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Over the past few decades, corals of the genus Tubastraea have spread globally, revealing themselves to be organisms of great invasive capacity. Their constant expansion on the Brazilian coast highlights the need for studies to monitor the invasion process. The growth, fecundity, settlement, and data on the coverage area of three co-occurring Tubastraea species in the 2015-2016 period were related to temperature variation and light irradiance on the rocky shores of Arraial do Cabo, Rio de Janeiro. Hence, this study sought to understand and compare the current invasion scenario and characteristics of the life history strategy of sun coral species based on environmental variables, considering the uniqueness of this upwelling area in the southwestern Atlantic. For that, we evaluate the fecundity, settlement, and growth rates of corals by carrying out comparative studies between species over time and correlating them with the variables temperature and irradiance, according to seasonality. Field growth of colonies was measured every two months during a sample year. Monthly collections were performed to count reproductive oocytes to assess fecundity. Also, quadrats were scrapped from an area near a large patch of sun coral to count newly attached coral larvae and used years later to assess diversity and percentage coverage. Results showed that corals presented greater growth during periods of high thermal amplitude and in months with below-average temperatures. Only Tubastraea sp. had greater growth and polyp increase in areas with higher light incidence, showing a greater increase in total area compared to all the other species analyzed. Despite the observed affinity with high temperatures, settlement rates were also higher during the same periods. Months with low thermal amplitude and higher temperature averages presented high fecundity. While higher water temperature averages showed an affinity with greater coral reproductive activity, growth has been shown to be inversely proportional to reproduction. Our study recorded the most significant coral growth for the region, an increase in niche, high annual reproductive activity, and large area coverage, showing the ongoing adaptation of the invasion process in the region. However, lower temperatures in the region affect these corals' reproductive activity and growth, slowing down the process of introduction into the region. To better understand the advantages of these invasion strategies in the environment, we must understand the relationships between them and the local community that may be acting to slow down this colonization process.

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The genetic characteristics of invasive species have a significant impact on their ability to establish and spread. The blue mussel (Mytilus galloprovincialis), native to the Mediterranean Sea, is a leading invasive species of intertidal coasts throughout much of the world. Here, we used mitochondrial DNA sequence data to investigate the genetic diversity and phylogeographic structure of invasive (M. galloprovincialis) versus native (Mytilus chilensis) populations of blue mussels in Chile. We evaluated whether genetic diversity in invasive populations could be explained by the genetic characteristics of the native sources from which they might be derived. A phylogenetic analysis confirmed two lineages of the invasive M. galloprovincialis, i.e., the NW Atlantic and the Mediterranean lineages. We found no evidence of genetic structure in the invasive range of M. galloprovincialis in Chile, most probably because of its recent arrival. We did, however, detect a spatial mixture of both M. galloprovincialis lineages at sampling locations along the Chilean coast, giving rise to higher levels of genetic diversity in some areas compared to the population of native M. chilensis. The coastal area of the invasion is still small in extent (~100 km on either side of two large ports), which supports the hypothesis of a recent introduction. Further expansion of the distribution range of M. galloprovincialis may be limited to the north by increasing water temperatures and to the south by a natural biogeographic break that may slow or perhaps stop its spread. The use of internal borders as a tool to minimise or prevent M. galloprovincialis spread is therefore a genuine management option in Chile but needs to be implemented rapidly.

RESUMO

Recent arrivals of tar balls have been observed in several tropical beaches associated with the oceanic circulation that flows to the Brazilian continental shelf. Between August and September 2022, tar balls were collected in the northeastern coast of Brazil and analyzed. Nearly 90 % of the oils were colonized by barnacles, polychaetes, decapods, and algae. Most rafting organisms were Lepas anserifera with capitulum measuring 0.32 to 22.21 mm. Based on the growth rate of barnacles and the speed of the SEC it was estimated that tar balls were floating since July and August 2022 and traveled a maximum of 1938.82 km. The organisms and tar balls' possible origin is in the international waters, near to the meso-Atlantic ridge, known for oil tanker traffic. The tar balls, in addition to the oil-related impacts, can act as a vector of long-distance species dispersion, and it needs to raise an alert, considering the possible ecological impacts.

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Bryozoans are commonly associated with various artificial structures in marine environments and have been responsible for several bioinvasion events worldwide. Understanding the interactions between bryozoans and artificial structures is therefore essential to prevent the establishment and spread of potential bioinvaders. This study investigated bryozoan recruitment on four different substrates (PET, nautical ropes, metal, and PVC) placed in three orientations (vertical, horizontal facing down and facing up) in an area of the Western Atlantic. In total, 15 species of bryozoans were found. The results revealed significant variations in assemblages' richness, with bryozoans showing a preference for settling on PVC (14 species found) and on the underside of horizontal substrates (15 species found), resulting in the higher representativity observed in this study. Cryptogenic (nine species) and exotic (five species) bryozoans dominated the assemblages in all treatments, indicating that the type of substrate (especially artificial) and its orientation can favor the settlement of bryozoans, particularly non-native species. Therefore, the availability of multiple types of artificial substrates in marine environments should be treated as a cause for concern.

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Non-indigenous species tend to colonize aquaculture installations, especially when they are near international ports. In addition to the local environmental hazard that colonizing non-indigenous species pose, they can also take advantage of local transport opportunities to spread elsewhere. In this study, we examined the risk of the spread of eight invasive fouling species that are found in mussel farms in southern Brazil. We used ensemble niche models based on worldwide occurrences of these species, and environmental variables (ocean temperature and salinity) to predict suitable areas for each species with three algorithms (Maxent, Random Forest, and Support Vector Machine). As a proxy for propagule pressure, we used the tonnage transported by container ships from Santa Catarina (the main mariculture region) that travel to other Brazilian ports. We found that ports in the tropical states of Pernambuco, Ceará, and Bahia received the largest tonnage, although far from Santa Catarina and in a different ecoregion. The ascidians Aplidium accarense and Didemnum perlucidum are known from Bahia, with a high risk of invasion in the other states. The bryozoan Watersipora subtorquata also has a high risk of establishment in Pernambuco, while the ascidian Botrylloides giganteus has a medium risk in Bahia. Paraná, a state in the same ecoregion as Santa Catarina is likely to be invaded by all species. A second state in this region, Rio Grande do Sul, is vulnerable to A. accarense, the barnacle Megabalanus coccopoma, and the mussel Mytilus galloprovincialis. Climate change is changing species latitudinal distributions and most species will gain rather than lose area in near future (by 2050). As an ideal habitat for fouling organisms and invasive species, aquaculture farms can increase propagule pressure and thus the probability that species will expand their distributions, especially if they are close to ports. Therefore, an integrated approach of the risks of both aquaculture and nautical transport equipment present in a region is necessary to better inform decision-making procedures aiming at the expansion or establishment of new aquaculture farms. The risk maps provided will allow authorities and regional stakeholders to prioritize areas of concern for mitigating the present and future spread of fouling species.

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Sponges-associated microorganisms play important roles in their health and ecology; consequently, they may be crucial in the successful adaptation of exotic species to novel environments. However, few studies have focused on the microbial diversity of exotic sponges, especially those with calcium carbonate spicules (class Calcarea). Therefore, this is the first in situ characterization of the microbiota of the exotic calcareous sponges Sycettusa hastifera and Paraleucilla magna. Our results suggest that S. hastifera has a more stable microbiota than P. magna, as there were no differences in its beta diversity among sampling sites. Conversely, P. magna showed significant differences in its microbial communities, perhaps related to its adhesion to artificial substrate and/or shellfish mariculture activities. Each sponge species presented a single dominant proteobacterial OTU potentially active in the nitrogen cycle, which could help sponge detoxification, especially in polluted areas where exotic species usually establish. Our results show the importance of assessing the microbial diversity to unveil host-microorganism relationships and suggest that these associated nitrogen-cycling microorganisms could favor the success of exotic sponges in new environments.

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Species invasion is a major threat to marine biodiversity and function; thus, studying the effects of recently reported exotic species is extremely important. Several soft coral species (Alcyonacea) have invaded the Atlantic Ocean but their effects are poorly known. Here, we investigated the effects of the invasive species Sarcothelia sp. (Alcyonacea, Xeniidae) on native benthic shallow reef communities in Brazil. We hypothesized that increasing Sarcothelia sp. abundance would be related to species richness decreases and native community structure changes. Multivariate analysis showed significant dissimilarity between invaded (high Sarcothelia sp. abundance) and non-invaded areas (high abundance of the octocoral Neospongodes atlantica and zoantharians). The invaded area showed less species composition variability (i.e., homogenization) than non-invaded ones. Within the invaded area we observed that Sarcothelia sp. abundance reduced species richness. The lowest native benthic richness (10 taxa) was observed in a transect with the highest invader cover, while the transect with the lowest Sarcothelia sp. cover presented 26 native taxa. These findings are likely related to the invasive novel functional traits, i.e., invader growth form and allelochemicals. A clear inverse abundance pattern between invasive Sarcothelia sp. and N. atlantica, indicated an intense competition between octocorals. Our study showed remarkable evidence of negative impacts of invasive soft corals on reef biodiversity. There is an urgent need for experiments evaluating changes in different ecological processes and to implement management actions.

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Kellicottia bostoniensis (Rousselet, 1908) es un rotífero planctónico, nativo de Norte América, pero reportado en Europa, Asia y hasta el momento en Sudamérica en Brasil y Argentina, donde ha sido señalado como especie invasora. En muestreos de zooplancton realizados en la zona fótica de diferentes ecosistemas colombianos (humedales urbanos, embalses y ríos) entre el 2019 y el 2022 se registraron individuos de K. bostoniensis. Este trabajo representa el primer reporte para Colombia y el norte de Sudamérica expandiendo su rango de distribución en el continente. Los especímenes analizados muestran las características morfológicas y morfométricas típicas de la especie K. bostoniensis y una distribución en un amplio rango de condiciones ambientales, como ha sido reportado en otras regiones. Se evidencia su potencial invasor y la posibilidad de que su rango de distribución se expanda hacia otras cuencas y ecosistemas colombianos, así como otros países de Sur América.

Kellicottia bostoniensis (Rousselet, 1908) is a planktonic rotifer, native from North America, but reported in Europe, Asia and South American countries such as Brazil and Argentina, where is registered as invasive species. In zooplankton sampling carried out in the photic zone of different Colombian ecosystems (urban wetlands, reservoirs and rivers) between 2019 and 2022, individuals belonging to this species were recorded. This work is the first report in both Colombia and the North of South America, expanding its distribution range in the continent. The analyzed specimens show the typical morphological and morphometric characteristics of the K. bostoniensis species and a distribution in a wide range of environmental conditions, as it has been reported in other regions. Its invasive potential is evidenced and the possibility that its distribution range expands towards other basins and ecosystems in Colombia and other countries of South America.

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La presente comunicación proporciona información de la presencia en Perú de dos especies invasoras del género Ceratium: C. hirundinella (O.F. Müller) Dujardin y C. furcoides (Levander) Langhans. Se brinda información sobre la distribución de ambas especies en cuerpos de agua peruanos, así como datos de sus abundancias.

This works provides information on the presence in Peru of two invasive species of the genus Ceratium: C. hirundinella (O.F. Müller) Dujardin and C. furcoides (Levander) Langhans. Information is provided on the distribution of both species in Peruvian water bodies, as well as data on their abundance.

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Citizen science is an excellent tool in studies of the spatial distribution of non-native species. In Brazil, Opsanus beta has recently been introduced. Studies indicate the occurrence of this species in five estuaries off the Brazilian coast (Guanabara Bay, Sepetiba Bay, Santos Bay, Paranaguá Estuarine Complex and Guaratuba Bay). The present study aims to understand the dispersion of this species on the Brazilian coast through citizen science. Between January and May 2021, information about O. beta was weekly posted in 32 recreational fishing Facebook groups. Sixty-five fishers reported catches of O. beta in estuaries (Guanabara Bay, Sepetiba Bay, Santos Bay and Paranaguá Estuarine Complex). In addition, there were reports from other shallow areas outside adjacent estuaries (Bertioga and Peruíbe, in Sao Paulo State) and the first occurrence record for Laguna (Santa Catarina State), a southern estuarine zone (28° 29' 45″ S to 48° 45' 36″ W). In four estuaries along the Brazilian coast where O. beta was recorded, there are internal ports that trade with countries from the Gulf of Mexico and Caribbean Sea (species original range), indicating ballast water as a possible introduction route. In Laguna, the introduction may have occurred by maritime cabotage services. The reproductive capacity, the aquarists' interest, the absence of introduction policies aimed at this species and the cabotage fleet transportation may be factors that help further extend the dispersal of O. beta on the Brazilian coast.

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Artificial habitats, such as harbours and marinas, are entry doors for the introduction and dispersal of species. Surveys on fouling community in these habitats help to understand preventing environmental impacts and management of invasive species. Thus, a survey on fouling bryozoan fauna was carried out along 17 artificial habitats (eight harbours and nine marinas) from three coastal stretches in Southwestern Atlantic. A total of 55 species were identified, including 13 non-native, 33 cryptogenic and nine native taxa. Only five bryozoan species were found in more than 75% of sampled sites. Our analysis revealed that bryozoan fouling communities in artificial habitats do not vary significantly between commercial and recreational localities. However, we also found that faunal assemblages varied significantly along Brazilian coastal stretches that are distinguished by environmental conditions, such as salinity and temperature.

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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.

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Abstract The golden mussel is an aquatic invasive species that was introduced in South America in the '90s, including Brazil, and was firstly registered in 2001 in the Paraná state. This bivalve causes macrofouling issues because adhere in substrates and form dense aggregations, affecting especially hydroelectric power plants, and water treatment facilities, apart from the native biodiversity. The present research aimed to diagnose the distribution of Limnoperna fortunei in the Paraná state using environmental DNA (eDNA) from 174 sites from 12 basins, and scientific and technical previous records. L. fortunei eDNA was found in 90 sites from 11 hydrographic basins sampled. Most of the positive samples were detected in Iguaçu (42), Tibagi (15), and Ivaí (10) rivers basins. We also registered the first occurrence for five basins: Cinzas, Itararé, Ivaí, Pirapó e Ribeira rivers. Together, our and previous data recorded L. fortunei in 118 sites, between adult, larvae, and eDNA detection. Moreover, the results evidenced that eDNA is a low coast and reliable tool, and it may be very recommended for L. fortunei early detection and diagnosis. The present research was the greatest and most widespread survey for golden mussel prospection in a state in Brazil, supported a worrying scenario for Parana, with the urgent need for intense and continuous monitoring and prevention actions for controlling and mitigation of the L. fortunei impacts.

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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)

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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.

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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.

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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)

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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.

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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)

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Abstract 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. Finally, the tolerance of L. fortunei specimens to the stressor tested herein can help us understand the invasive capacity of this mussel during the establishment process.

Resumo 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. Finalmente, o conhecimento sobre a tolerância de L. fortunei ao estresse pode ajudar a entender a capacidade invasiva deste durante o processo de estabelecimento.

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