First record of Salacia tetracythara Lamouroux, 1816 (Hydrozoa, Sertulariidae) as an alien hydroid for the Atlantic Ocean

Abstract We present here the first record of Salacia tetracythara as an alien species for the Atlantic Ocean, specifically the coast of the state of Sergipe, northeast Brazil. The species was found attached to an artificial experimental plate installed in the rainy period (July-October 2017), in an estuarine region of the Sergipe River near the Sergipe Harbour. Salacia tetracythara is characterized by a small triangular space below each hydrotheca and two types of microbasic mastigophore nematocysts that differ in shape, size, and location. The species was described from Australia and has been recorded only for tropical to temperate regions of the Indo-Pacific. Salacia tetracythara seems to be a recent introduction into the Atlantic Ocean and, its introduction probably derived from ship transport between the Sergipe Harbour and regions of Oceania and/or Asia. Further investigation should be conducted to determine whether the species is established in the region and how far inside the estuary it has gone.

On the identity of Porcellana paivacarvalhoi Rodrigues da Costa, 1968 (Crustacea: Anomura: Porcellanidae)

Porcellana paivacarvalhoi Rodrigues da Costa, 1968, described from southeastern Brazil (São Sebastião, São Paulo), is morphologically similar to the eastern Atlantic P. platycheles (Pennant, 1777), and also to the west African P. africana Chace, 1956. The synonymy between P. paivacarvalhoi and P. platycheles was proposed by previous authors without examination of any specimens of P. platycheles, nor did they considered the morphological similarities between P. paivacarvalhoi and P. africana. This synonymy has been implicitly accepted without further analysis. The recent discovery of one male and two females syntypes of P. paivacarvalhoi has prompted new investigations into the status of P. paivacarvalhoi as a junior synonym either of P. platycheles or P. africana. Porcellana paivacarvalhoi is redescribed and illustrated based upon its lectotype herein designated. It is confirmed to be a junior synonym of P. platycheles; all evidence suggests that P. africana is a distinct, separate species. All previous records of P. platycheles from the Brazilian coast are reviewed. Its presence in southeastern Brazil in the late 1960’s most probably represents an historical case of human-mediated introduction by shipping activities. Porcellana platycheles did not manage to establish itself in São Sebastião, nor has it been recorded subsequently elsewhere in Brazil.

On the identity of Porcellana paivacarvalhoi Rodrigues da Costa, 1968 (Crustacea: Anomura: Porcellanidae)

Porcellana paivacarvalhoi Rodrigues da Costa, 1968, described from southeastern Brazil (São Sebastião, São Paulo), is morphologically similar to the eastern Atlantic P. platycheles (Pennant, 1777), and also to the west African P. africana Chace, 1956. The synonymy between P. paivacarvalhoi and P. platycheles was proposed by previous authors without examination of any specimens of P. platycheles, nor did they considered the morphological similarities between P. paivacarvalhoi and P. africana. This synonymy has been implicitly accepted without further analysis. The recent discovery of one male and two females syntypes of P. paivacarvalhoi has prompted new investigations into the status of P. paivacarvalhoi as a junior synonym either of P. platycheles or P. africana. Porcellana paivacarvalhoi is redescribed and illustrated based upon its lectotype herein designated. It is confirmed to be a junior synonym of P. platycheles; all evidence suggests that P. africana is a distinct, separate species. All previous records of P. platycheles from the Brazilian coast are reviewed. Its presence in southeastern Brazil in the late 1960s most probably represents an historical case of human-mediated introduction by shipping activities. Porcellana platycheles did not manage to establish itself in São Sebastião, nor has it been recorded subsequently elsewhere in Brazil.(AU)

Occurrence of non-native fish species in a Neotropical river under the influence of aquaculture activities / Ocorrência de espécies de peixes não nativos em um rio Neotropical sob a influência da atividade aquícola

The introduction of non-native species is one of the greatest global changes and is a substantial threat to continental fish fauna. This study aimed to evaluate the composition and structure of the fish assemblage of the Azul River, a tributary along the left margin of the Piquiri River basin, to determine the occurrence, abundance and spatial distribution of non-native fish species. Sampling was carried out from February to November 2014 at three sites along the river using of electric fishing equipment. Thirty-two fish species belonging to 20 genera, 11 families and five orders were collected. Eight non-native fish species were recorded, and Gymnotus inaequilabiatus and Oreochromis niloticus were listed among the five most abundant species in the Azul River. The fish fauna followed a distribution pattern expected for the Neotropical region, with a predominance of Characiformes and Siluriformes. However, the high representativeness of the abundance of the non-native species of the Gymnotiformes and Perciformes orders highlights the potential negative impacts on the structure of the fish assemblages of the Azul River due to species introductions.(AU)

A introdução de espécies não nativas é uma das grandes mudanças globais e uma das principais ameaças a ictiofauna continental. Dessa forma, esse trabalho teve por objetivo avaliar a composição e estrutura da ictiofauna do rio Azul, um tributário da margem esquerda da bacia do rio Piquiri, a fim de determinar a ocorrência, abundância e distribuição de espécies de peixes não nativas. Para isso, quatro amostragens foram realizadas de fevereiro a novembro de 2014 em três locais ao longo do rio, por meio do uso de equipamento de pesca elétrica. Durante o período amostral, 32 espécies de peixes foram registradas, as quais pertenceram a 20 gêneros, 11 famílias e cinco ordens. Houve o registro de oito espécies de peixes não nativas, dentre elas Gymnotus inaequilabiatus e Oreochromis niloticus estiveram presentes entre as cinco mais abundantes no rio Azul. Desse modo, a ictiofauna do rio Azul seguiu o padrão de distribuição esperado para a região Neotropical, com predominância de Characiformes e Siluriformes. Por outro lado, o aumento de ocorrência de espécies de peixes não nativas, observado da cabeceira para a foz do rio, indica possível processo de homogeneização biótica, potencialmente intensificado pelo escape de peixes não nativos advindos de pisciculturas.(AU)

Occurrence of non-native fish species in a Neotropical river under the influence of aquaculture activities / Ocorrência de espécies de peixes não nativos em um rio Neotropical sob a influência da atividade aquícola

The introduction of non-native species is one of the greatest global changes and is a substantial threat to continental fish fauna. This study aimed to evaluate the composition and structure of the fish assemblage of the Azul River, a tributary along the left margin of the Piquiri River basin, to determine the occurrence, abundance and spatial distribution of non-native fish species. Sampling was carried out from February to November 2014 at three sites along the river using of electric fishing equipment. Thirty-two fish species belonging to 20 genera, 11 families and five orders were collected. Eight non-native fish species were recorded, and Gymnotus inaequilabiatus and Oreochromis niloticus were listed among the five most abundant species in the Azul River. The fish fauna followed a distribution pattern expected for the Neotropical region, with a predominance of Characiformes and Siluriformes. However, the high representativeness of the abundance of the non-native species of the Gymnotiformes and Perciformes orders highlights the potential negative impacts on the structure of the fish assemblages of the Azul River due to species introductions.

A introdução de espécies não nativas é uma das grandes mudanças globais e uma das principais ameaças a ictiofauna continental. Dessa forma, esse trabalho teve por objetivo avaliar a composição e estrutura da ictiofauna do rio Azul, um tributário da margem esquerda da bacia do rio Piquiri, a fim de determinar a ocorrência, abundância e distribuição de espécies de peixes não nativas. Para isso, quatro amostragens foram realizadas de fevereiro a novembro de 2014 em três locais ao longo do rio, por meio do uso de equipamento de pesca elétrica. Durante o período amostral, 32 espécies de peixes foram registradas, as quais pertenceram a 20 gêneros, 11 famílias e cinco ordens. Houve o registro de oito espécies de peixes não nativas, dentre elas Gymnotus inaequilabiatus e Oreochromis niloticus estiveram presentes entre as cinco mais abundantes no rio Azul. Desse modo, a ictiofauna do rio Azul seguiu o padrão de distribuição esperado para a região Neotropical, com predominância de Characiformes e Siluriformes. Por outro lado, o aumento de ocorrência de espécies de peixes não nativas, observado da cabeceira para a foz do rio, indica possível processo de homogeneização biótica, potencialmente intensificado pelo escape de peixes não nativos advindos de pisciculturas.

Physiological response of invasive mussel Limnoperna fortunei (Dunker, 1857) (Bivalvia: Mytilidae) submitted to transport and experimental conditions / Resposta fisiológica do mexilhão invasor Limnoperna fortunei (Dunker, 1857) (Bilvalvia: Mytilidae) submetido ao transporte e condições experimentais

Successful animal rearing under laboratory conditions for commercial processes or laboratory experiments is a complex chain that includes several stressors (e.g., sampling and transport) and incurs, as a consequence, the reduction of natural animal conditions, economic losses and inconsistent and unreliable biological results. Since the invasion of the bivalve Limnoperna fortunei (Dunker, 1857) in South America, several studies have been performed to help control and manage this fouling pest in industrial plants that use raw water. Relatively little attention has been given to the laboratory rearing procedure of L. fortunei, its condition when exposed to a stressor or its acclimation into laboratory conditions. Considering this issue, the aims of this study are to (i) investigate L. fortunei physiological responses when submitted to the depuration process and subsequent air transport (without water/dry condition) at two temperatures, based on glycogen concentrations, and (ii) monitor the glycogen concentrations in different groups when maintained for 28 days under laboratory conditions. Based on the obtained results, depuration did not affect either of the groups when they were submitted to approximately eight hours of transport. The variation in glycogen concentration among the specimens that were obtained from the field under depurated and non-depurated conditions was significant only in the first week of laboratory growth for the non-depurated group and in the second week for the depurated group. In addition, the tested temperature did not affect either of the groups that were submitted to transport. The glycogen concentrations were similar to those of the specimens that were obtained from the field in third week, which suggests that the specimens acclimated to laboratory conditions during this period of time. Thus, the results indicate that the air transport and acclimation time can be successfully incorporated into experimental studies of L. fortunei[...](AU)

A criação bem sucedida de animais em condições de laboratório para processos comerciais ou experimentais é uma cadeia complexa que inclui vários fatores de estresse (ex. coleta e transporte) que tem como consequência a redução das condições naturais do animal, prejuízos econômicos e resultados biológicos inconsistentes. Desde a invasão do bivalve Limnoperna fortunei (Dunker, 1857) na América do Sul, vários estudos têm sido realizados para ajudar no controle e gestão dessa praga em plantas industriais que utilizam água. Relativamente pouca atenção tem sido dada ao processo de criação de L. fortunei em laboratório, sua condição quando exposta ao estresse e sua aclimatação a condições de laboratório. Considerando estes aspectos, os objetivos deste estudo foram: (i) investigar as respostas fisiológicas de L. fortunei submetidos ao processo de depuração e subsequente transporte (sem água/condição seca) em duas temperaturas, analisando as diferentes concentrações de glicogênio e (ii) monitorar as concentrações de glicogênio nos diferentes grupos, quando mantidos por 28 dias em condições de laboratório. Com base nos resultados obtidos, a depuração não afetou nenhum grupo quando eles foram submetidos a oito horas de transporte. A variação da concentração de glicogênio entre os espécimes do campo quando depurados e não depurados, foi significativa apenas em relação à primeira semana em laboratório para o grupo não depurado e à segunda semana para o grupo depurado. Além disto, a temperatura testada não afetou os grupos submetidos ao transporte. As concentrações de glicogénio foram semelhantes as dos espécimes do campo a partir da terceira semana, o que sugere que os espécimes estão aclimatados às condições de laboratoriais neste período de tempo. Assim, os resultados indicam que o transporte ao ar e o tempo de aclimatação podem ser incorporados com sucesso aos estudos experimentais com L. fortunei[...](AU)

Record of Nile tilapia in the Mandira river, Cananéia, São Paulo state / Registro da tilápia-do-nilo no rio Mandira, Cananéia, estado de São Paulo

The present short communication reports the occurrence of Nile Tilapia (Oreochromis niloticus) in the Mandira River, in the extractive reserve in the Cananéia estuary, São Paulo State. In May 2014, using dip nets, we collected five specimens of O. niloticus in the estuary, with length ranging from 1.4 to 2.5 cm and weight between 0.8 and 2.3 g. Samplings performed in July indicated the presence of additional four specimens of O. niloticus in other stretches of the same river. The occurrence of alien species in conservation areas has high ecological importance, as they can cause environmental and biodiversity alterations; in Brazil, the introduction of alien species is usually related to economic activities, such as the Nile tilapia aquaculture.(AU)

A presente nota registra a ocorrência de tilápia-do-nilo (Oreochromis niloticus) na Reserva Extrativista do Rio Mandira, localizada no munícipio de Cananéia, São Paulo. Em maio de 2014, foram coletados por meio de puçás, cinco exemplares de O. niloticus no estuário, com comprimentos variando entre 1,5 a 2,5 cm e peso entre 0,8 e 2,3 g. Coletas realizadas em julho evidenciaram a presença de mais quatro espécimes de O. niloticus em outros trechos do rio estudado. A ocorrência de espécies exóticas em unidades de conservação é de extrema relevância ecológica, uma vez que pode modificar o ambiente e a biodiversidade de uma região, sendo que no Brasil, a introdução de espécies exóticas encontra-se tipicamente vinculada às atividades de interesse socioeconômico, como é o caso do cultivo de tilápia-do-nilo.(AU)

Record of Nile tilapia in the Mandira river, Cananéia, São Paulo state / Registro da tilápia-do-nilo no rio Mandira, Cananéia, estado de São Paulo

The present short communication reports the occurrence of Nile Tilapia (Oreochromis niloticus) in the Mandira River, in the extractive reserve in the Cananéia estuary, São Paulo State. In May 2014, using dip nets, we collected five specimens of O. niloticus in the estuary, with length ranging from 1.4 to 2.5 cm and weight between 0.8 and 2.3 g. Samplings performed in July indicated the presence of additional four specimens of O. niloticus in other stretches of the same river. The occurrence of alien species in conservation areas has high ecological importance, as they can cause environmental and biodiversity alterations; in Brazil, the introduction of alien species is usually related to economic activities, such as the Nile tilapia aquaculture.

A presente nota registra a ocorrência de tilápia-do-nilo (Oreochromis niloticus) na Reserva Extrativista do Rio Mandira, localizada no munícipio de Cananéia, São Paulo. Em maio de 2014, foram coletados por meio de puçás, cinco exemplares de O. niloticus no estuário, com comprimentos variando entre 1,5 a 2,5 cm e peso entre 0,8 e 2,3 g. Coletas realizadas em julho evidenciaram a presença de mais quatro espécimes de O. niloticus em outros trechos do rio estudado. A ocorrência de espécies exóticas em unidades de conservação é de extrema relevância ecológica, uma vez que pode modificar o ambiente e a biodiversidade de uma região, sendo que no Brasil, a introdução de espécies exóticas encontra-se tipicamente vinculada às atividades de interesse socioeconômico, como é o caso do cultivo de tilápia-do-nilo.

Invading the natural marine substrates: a case study with invertebrates in South Brazil

The number of biological invasions has grown dramatically in recent decades, as well as the world's human population and coastal development. Anthropogenic habitats, such as pier pilings and break waters, have been constantly added to marine environment, usually concentrated in estuarine areas. These habitats are focal points for marine invasions, but relatively little is known about the spread of non-indigenous species (NIS) to nearby natural habitats. This study aimed to determine the extent to which NIS have spread to natural substrates both inside estuarine areas and in the adjacent open sea. We conducted a field survey and a literature review, which have been critically discussed and validated. The updated NIS list of benthic invertebrates comprises 19 species: Ascidiacea (5), Cirripedia (5), Cnidaria (3), Mollusca (3), Polychaeta (1), Decapoda (1), and Echinodermata (1). Our results suggested substantial spread of non-indigenous species into natural substrates. Altogether, 18 and 16 NIS were recorded in artificial and natural substrata, both representing 13% of the total species in each habitat. The percentage of NIS was more pronounced in the estuarine areas, 17.6% in artificial habitats and 18.6% in natural ones. Programs developed for the monitoring of marine invasion have to broaden their focus including natural areas adjacent to ports and marinas, to follow the spread and impact of NIS on these areas.

Invading the natural marine substrates: a case study with invertebrates in South Brazil

The number of biological invasions has grown dramatically in recent decades, as well as the world's human population and coastal development. Anthropogenic habitats, such as pier pilings and break waters, have been constantly added to marine environment, usually concentrated in estuarine areas. These habitats are focal points for marine invasions, but relatively little is known about the spread of non-indigenous species (NIS) to nearby natural habitats. This study aimed to determine the extent to which NIS have spread to natural substrates both inside estuarine areas and in the adjacent open sea. We conducted a field survey and a literature review, which have been critically discussed and validated. The updated NIS list of benthic invertebrates comprises 19 species: Ascidiacea (5), Cirripedia (5), Cnidaria (3), Mollusca (3), Polychaeta (1), Decapoda (1), and Echinodermata (1). Our results suggested substantial spread of non-indigenous species into natural substrates. Altogether, 18 and 16 NIS were recorded in artificial and natural substrata, both representing 13% of the total species in each habitat. The percentage of NIS was more pronounced in the estuarine areas, 17.6% in artificial habitats and 18.6% in natural ones. Programs developed for the monitoring of marine invasion have to broaden their focus including natural areas adjacent to ports and marinas, to follow the spread and impact of NIS on these areas.(AU)

The non-indigenous bryozoan Triphyllozoon (Cheilostomata: Phidoloporidae) in the Atlantic: morphology and dispersion on the Brazilian coast

Bryozoans constitute an important component of marine-fouling communities of anthropogenic substrata. Many species have been reported as exotic or widespread around the world, typically in ports and harbors of non-polar regions. Here we present the first record of a species of the bryozoan Triphyllozoon in the Atlantic Ocean. Triphyllozoon arcuatum (MacGillivray, 1889), described originally from Australia, is reported herein from natural substrata in Singapore and natural and artificial substrata in Brazil. Although easily recognizable, the species has not been previously reported from anywhere else in the Atlantic. In the latter instance, the species was collected during monitoring of the invasive scleractinian corals Tubastraea spp. on an oil platform originally from Singapore and now located at Todos os Santos Bay, northeastern Brazil. Colonies of T. arcuatum were also found associated with three species of sponges, giving evidence that it is also growing in the natural environment. Todos os Santos Bay is characterized by intense commercial shipping traffic and oil exploration and the finding of T. arcuatum on an oil platform provides strong evidence that it represents a non-indigenous species in the Atlantic. Owing to the possible impact of T. arcuatum in Brazil, further studies and monitoring of its bioinvasion are recommended.

The non-indigenous bryozoan Triphyllozoon (Cheilostomata: Phidoloporidae) in the Atlantic: morphology and dispersion on the Brazilian coast

Bryozoans constitute an important component of marine-fouling communities of anthropogenic substrata. Many species have been reported as exotic or widespread around the world, typically in ports and harbors of non-polar regions. Here we present the first record of a species of the bryozoan Triphyllozoon in the Atlantic Ocean. Triphyllozoon arcuatum (MacGillivray, 1889), described originally from Australia, is reported herein from natural substrata in Singapore and natural and artificial substrata in Brazil. Although easily recognizable, the species has not been previously reported from anywhere else in the Atlantic. In the latter instance, the species was collected during monitoring of the invasive scleractinian corals Tubastraea spp. on an oil platform originally from Singapore and now located at Todos os Santos Bay, northeastern Brazil. Colonies of T. arcuatum were also found associated with three species of sponges, giving evidence that it is also growing in the natural environment. Todos os Santos Bay is characterized by intense commercial shipping traffic and oil exploration and the finding of T. arcuatum on an oil platform provides strong evidence that it represents a non-indigenous species in the Atlantic. Owing to the possible impact of T. arcuatum in Brazil, further studies and monitoring of its bioinvasion are recommended.(AU)

First record of Ceratium furcoides (Dinophyta), an invasive species, in a temporary high-altitude lake in the Iron Quadrangle (MG, Southeast Brazil) / Primeiro registro de Ceratium furcoides (Dinophyta), uma espécie invasora, em um lago temporário de alta altitude no Quadrilátero Ferrífero (MG, Sudeste do Brasil)

Dinoflagellates of the genus Ceratium are generally marine organisms, but rare occurrences in freshwater have been observed in Brazil. In this paper we are recording for the first time the presence of Ceratium furcoides, an invasive species, in a shallow, natural intermittent pool formed at a high-altitude at the southern end of the Iron Quadrangle, an iron-mining district of Minas Gerais State (Southeast Brazil). Samples were collected in October and November of 2010 (rainy period). The population density of this organism observed in Lagoa Seca (“Dry Pool”) was very low, at most 4 ind L–1. Mountain lakes are extremely vulnerable to atmospheric deposition of organisms, making them valuable witnesses both of the many forms of impact arising from human activities and of the extended global connections that facilitate the dispersion and introduction of new species over great distances. Studies on the population dynamics of C. furcoides in natural tropical systems are still rare and very recent to the brazilian scenario and hence the monitoring of its dynamics and the potential impact on aquatic communities of its becoming established are essential to an understanding of the process of bioinvasion by this species.(AU)

Dinoflagelados do gênero Ceratium são principalmente marinhos, porém existem raras ocorrências em água doce no Brasil. Neste estudo registramos pela primeira vez a ocorrência de Ceratium furcoides, uma espécie invasora em um lago altitudinal natural raso localizado na porção sul do Quadrilátero Ferrífero, uma área de extração mineral no estado de Minas Gerais. As coletas foram realizadas nos meses de outubro e novembro de 2010 (período chuvoso). As densidades observadas para C. furcoides na Lagoa Seca foram muito baixas, com máximo de 4 ind L–1. Lagos de altitude são altamente vulneráveis à deposição atmosférica, o que os torna importantes testemunhos não só dos múltiplos impactos derivados de atividades humanas, mas também das extensas conexões globais, que acabam por facilitar a dispersão e introdução de espécies. Estudos sobre a dinâmica de C. furcoides em sistemas tropicais naturais ainda são escassos e por isso, o monitoramento de sua dinâmica e dos impactos potenciais em comunidades aquáticas a partir do seu estabelecimento, torna-se fundamental para o entendimento dos processos relacionados à bioinvasão desta espécie.(AU)

First record of Amphipoda Talitroides topitotum (Burt, 1934) (Gammaridea, Talitridae) in the State of Espírito Santo, Brazil / Primeiro registro do Amphipoda Talitroides topitotum (Burt, 1934) (Gammaridea, Talitridae) no Estado do Espírito Santo, Brasil

Talitroides topitotum (Amphipoda) was introduced in Brazil by silviculture activities. Currently the species is distributed in the states of Paraná, Rio de Janeiro and São Paulo. This paper describes the species occurrence in the state of Espírito Santo. The objective of this study was to determine the interference of the edge effect on community structure of macroinvertebrates associated with leaf litter, where a T. topitotum female specimen was observed in coffee cultivations in March 2008.(AU)

Talitroides topitotum (Amphipoda) foi introduzido no Brasil pelas atividades de silvicultura. Atualmente a espécie está distribuída nos Estados do Paraná, Rio de Janeiro e São Paulo. Este trabalho descreve a ocorrência desta espécie no Estado do Espírito Santo. O objetivo deste estudo foi determinar a interferência do efeito de borda na estruturada comunidade de macroinvertebrados associados ao folhiço, onde um espécime fêmea de T. topitotum foi observado em cultivo de café em março de 2008.(AU)

Invasion process of Limnoperna fortunei (Bivalvia: Mytilidae): the case of Uruguay River and emissaries of the Esteros del Iberá Wetland, Argentina

Limnoperna fortunei (Dunker, 1857), during its invasion process in South America, has caused severe impacts both on natural environments altering native biodiversity, ecosystem structure and function-, and on man-made structures causing economic looses. Twenty-one samples were taken from the right bank of the Uruguay River, from tributaries of the Uruguay and Paraná Rivers, the drainage of the Esteros del Ibera Wetland. Based on this fieldwork, the presence of larvae and adults of L. fortunei was determined. Also, through the comparison of environmental characteristic with the known tolerance limits for the species, the possibility of its establishment in environments not yet invaded was determined. Most of the sampling stations have features that allow the development of stable populations L. fortunei, including the rivers that drain the Esteros del Ibera, allowing access of this invasive species to this important wetland.

Detection of introduced sessile species on the near shore continental shelf in southern Brazil

Invasion by marine species, often considered a grave threat to marine ecosystems, occurs throughout the world as a consequence of many anthropogenic activities. In coastal Paraná, many factors including shipping, aquaculture and the use of artificial substrates provide suitable environments for the establishment and rapid spread of introduced marine species. To better understand this process, the encrusting community was studied on polyethylene plates (n = 120, 10 x 10 cm) that were placed seasonally at fixed locations on the inner continental shelf to detect non-native species. Of the 62 taxa found, 40 were identified to species, 14 of which were native, 9 introduced and 17 cryptogenic. We found a new introduction while most introduced species were previously reported at a nearby estuary with an international port. Possible complementary explanations for these detections are 1) estuaries influence ecological processes on the inner continental shelf, 2) the study area is near the route of cargo and other ships entering the port, 3) other local vectors, such as hulls of fishing and recreational boats, and artificial reefs link the estuary to the offshore areas. Thus, not only are estuaries invaded by exotic species, but also non-indigenous marine species may be present in the open sea where they are likely to colonize artificial substrates.

Detection of introduced sessile species on the near shore continental shelf in southern Brazil

Invasion by marine species, often considered a grave threat to marine ecosystems, occurs throughout the world as a consequence of many anthropogenic activities. In coastal Paraná, many factors including shipping, aquaculture and the use of artificial substrates provide suitable environments for the establishment and rapid spread of introduced marine species. To better understand this process, the encrusting community was studied on polyethylene plates (n = 120, 10 x 10 cm) that were placed seasonally at fixed locations on the inner continental shelf to detect non-native species. Of the 62 taxa found, 40 were identified to species, 14 of which were native, 9 introduced and 17 cryptogenic. We found a new introduction while most introduced species were previously reported at a nearby estuary with an international port. Possible complementary explanations for these detections are 1) estuaries influence ecological processes on the inner continental shelf, 2) the study area is near the route of cargo and other ships entering the port, 3) other local vectors, such as hulls of fishing and recreational boats, and artificial reefs link the estuary to the offshore areas. Thus, not only are estuaries invaded by exotic species, but also non-indigenous marine species may be present in the open sea where they are likely to colonize artificial substrates.

Invasion process of Limnoperna fortunei (Bivalvia: Mytilidae): the case of Uruguay River and emissaries of the Esteros del Iberá Wetland, Argentina

Limnoperna fortunei (Dunker, 1857), during its invasion process in South America, has caused severe impacts both on natural environments altering native biodiversity, ecosystem structure and function-, and on man-made structures causing economic looses. Twenty-one samples were taken from the right bank of the Uruguay River, from tributaries of the Uruguay and Paraná Rivers, the drainage of the Esteros del Ibera Wetland. Based on this fieldwork, the presence of larvae and adults of L. fortunei was determined. Also, through the comparison of environmental characteristic with the known tolerance limits for the species, the possibility of its establishment in environments not yet invaded was determined. Most of the sampling stations have features that allow the development of stable populations L. fortunei, including the rivers that drain the Esteros del Ibera, allowing access of this invasive species to this important wetland.

Invasion process of Limnoperna fortunei (Bivalvia: Mytilidae): the case of Uruguay River and emissaries of the Esteros del Iberá Wetland, Argentina

Limnoperna fortunei (Dunker, 1857), during its invasion process in South America, has caused severe impacts both on natural environments altering native biodiversity, ecosystem structure and function-, and on man-made structures causing economic looses. Twenty-one samples were taken from the right bank of the Uruguay River, from tributaries of the Uruguay and Paraná Rivers, the drainage of the Esteros del Ibera Wetland. Based on this fieldwork, the presence of larvae and adults of L. fortunei was determined. Also, through the comparison of environmental characteristic with the known tolerance limits for the species, the possibility of its establishment in environments not yet invaded was determined. Most of the sampling stations have features that allow the development of stable populations L. fortunei, including the rivers that drain the Esteros del Ibera, allowing access of this invasive species to this important wetland.

Detection of introduced sessile species on the near shore continental shelf in southern Brazil

Invasion by marine species, often considered a grave threat to marine ecosystems, occurs throughout the world as a consequence of many anthropogenic activities. In coastal Paraná, many factors including shipping, aquaculture and the use of artificial substrates provide suitable environments for the establishment and rapid spread of introduced marine species. To better understand this process, the encrusting community was studied on polyethylene plates (n = 120, 10 x 10 cm) that were placed seasonally at fixed locations on the inner continental shelf to detect non-native species. Of the 62 taxa found, 40 were identified to species, 14 of which were native, 9 introduced and 17 cryptogenic. We found a new introduction while most introduced species were previously reported at a nearby estuary with an international port. Possible complementary explanations for these detections are 1) estuaries influence ecological processes on the inner continental shelf, 2) the study area is near the route of cargo and other ships entering the port, 3) other local vectors, such as hulls of fishing and recreational boats, and artificial reefs link the estuary to the offshore areas. Thus, not only are estuaries invaded by exotic species, but also non-indigenous marine species may be present in the open sea where they are likely to colonize artificial substrates.