e notas zoogeográficas. Gnathophyllum americanum e Thor amboinensis são espécies circumtropicais, enquanto que Stenopus hispidus, Gnathophylloides mineri e Parribacus antarcticus são espécies circumtropicais disjuntas na medida em que sua distribuição no oceano Atlântico encontra-se limitada à leste pelas ilhas TMV ou Ascensão (S. hispidus), consequentemente, não se estendendo ao Atlântico oriental. Gnathophyllum circellum e Thor manningi são espécies do Atlântico ocidental; G. circellum era conhecida previamente apenas do Mar do Caribe. Pontonia manningi, Tuleariocaris neglecta e Enoplometopus antillensis são espécies anfi-Atlânticas. Estes novos registros para TMV corroboram a ideia de que a fauna marinha bentônica de TMV constitui-se em um mosaico de espécies atlântico-ocidentais, atlântico-orientais, centro-atlânticas (insulares), anfi-Atlânticas, endêmicas e circumtropicais. O componente atlântico ocidental tem forte influência na formação faunística de TMV.

Towards a review of the decapod crustacea from the remote oceanic archipelago of trindade and martin vaz, south atlantic ocean: new records and notes on ecology and zoogeography

ABSTRACT The remoteness of the Trindade and Martin Vaz young volcanic archipelago (TMV) raises questions about the source of its marine benthic fauna and levels of endemism. Addressing these questions requires a comprehensive knowledge of the taxonomic composition of the marine fauna of the islands. A five-year survey in the shallow marine waters (up to 30 m) and a literature review on the data published for TMV have been conducted to document the biodiversity of the benthic fauna. Here we report on ten new records of decapod crustaceans from TMV: Gnathophyllum americanum and Thor amboinensis are circumtropical in distribution, whereas Stenopus hispidus, Gnathophylloides mineri and Parribacus antarcticus are disjunct circumtropical species as their distribution in the Atlantic Ocean is limited eastwardly to TMV or Ascension Island (S. hispidus), therefore, do not extending into the eastern Atlantic. Gnathophyllum circellum and Thor manningi are western Atlantic species, with G. circellum previously known only from the Caribbean Sea. Pontonia manningi, Tuleariocaris neglecta and Enoplometopus antillensis are amphi-Atlantic in distribution. Two of the above species are recorded from the southwestern Atlantic for the first time: Gnathophyllum circellum and Tuleariocaris neglecta. These new records corroborate that the marine benthic invertebrate fauna of the TMV archipelago is actually a mosaic of amphi-Atlantic, eastern Atlantic, central Atlantic (insular), endemic and circumtropical species, with a strong western Atlantic component.

RESUMO O grande isolamento geográfico do jovem arquipélago vulcânico Trindade e Martin Vaz (TMV) suscita questionamentos sobre a origem e os níveis de endemismo de sua fauna. Entretanto, a abordagem destas questões requer o conhecimento abrangente da composição taxonômica da fauna bentônica marinha de TMV. Com o intuito de documentar a biodiversidade em TMV foram efetuadas amostragens da fauna de invertebrados bentônicos durante cinco anos consecutivos do entre-marés até profundidades de 30 m. Nesta oportunidade apresentamos dez novos registros de crustáceos Decapoda para TMV, juntamente com comentários ecológicos e notas zoogeográficas. Gnathophyllum americanum e Thor amboinensis são espécies circumtropicais, enquanto que Stenopus hispidus, Gnathophylloides mineri e Parribacus antarcticus são espécies circumtropicais disjuntas na medida em que sua distribuição no oceano Atlântico encontra-se limitada à leste pelas ilhas TMV ou Ascensão (S. hispidus), consequentemente, não se estendendo ao Atlântico oriental. Gnathophyllum circellum e Thor manningi são espécies do Atlântico ocidental; G. circellum era conhecida previamente apenas do Mar do Caribe. Pontonia manningi, Tuleariocaris neglecta e Enoplometopus antillensis são espécies anfi-Atlânticas. Estes novos registros para TMV corroboram a ideia de que a fauna marinha bentônica de TMV constitui-se em um mosaico de espécies atlântico-ocidentais, atlântico-orientais, centro-atlânticas (insulares), anfi-Atlânticas, endêmicas e circumtropicais. O componente atlântico ocidental tem forte influência na formação faunística de TMV.

Towards a review of the decapod crustacea from the remote oceanic archipelago of Trindade and Martin Vaz, south Atlantic Ocean: new records and notes on ecology and zoogeography

The remoteness of the Trindade and Martin Vaz young volcanic archipelago (TMV) raises questions about the source of its marine benthic fauna and levels of endemism. Addressing these questions requires a comprehensive knowledge of the taxonomic composition of the marine fauna of the islands. A five-year survey in the shallow marine waters (up to 30 m) and a literature review on the data published for TMV have been conducted to document the biodiversity of the benthic fauna. Here we report on ten new records of decapod crustaceans from TMV: Gnathophyllum americanum and Thor amboinensis are circumtropical in distribution, whereas Stenopus hispidus, Gnathophylloides mineri and Parribacus antarcticus are disjunct circumtropical species as their distribution in the Atlantic Ocean is limited eastwardly to TMV or Ascension Island (S. hispidus), therefore, do not extending into the eastern Atlantic. Gnathophyllum circellum and Thor manningi are western Atlantic species, with G. circellum previously known only from the Caribbean Sea. Pontonia manningi, Tuleariocaris neglecta and Enoplometopus antillensis are amphi-Atlantic in distribution. Two of the above species are recorded from the southwestern Atlantic for the first time: Gnathophyllum circellum and Tuleariocaris neglecta. These new records corroborate that the marine benthic invertebrate fauna of the TMV archipelago is actually a [...](AU)

O grande isolamento geográfico do jovem arquipélago vulcânico Trindade e Martin Vaz (TMV) suscita questionamentos sobre a origem e os níveis de endemismo de sua fauna. Entretanto, a abordagem destas questões requer o conhecimento abrangente da composição taxonômica da fauna bentônica marinha de TMV. Com o intuito de documentar a biodiversidade em TMV foram efetuadas amostragens da fauna de invertebrados bentônicos durante cinco anos consecutivos do entre-marés até profundidades de 30 m. Nesta oportunidade apresentamos dez novos registros de crustáceos Decapoda para TMV, juntamente com comentários ecológicos e notas zoogeográficas. Gnathophyllum americanum e Thor amboinensis são espécies circumtropicais, enquanto que Stenopus hispidus, Gnathophylloides mineri e Parribacus antarcticus são espécies circumtropicais disjuntas na medida em que sua distribuição no oceano Atlântico encontra-se limitada à leste pelas ilhas TMV ou Ascensão (S. hispidus), consequentemente, não se estendendo ao Atlântico oriental. Gnathophyllum circellum e Thor manningi são espécies do Atlântico ocidental; G. circellum era conhecida previamente apenas do Mar do Caribe. Pontonia manningi, Tuleariocaris neglecta e Enoplometopus antillensis são espécies anfi-Atlânticas. Estes novos registros para TMV corroboram a ideia de que a fauna marinha bentônica de TMV constitui-se em um mosaico de espécies atlântico-ocidentais, atlântico-orientais, centro-atlânticas (insulares), anfi-Atlânticas, endêmicas e circumtropicais. O componente atlântico ocidental tem forte influência na formação faunística de TMV.(AU)

TOWARDS A REVIEW OF THE DECAPOD CRUSTACEA FROM THE REMOTE OCEANIC ARCHIPELAGO OF TRINDADE AND MARTIN VAZ, SOUTH ATLANTIC OCEAN: NEW RECORDS AND NOTES ON ECOLOGY AND ZOOGEOGRAPHY

ABSTRACT The remoteness of the Trindade and Martin Vaz young volcanic archipelago (TMV) raises questions about the source of its marine benthic fauna and levels of endemism. Addressing these questions requires a comprehensive knowledge of the taxonomic composition of the marine fauna of the islands. A five-year survey in the shallow marine waters (up to 30 m) and a literature review on the data published for TMV have been conducted to document the biodiversity of the benthic fauna. Here we report on ten new records of decapod crustaceans from TMV: Gnathophyllum americanum and Thor amboinensis are circumtropical in distribution, whereas Stenopus hispidus, Gnathophylloides mineri and Parribacus antarcticus are disjunct circumtropical species as their distribution in the Atlantic Ocean is limited eastwardly to TMV or Ascension Island (S. hispidus), therefore, do not extending into the eastern Atlantic. Gnathophyllum circellum and Thor manningi are western Atlantic species, with G. circellum previously known only from the Caribbean Sea. Pontonia manningi, Tuleariocaris neglecta and Enoplometopus antillensis are amphi-Atlantic in distribution. Two of the above species are recorded from the southwestern Atlantic for the first time: Gnathophyllum circellum and Tuleariocaris neglecta. These new records corroborate that the marine benthic invertebrate fauna of the TMV archipelago is actually a mosaic of amphi-Atlantic, eastern Atlantic, central Atlantic (insular), endemic and circumtropical species, with a strong western Atlantic component.

RESUMO O grande isolamento geográfico do jovem arquipélago vulcânico Trindade e Martin Vaz (TMV) suscita questionamentos sobre a origem e os níveis de endemismo de sua fauna. Entretanto, a abordagem destas questões requer o conhecimento abrangente da composição taxonômica da fauna bentônica marinha de TMV. Com o intuito de documentar a biodiversidade em TMV foram efetuadas amostragens da fauna de invertebrados bentônicos durante cinco anos consecutivos do entre-marés até profundidades de 30 m. Nesta oportunidade apresentamos dez novos registros de crustáceos Decapoda para TMV, juntamente com comentários ecológicos e notas zoogeográficas. Gnathophyllum americanum e Thor amboinensis são espécies circumtropicais, enquanto que Stenopus hispidus, Gnathophylloides mineri e Parribacus antarcticus são espécies circumtropicais disjuntas na medida em que sua distribuição no oceano Atlântico encontra-se limitada à leste pelas ilhas TMV ou Ascensão (S. hispidus), consequentemente, não se estendendo ao Atlântico oriental. Gnathophyllum circellum e Thor manningi são espécies do Atlântico ocidental; G. circellum era conhecida previamente apenas do Mar do Caribe. Pontonia manningi, Tuleariocaris neglecta e Enoplometopus antillensis são espécies anfi-Atlânticas. Estes novos registros para TMV corroboram a ideia de que a fauna marinha bentônica de TMV constitui-se em um mosaico de espécies atlântico-ocidentais, atlântico-orientais, centro-atlânticas (insulares), anfi-Atlânticas, endêmicas e circumtropicais. O componente atlântico ocidental tem forte influência na formação faunística de TMV.

Biometry of neotropical invertebrates inhabiting floodplain rivers: unraveling bionomy / Biometría de invertebrados de ríos de llanura: desentrañando su bionomía

Currently, it is widely recognized that invertebrates play key roles in neotropical floodplains and in many other environments worldwide. However, little information has been published concerning their biometry, in spite that it represents an essential tool for many different studies. Here, we provided length-mass and length-length relationships by fitting the linearized model (log10 Y = log10a + b log10 X) and several mean biomass ratios ± SE for bivalves, gastropods, quironomids, ephemeropterans, oligochaetes and hirudineans. We measured, weighed, oven dried and incinerated to ashes specimens collected from 2005 to 2014 in the Paraná River, Argentina. The lineal equations had fit levels higher than 75% in most of the significant regressions. Hence, when slopes were compared, differences raised from ontogeny and phylogeny of taxa. Additionally, slopes resulted different from constants of other regions, types of environments and climates. In addition, organic matter ratios resulted significantly different among invertebrates according to their feeding types. The equations and ratios that we provided will facilitate future research on life history, productivity and energy transference in the food webs of invertebrates inhabiting floodplain wetlands and can be used as tools for planning management strategies and in restoration projects of aquatic environments.(AU)

Actualmente, es muy reconocido que los invertebrados tienen un rol clave en los ambientes de llanura aluvial neotropicales así como en otros ambientes alrededor del mundo. Sin embargo, se cuenta con muy poca información publicada en relación con su biometría, a pesar de ser una herramienta esencial para muchos tipos de estudios. En este trabajo se obtuvieron relaciones longitud-masa ajustadas por el modelo linearizado (log10 Y = log10a + b log10X) y diferentes proporciones de materia orgánica promedio ± ES para bivalvos, gastrópodos, quironómidos, efemerópteros, oligoquetos e hirudíneos. Medimos, pesamos, secamos e incineramos hasta cenizas especímenes colectados entre 2005 y 2014 en el río Paraná, Argentina. Las ecuaciones lineales tuvieron valores de ajuste mayores al 75% en la mayoría de las regresiones significativas. Al comparar las pendientes, se encontraron diferencias relacionadas con la ontogenia y filogenia de las taxa. Asimismo, las pendientes resultaron diferentes de las constantes para otras regiones, tipos de ambientes y climas. Asimismo, las proporciones de materia orgánica fueron significativamente diferentes entre invertebrados de acuerdo a su tipo de alimentación. Las ecuaciones y proporciones que obtuvimos facilitarán futuras investigaciones sobre historia de vida, productividad y transferencia de energía en las tramas tróficas de invertebrados en humedales de llanura aluvial y pueden ser empleadas para planificar estrategias de manejo y en proyectos de restauración de ambientes acuáticos.(AU)

Biometry of neotropical invertebrates inhabiting floodplain rivers: unraveling bionomy / Biometría de invertebrados de ríos de llanura: desentrañando su bionomía

Currently, it is widely recognized that invertebrates play key roles in neotropical floodplains and in many other environments worldwide. However, little information has been published concerning their biometry, in spite that it represents an essential tool for many different studies. Here, we provided length-mass and length-length relationships by fitting the linearized model (log10 Y = log10a + b log10 X) and several mean biomass ratios ± SE for bivalves, gastropods, quironomids, ephemeropterans, oligochaetes and hirudineans. We measured, weighed, oven dried and incinerated to ashes specimens collected from 2005 to 2014 in the Paraná River, Argentina. The lineal equations had fit levels higher than 75% in most of the significant regressions. Hence, when slopes were compared, differences raised from ontogeny and phylogeny of taxa. Additionally, slopes resulted different from constants of other regions, types of environments and climates. In addition, organic matter ratios resulted significantly different among invertebrates according to their feeding types. The equations and ratios that we provided will facilitate future research on life history, productivity and energy transference in the food webs of invertebrates inhabiting floodplain wetlands and can be used as tools for planning management strategies and in restoration projects of aquatic environments.

Actualmente, es muy reconocido que los invertebrados tienen un rol clave en los ambientes de llanura aluvial neotropicales así como en otros ambientes alrededor del mundo. Sin embargo, se cuenta con muy poca información publicada en relación con su biometría, a pesar de ser una herramienta esencial para muchos tipos de estudios. En este trabajo se obtuvieron relaciones longitud-masa ajustadas por el modelo linearizado (log10 Y = log10a + b log10X) y diferentes proporciones de materia orgánica promedio ± ES para bivalvos, gastrópodos, quironómidos, efemerópteros, oligoquetos e hirudíneos. Medimos, pesamos, secamos e incineramos hasta cenizas especímenes colectados entre 2005 y 2014 en el río Paraná, Argentina. Las ecuaciones lineales tuvieron valores de ajuste mayores al 75% en la mayoría de las regresiones significativas. Al comparar las pendientes, se encontraron diferencias relacionadas con la ontogenia y filogenia de las taxa. Asimismo, las pendientes resultaron diferentes de las constantes para otras regiones, tipos de ambientes y climas. Asimismo, las proporciones de materia orgánica fueron significativamente diferentes entre invertebrados de acuerdo a su tipo de alimentación. Las ecuaciones y proporciones que obtuvimos facilitarán futuras investigaciones sobre historia de vida, productividad y transferencia de energía en las tramas tróficas de invertebrados en humedales de llanura aluvial y pueden ser empleadas para planificar estrategias de manejo y en proyectos de restauración de ambientes acuáticos.

Biometry of neotropical invertebrates inhabiting floodplain rivers: unraveling bionomy

RESUMEN Actualmente, es muy reconocido que los invertebrados tienen un rol clave en los ambientes de llanura aluvial neotropicales así como en otros ambientes alrededor del mundo. Sin embargo, se cuenta con muy poca información publicada en relación con su biometría, a pesar de ser una herramienta esencial para muchos tipos de estudios. En este trabajo se obtuvieron relaciones longitud-masa ajustadas por el modelo linearizado (log10 Y = log10a + b log10 X) y diferentes proporciones de materia orgánica promedio ± ES para bivalvos, gastrópodos, quironómidos, efemerópteros, oligoquetos e hirudíneos. Medimos, pesamos, secamos e incineramos hasta cenizas especímenes colectados entre 2005 y 2014 en el río Paraná, Argentina. Las ecuaciones lineales tuvieron valores de ajuste mayores al 75% en la mayoría de las regresiones significativas. Al comparar las pendientes, se encontraron diferencias relacionadas con la ontogenia y filogenia de las taxa. Asimismo, las pendientes resultaron diferentes de las constantes para otras regiones, tipos de ambientes y climas. Asimismo, las proporciones de materia orgánica fueron significativamente diferentes entre invertebrados de acuerdo a su tipo de alimentación. Las ecuaciones y proporciones que obtuvimos facilitarán futuras investigaciones sobre historia de vida, productividad y transferencia de energía en las tramas tróficas de invertebrados en humedales de llanura aluvial y pueden ser empleadas para planificar estrategias de manejo y en proyectos de restauración de ambientes acuáticos.

ABSTRACT Currently, it is widely recognized that invertebrates play key roles in neotropical floodplains and in many other environments worldwide. However, little information has been published concerning their biometry, in spite that it represents an essential tool for many different studies. Here, we provided length-mass and length-length relationships by fitting the linearized model (log10 Y = log10a + b log10 X) and several mean biomass ratios ± SE for bivalves, gastropods, quironomids, ephemeropterans, oligochaetes and hirudineans. We measured, weighed, oven dried and incinerated to ashes specimens collected from 2005 to 2014 in the Paraná River, Argentina. The lineal equations had fit levels higher than 75% in most of the significant regressions. Hence, when slopes were compared, differences raised from ontogeny and phylogeny of taxa. Additionally, slopes resulted different from constants of other regions, types of environments and climates. In addition, organic matter ratios resulted significantly different among invertebrates according to their feeding types. The equations and ratios that we provided will facilitate future research on life history, productivity and energy transference in the food webs of invertebrates inhabiting floodplain wetlands and can be used as tools for planning management strategies and in restoration projects of aquatic environments.

First record of Dero (Aulophorus) bimagnasetus Harman (Oligochaeta) from Brazil and habitat characteristics / Primeiro registro de Dero (Aulophorus) bimagnasetus Harman (Oligochaeta) do Brasil e notas ecológicas

Annelid worms represent a significant part of freshwater benthic communities worldwide and Oligochaeta is a particularly species-rich group. Dero (A) bimagnasetus (Naididae) previously found and described from a small marsh in Surinam in 1974, has now been found for the first time in Barra Lake, MG, Brazil. Due to the scarce biological data and absence of ecological information in the literature regarding this species we are presenting morphological information on the specimens obtained and the physical and chemical characteristics of the habitat they were found. This species occurred only in the littoral zone of Barra Lake, in muddy, low oxygen, low conductivity and low organic matter sediment. The four individuals collected ranged 3.17-4.15 mm total length; 0.25 - 0.26 mm body width and 0.16-0.21 mm3 total volume. Considering the present anthropic pressures on freshwater biota and fast biodiversity losses worldwide it is now recognized that attention must be paid to low abundance species and the urgency for preservation of their habitats.(AU)

Vermes anelídeos representam uma parte significativa das comunidades de água doce em todo o mundo e Oligochaeta é um grupo particularmente rico em espécies. Dero (A) bimagnasetus (Naididae) havia sido encontrado e descrito em um pequeno pântano no Suriname em 1974, e agora também coletado na lagoa Barra, MG, Brasil. Devido ao baixo número de espécimes coletados e à ausência de informações ecológicas sobre esta espécie, estamos apresentando informações sobre a morfometria dos espécimes obtidos e as características físicas e químicas de seu habitat. Esta espécie ocorreu apenas na região litorânea da lagoa da Barra, em sedimento lamacento e com pouca matéria orgânica, baixa concentração de oxigênio e baixa condutividade elétrica na água. Os quatro indivíduos encontrados tiveram 3,17-4,15 mm de comprimento total; 0,25-0,26 mm de largura e 0,16-0,21 mm3 de biovolume. Considerando as atuais pressões antrópicas sobre a biota de água doce e as rápidas perdas de biodiversidade em todo o mundo, é agora reconhecido que muita atenção deve ser dada às espécies pouco abundantes e que é urgentemente necessário preservar seus habitats.(AU)

Short-term stability of estuarine benthic assemblages: are storms pattern-defining events?

Storms, associated with strong winds and heavy rains, are often the most severe physical disturbances in shallow coastal areas causing instability to sedimentary environments. We hypothesized herein that if storms influence short-term assemblage structure of macrofauna, then assemblages should change after storms, while remaining relatively stable over calm weather conditions. The study was conducted at the subtropical Paranaguá Bay, in southern Brazil. We selected four 700 m² sites, at the estuarine outlet, to monitor changes in number of species, number of individuals and Shannon diversity. Sampling was arranged considering the weather forecast so that both before and after conditions could be recorded. Data of each site was tested separately to access the significance of specific (before/after) comparisons using t tests. There were no clear effects of storms on macrofaunal species richness, abundance and diversity at the four sampled sites. Conversely, we showed that short-term variation in abundances occurred regardless of weather conditions. Increased dispersal may be the most common process associated with storms instead of mortality. Storms that intermittently affect the southern coast of Brazil can be thus seen as minor driving forces of shallow-water estuarine macrofauna. Effects of extreme meteorological events remain to be assessed.

Short-term stability of estuarine benthic assemblages: are storms pattern-defining events?

Storms, associated with strong winds and heavy rains, are often the most severe physical disturbances in shallow coastal areas causing instability to sedimentary environments. We hypothesized herein that if storms influence short-term assemblage structure of macrofauna, then assemblages should change after storms, while remaining relatively stable over calm weather conditions. The study was conducted at the subtropical Paranaguá Bay, in southern Brazil. We selected four 700 m² sites, at the estuarine outlet, to monitor changes in number of species, number of individuals and Shannon diversity. Sampling was arranged considering the weather forecast so that both before and after conditions could be recorded. Data of each site was tested separately to access the significance of specific (before/after) comparisons using t tests. There were no clear effects of storms on macrofaunal species richness, abundance and diversity at the four sampled sites. Conversely, we showed that short-term variation in abundances occurred regardless of weather conditions. Increased dispersal may be the most common process associated with storms instead of mortality. Storms that intermittently affect the southern coast of Brazil can be thus seen as minor driving forces of shallow-water estuarine macrofauna. Effects of extreme meteorological events remain to be assessed.

Short-term stability of estuarine benthic assemblages: are storms pattern-defining events?

Storms, associated with strong winds and heavy rains, are often the most severe physical disturbances in shallow coastal areas causing instability to sedimentary environments. We hypothesized herein that if storms influence short-term assemblage structure of macrofauna, then assemblages should change after storms, while remaining relatively stable over calm weather conditions. The study was conducted at the subtropical Paranaguá Bay, in southern Brazil. We selected four 700 m² sites, at the estuarine outlet, to monitor changes in number of species, number of individuals and Shannon diversity. Sampling was arranged considering the weather forecast so that both before and after conditions could be recorded. Data of each site was tested separately to access the significance of specific (before/after) comparisons using t tests. There were no clear effects of storms on macrofaunal species richness, abundance and diversity at the four sampled sites. Conversely, we showed that short-term variation in abundances occurred regardless of weather conditions. Increased dispersal may be the most common process associated with storms instead of mortality. Storms that intermittently affect the southern coast of Brazil can be thus seen as minor driving forces of shallow-water estuarine macrofauna. Effects of extreme meteorological events remain to be assessed.

Species composition and abundance of the benthic community of Axiidea and Gebiidea (Crustacea: Decapoda) in the Marapanim Bay, Amazon estuary, northern Brazil

The thalassinideans (Axiidea and Gebiidea) encompasses approximately 615 species with reclusive habits, generally confined to extensive galleries burrowed into the sand or mud and, more rarely, in openings in reefs or the cavities of sessile animals such as sponges and coral. These species use the galleries for shelter, feeding and breeding, except during the pelagic larval stage. They inhabit estuaries, bays, lagoons, beaches, seas and both tropical and temperate oceanic areas throughout the world, distributed predominantly in the intertidal zone (mid-littoral and infralittoral zones). The aim of the present study was to assess the species composition and abundance of thalassinideans, comparing two micro-habitats (consolidated and non-consolidated substrates), and determine whether there is a correlation between abundance of the organisms and time of the year, collection sites or salinity. Twelve monthly samplings were carried out between August 2006 and July 2007 over consolidated and non-consolidated bottoms of the upper and lower portions of the mid-littoral zones, with three sub-samplings, totaling 48 monthly samples and 576 in all. A total of 651 individuals were collected - 114 Lepidophthalmus siriboia Felder & Rodrigues, 1993 and 537 Upogebia vasquezi Ngoc-Ho, 1989. There was correlation between the abundance of both species and salinity, but U. vasquezi was more abundant in the rainy season. Lepidophthalmus siriboia appears to prefer non-consolidated substrates, whereas U. vasquezi prefers consolidated substrates. The recruitment period for the callianassid L. siriboia appears to occur in just two periods of the year and is more intense in the dry season, whereas U. vasquezi is more frequent throughout the year. The smallest and largest sizes (carapace length - CL) recorded for L. siriboia were smaller than those recorded for the species in northeastern region of Brazil. CL values for ovigerous females suggest that U. vasquezi reaches sexual maturity at a smaller size than L. siriboia.

Species composition and abundance of the benthic community of Axiidea and Gebiidea (Crustacea: Decapoda) in the Marapanim Bay, Amazon estuary, northern Brazil

The thalassinideans (Axiidea and Gebiidea) encompasses approximately 615 species with reclusive habits, generally confined to extensive galleries burrowed into the sand or mud and, more rarely, in openings in reefs or the cavities of sessile animals such as sponges and coral. These species use the galleries for shelter, feeding and breeding, except during the pelagic larval stage. They inhabit estuaries, bays, lagoons, beaches, seas and both tropical and temperate oceanic areas throughout the world, distributed predominantly in the intertidal zone (mid-littoral and infralittoral zones). The aim of the present study was to assess the species composition and abundance of thalassinideans, comparing two micro-habitats (consolidated and non-consolidated substrates), and determine whether there is a correlation between abundance of the organisms and time of the year, collection sites or salinity. Twelve monthly samplings were carried out between August 2006 and July 2007 over consolidated and non-consolidated bottoms of the upper and lower portions of the mid-littoral zones, with three sub-samplings, totaling 48 monthly samples and 576 in all. A total of 651 individuals were collected - 114 Lepidophthalmus siriboia Felder & Rodrigues, 1993 and 537 Upogebia vasquezi Ngoc-Ho, 1989. There was correlation between the abundance of both species and salinity, but U. vasquezi was more abundant in the rainy season. Lepidophthalmus siriboia appears to prefer non-consolidated substrates, whereas U. vasquezi prefers consolidated substrates. The recruitment period for the callianassid L. siriboia appears to occur in just two periods of the year and is more intense in the dry season, whereas U. vasquezi is more frequent throughout the year. The smallest and largest sizes (carapace length - CL) recorded for L. siriboia were smaller than those recorded for the species in northeastern region of Brazil. CL values for ovigerous females suggest that U. vasquezi reaches sexual maturity at a smaller size than L. siriboia.

Species composition and abundance of the benthic community of Axiidea and Gebiidea (Crustacea: Decapoda) in the Marapanim Bay, Amazon estuary, northern Brazil

The thalassinideans (Axiidea and Gebiidea) encompasses approximately 615 species with reclusive habits, generally confined to extensive galleries burrowed into the sand or mud and, more rarely, in openings in reefs or the cavities of sessile animals such as sponges and coral. These species use the galleries for shelter, feeding and breeding, except during the pelagic larval stage. They inhabit estuaries, bays, lagoons, beaches, seas and both tropical and temperate oceanic areas throughout the world, distributed predominantly in the intertidal zone (mid-littoral and infralittoral zones). The aim of the present study was to assess the species composition and abundance of thalassinideans, comparing two micro-habitats (consolidated and non-consolidated substrates), and determine whether there is a correlation between abundance of the organisms and time of the year, collection sites or salinity. Twelve monthly samplings were carried out between August 2006 and July 2007 over consolidated and non-consolidated bottoms of the upper and lower portions of the mid-littoral zones, with three sub-samplings, totaling 48 monthly samples and 576 in all. A total of 651 individuals were collected - 114 Lepidophthalmus siriboia Felder & Rodrigues, 1993 and 537 Upogebia vasquezi Ngoc-Ho, 1989. There was correlation between the abundance of both species and salinity, but U. vasquezi was more abundant in the rainy season. Lepidophthalmus siriboia appears to prefer non-consolidated substrates, whereas U. vasquezi prefers consolidated substrates. The recruitment period for the callianassid L. siriboia appears to occur in just two periods of the year and is more intense in the dry season, whereas U. vasquezi is more frequent throughout the year. The smallest and largest sizes (carapace length - CL) recorded for L. siriboia were smaller than those recorded for the species in northeastern region of Brazil. CL values for ovigerous females suggest that U. vasquezi reaches sexual maturity at a smaller size than L. siriboia.

Temporal and spatial variation of rocky shores intertidal benthic communities in Southeast Brazil / Variação espaço-temporal das comunidades bentônicas do entremarés de costões rochosos no Sudeste do Brasil

The relationships between environmental factors and temporal and spatial variations of benthic communities of three rocky shores of the state of Espírito Santo, Southeast Brazil, were studied. Sampling was conducted every three months, from August 2006 to May 2007, using intersection points. Chthamalus bisinuatus (Pilsbry, 1916) (Crustacea) and Brachidontes spp. (Mollusca) were the most abundant taxa, occupying the upper level of the intertidal zone of the rocky shore. The species richness was higher at the lower levels. The invasive species Isognomon bicolor (C. B. Adams, 1845) (Mollusca) occurred at low densities in the studied areas. The clustering analysis dendrogram indicated a separation of communities based on exposed and sheltered areas. According to the variance analyses, the communities were significantly different among the studied areas and seasons. The extent of wave exposure and shore slope influenced the species variability. The Setibão site showed the highest diversity and richness, most likely due to greater wave exposure. The communities showed greater variation in the lower levels where environmental conditions were less severe, relative to the other levels(AU)

Foram realizadas amostragens das comunidades bentônicas de médiolitoral em três costões rochosos do estado do Espírito Santo com o objetivo de estudar a variação espaço-temporal, relacionando com os fatores abióticos. Efetuaram-se coletas trimestrais entre agosto de 2006 e maio de 2007, utilizando o método de pontos de interseção. Chthamalus bisinuatus Pilsbry, 1916 (Crustacea) e Brachidontes spp. (Mollusca) foram os táxons mais abundantes, ocupando os níveis superiores da zona entremarés dos costões. Nas zonas inferiores ocorreu um maior número de espécies. A espécie invasora Isognomon bicolor (C.B. Adams, 1845) (Mollusca) ocorreu em baixa cobertura nas áreas estudadas. O dendrograma indicou a separação das amostras das áreas expostas e abrigadas. Segundo os resultados das análises de variância, as comunidades foram significativamente diferentes entre as áreas e as estações do ano. O grau de exposição às ondas e a inclinação do costão influenciaram a variabilidade de espécies. Setibão apresentou os maiores índices de diversidade e de riqueza, provavelmente devido à maior exposição às ondas. As comunidades apresentaram maiores variações nos níveis inferiores, onde as condições ambientais são menos estressantes em relação aos outros níveis.(AU)

Temporal and spatial variation of rocky shores intertidal benthic communities in Southeast Brazil / Variação espaço-temporal das comunidades bentônicas do entremarés de costões rochosos no Sudeste do Brasil

The relationships between environmental factors and temporal and spatial variations of benthic communities of three rocky shores of the state of Espírito Santo, Southeast Brazil, were studied. Sampling was conducted every three months, from August 2006 to May 2007, using intersection points. Chthamalus bisinuatus (Pilsbry, 1916) (Crustacea) and Brachidontes spp. (Mollusca) were the most abundant taxa, occupying the upper level of the intertidal zone of the rocky shore. The species richness was higher at the lower levels. The invasive species Isognomon bicolor (C. B. Adams, 1845) (Mollusca) occurred at low densities in the studied areas. The clustering analysis dendrogram indicated a separation of communities based on exposed and sheltered areas. According to the variance analyses, the communities were significantly different among the studied areas and seasons. The extent of wave exposure and shore slope influenced the species variability. The Setibão site showed the highest diversity and richness, most likely due to greater wave exposure. The communities showed greater variation in the lower levels where environmental conditions were less severe, relative to the other levels

Foram realizadas amostragens das comunidades bentônicas de médiolitoral em três costões rochosos do estado do Espírito Santo com o objetivo de estudar a variação espaço-temporal, relacionando com os fatores abióticos. Efetuaram-se coletas trimestrais entre agosto de 2006 e maio de 2007, utilizando o método de pontos de interseção. Chthamalus bisinuatus Pilsbry, 1916 (Crustacea) e Brachidontes spp. (Mollusca) foram os táxons mais abundantes, ocupando os níveis superiores da zona entremarés dos costões. Nas zonas inferiores ocorreu um maior número de espécies. A espécie invasora Isognomon bicolor (C.B. Adams, 1845) (Mollusca) ocorreu em baixa cobertura nas áreas estudadas. O dendrograma indicou a separação das amostras das áreas expostas e abrigadas. Segundo os resultados das análises de variância, as comunidades foram significativamente diferentes entre as áreas e as estações do ano. O grau de exposição às ondas e a inclinação do costão influenciaram a variabilidade de espécies. Setibão apresentou os maiores índices de diversidade e de riqueza, provavelmente devido à maior exposição às ondas. As comunidades apresentaram maiores variações nos níveis inferiores, onde as condições ambientais são menos estressantes em relação aos outros níveis.

Chave de identificação de Gastrotricha de águas continentais e marinhas do Brasil

Gastrotricha are free-living microscopic invertebrates, characterized by a meiobenthic life style in freshwater and marine habitats. In spite of the high number of individuals and their ecological importance, this taxon is underestimated in Brazil. Considering the importance of the Gastrotricha in the interstitial benthic community we aimed to help and stimulate new research with this group in Brazil. Thus, the present study provides a taxonomic key for the Brazilian freshwater and marine Gastrotricha based on the available data. Furthermore, we pointed out methods of collecting, preserving and photographing Gastrotricha. Portuguese terminologies of the main morphological characters used to identify species were also listed as a glossary.

Os Gastrotricha são microinvertebrados de vida livre, caracterizados por um estilo de vida meiobentônico em ambientes marinhos e de água doce. Apesar de este grupo ser abundante e ecologicamente importante nas teias alimentares, o seu conhecimento no Brasil é muito subestimado. Com este estudo, considerando a importância dos Gastrotricha nas comunidades bênticas intersticiais, esperamos ajudar e estimular novas pesquisas com este grupo no Brasil. Assim, esse trabalho fornece uma chave dicotômica para todas as espécies previamente reportadas em águas continentais brasileiras. Além disso, apresentamos informações sobre métodos de coleta, técnicas de preservação e de fotografias dos Gastrotricha. As terminologias, em português, das principais características morfológicas utilizadas para distinguir as espécies são apresentas na forma de um glossário.

Chave de identificação de Gastrotricha de águas continentais e marinhas do Brasil

Gastrotricha are free-living microscopic invertebrates, characterized by a meiobenthic life style in freshwater and marine habitats. In spite of the high number of individuals and their ecological importance, this taxon is underestimated in Brazil. Considering the importance of the Gastrotricha in the interstitial benthic community we aimed to help and stimulate new research with this group in Brazil. Thus, the present study provides a taxonomic key for the Brazilian freshwater and marine Gastrotricha based on the available data. Furthermore, we pointed out methods of collecting, preserving and photographing Gastrotricha. Portuguese terminologies of the main morphological characters used to identify species were also listed as a glossary.

Os Gastrotricha são microinvertebrados de vida livre, caracterizados por um estilo de vida meiobentônico em ambientes marinhos e de água doce. Apesar de este grupo ser abundante e ecologicamente importante nas teias alimentares, o seu conhecimento no Brasil é muito subestimado. Com este estudo, considerando a importância dos Gastrotricha nas comunidades bênticas intersticiais, esperamos ajudar e estimular novas pesquisas com este grupo no Brasil. Assim, esse trabalho fornece uma chave dicotômica para todas as espécies previamente reportadas em águas continentais brasileiras. Além disso, apresentamos informações sobre métodos de coleta, técnicas de preservação e de fotografias dos Gastrotricha. As terminologias, em português, das principais características morfológicas utilizadas para distinguir as espécies são apresentas na forma de um glossário.