Dolops carvalhoi as a vector of Epistylis sp. between cultivated and wild specimens of Oreochromis niloticus in Brazil / Dolops carvalhoi como vetor de Epistylis sp. entre espécimes cultivados e silvestres de Oreochromis niloticus no Brasil

Epistyliasis has been characterized as an emergent disease which has a great impact on fish farms, especially on Oreochromis niloticus production systems. Although epidemiological important, information about the dispersion of these parasites and their mechanical vectors is scarce. The present study reported the cooccurrence of Epistylis sp. as an epibiont of Dolops carvalhoi, a parasitic crustacean of cultivated/wild specimens (from accidental release) of O. niloticus from a cage fish farm area in the Ilha Solteira Reservoir, Grande River, SP, Brazil. The co-occurrence of Epistylis sp. and D. carvalhoi, and their epibiont relationship registered in this study suppose that the Epistylis may use the crustaceans for dispersion and as mechanical vectors for the dissemination of diseases in wild and cultivated hosts. Moreover, exchange of parasites between wild and cultivated hosts is possible, considering both organisms (protozoan and argulid). Furthermore, the results of the present study demonstrate the need to monitor the areas adjacent to cage fish farms as a preventive measure for the dispersion of pathogens. This is the first report of epibiosis between Epistylis sp. and argulid parasites of cultivated and wild O. niloticus, contributing to knowledge about host-parasite specificity, geographical distribution, dispersion of etiological agents and epidemiology in aquaculture.(AU)

Epistilíase tem sido caracterizada como uma doença emergente de grande impacto nas pisciculturas, especialmente em sistemas de produção de Oreochromis niloticus. Embora seja importante epidemiologicamente, informações sobre a dispersão desses parasitas e seus vetores mecânicos são escassos. O presente estudo relata a coocorrência de Epistylis sp. como um epibionte de Dolops carvalhoi, um crustáceo parasita de espécimes cultivados e silvestres (de escapes acidentais) de O. niloticus em área de piscicultura de tanques-rede no reservatório de Ilha Solteira, Rio Grande, SP, Brasil. A coocorrência de Epistylis sp. e D. carvalhoi, e sua relação epibionte registrada neste estudo, supõem que Epistylis sp. possa utilizar os crustáceos para dispersão e como vetores mecânicos para a disseminação de doenças em hospedeiros silvestres e cultivados. Além disso, a troca de parasitas entre hospedeiros silvestres e cultivados é possível, considerando ambos os organismos (protozoários e argulídeos). Os resultados deste estudo, também demonstram a necessidade de monitorar as áreas adjacentes às pisciculturas como medida preventiva para a dispersão de patógenos. Este é o primeiro relato de epibiose entre Epistylis sp. e parasitas argulídeos de O. niloticus cultivados e silvestres, contribuindo para o conhecimento da especificidade parasitária do hospedeiro, distribuição geográfica, dispersão de agentes etiológicos e epidemiologia na aquicultura.(AU)

The first finding of Ostrea cf. puelchana (Bivalvia) living as epibiont on Callinectes exasperates (Decapoda) / Primeiro registro de Ostrea cf. puelchana (Bivalvia) vivendo como epibionte sobre Callinectes exasperates (Decapoda)

This paper describes the epibiosis of Ostrea cf. puelchana on Callinectes exasperatus (Gerstaecker, 1856), both collected from the estuary of the Paraíba River, in the state of Paraíba, northeastern Brazil. The basibiont crab was captured using a trap installed in mangrove area at a depth of about 2 meters. The oyster was closely attached to the left side of dorsal carapace covering most of the epibranchial, mesobranchial and metabranchial regions. Possible advantages and disadvantages for both the epibiont and the basibiont are discussed. We believe that young O. cf. puelchana may avoid a variety of potential predators due to the considerable movement capacity of C. exasperatus and may also serve as a small protective shield for the basibiont. However, the oyster, which is a bivalve with an epifaunal lifestyle, is likely to be negatively affected, mainly due to burrowing activity of the crab. This is the first record of epibiosis between bivalves of the genus Ostrea Linnaeus, 1758 and crabs of the genus Callinectes Stimpson, 1860.(AU)

O presente estudo descreve a epibiose de Ostrea cf. puelchana sobre Callinectes exasperatus(Gerstaecker, 1856), ambos coletados no estuário do Rio Paraíba, no estado da Paraíba, nordeste do Brasil.O caranguejo basibionte foi capturado usando uma armadilha instalada em área de mangue em cerca de 2metros de profundidade. A ostra estava fixada sobre o lado esquerdo da carapaça dorsal cobrindo grandeparte das regiões epibranquial, mesobranquial e metabranquial. Possíveis vantagens e desvantagens paraambos epibionte e basibionte são discutidas. O espécime jovem de O. cf. puelchana pode evitar umavariedade de predadores potenciais devido à considerável capacidade de deslocamento de C. exasperatus, aomesmo tempo, essa espécie pode atuar como um escudo protetor para o basibionte. Entretanto, o ostreídeopossui um estilo de vida epifaunal, podendo ser afetado de forma negativa, principalmente devido àatividade de escavação do caranguejo. Este é o primeiro registro de epibiose entre bivalves do gênero OstreaLinnaeus, 1758 e caranguejos do gênero Callinectes Stimpson, 1860.(AU)

First report of an epibiotic relationship between ciliates and planktonic copepods in a Brazilian floodplain

The peritrich ciliates are a widely distributed group of protozoa and include stalked and sedentary organisms, which may be solitary or colonial. These organisms are often observed as part of a relationship entitled epibiosis. This relationship is a facultative association between two organisms: the epibiont, which colonizes the surface of living substrates, and the basibiont, which hosts the epibionts. During a survey on the epibiotic relationship between ciliates e copepods in upper Paraná River floodplain-PR/MS Brazil, samples were taken in different types of environments (three rivers, three canals, 16 connected and 14 unconnected lakes), in a total of 36 sampling sites. Among these environments, 22 showed copepods infested by epibiont ciliates. The copepods Thermocyclops decipiens, Thermocyclops minutus and Notodiaptomus amazonicuswhere colonized by epibiont ciliates from the genus Epistylis.In this study, we reported for the first time, epibiosis in a Brazilian floodplain.(AU)

First report of an epibiotic relationship between ciliates and planktonic copepods in a Brazilian floodplain

The peritrich ciliates are a widely distributed group of protozoa and include stalked and sedentary organisms, which may be solitary or colonial. These organisms are often observed as part of a relationship entitled epibiosis. This relationship is a facultative association between two organisms: the epibiont, which colonizes the surface of living substrates, and the basibiont, which hosts the epibionts. During a survey on the epibiotic relationship between ciliates e copepods in upper Paraná River floodplain-PR/MS Brazil, samples were taken in different types of environments (three rivers, three canals, 16 connected and 14 unconnected lakes), in a total of 36 sampling sites. Among these environments, 22 showed copepods infested by epibiont ciliates. The copepods Thermocyclops decipiens, Thermocyclops minutus and Notodiaptomus amazonicuswhere colonized by epibiont ciliates from the genus Epistylis.In this study, we reported for the first time, epibiosis in a Brazilian floodplain.

Avaliação ectoparasitológica, hematológica e histopatológica de traíras Hoplias malabaricus Bloch, 1794 provenientes de açudes localizados no município de Sumé, estado da Paraíba / Ectoparasitologic, hematologic and histopathologic assessment of Hoplias malabaricus Bloch, 1794 from ponds located in Sumé municipality, state of Paraíba, Brazil

Hoplias malabaricus Bloch, 1794 é uma das espécies de peixes mais comumente encontrada nos açudes da Microrregião do Cariri Paraibano, todavia ainda não existem estudos na região sobre a sua fauna parasitária. Em virtude disso, o estudo objetivou caracterizar a fauna ectoparasitológica, o perfil hematológico e os achados histopatológicos das brânquias de H. malabaricus provenientes de quatro açudes localizados no município de Sumé/PB. Em cada açude foram capturados 10 exemplares e foi realizada a análise limnológica da água. Realizou-se a biometria dos exemplares e foram colhidas amostras sanguíneas por venopunção caudal. Os métodos de coleta de parasitos foram realizados segundo as recomendações da literatura. Além disso, foram coletadas amostras de brânquias para avaliação histopatológica. A comparação das médias foi feita pelo Teste Tukey a 5% de probabilidade. Os resultados mostram que a ectoparasitofauna de H. malabaricus provenientes de açudes localizados no município de Sumé/PB apresentou-se diversificada, sendo identificados vários táxons de ectoparasitos na superfície corporal e brânquias. A fauna parasitária promoveu alterações hematológicas e histopatológicas nas brânquias. Além disso, os resultados evidenciam uma relação de epibiose de Epistylis sp. com Lernaea cyprinacea e crustáceos branquiúros em H. malabaricus.(AU)

Hoplias malabaricus Bloch, 1794 is one of the fish species most commonly found in the micro-region ponds of Cariri in Paraíba; however there are no studies in the region on its parasitic fauna. Due to this, the study aimed to characterize the ectoparasitologic fauna, blood profile and histopathological findings of the gills of H. malabaricus from four ponds in Sumé/PB. At each pond 10 specimens were captured and limnological water analysis was performed as the biometrics of specimens and blood samples were collected by caudal venipuncture. Parasite collection methods were used according to literature recommendations. Also gill samples were collected for histopathological assessment. Comparison of the averages were made by Tukey test at a probability of 5%. The results show that H. malabaricus ectoparasite fauna from ponds located in Sumé/PB is diverse, once various ectoparasites taxons are identified on body surface and gills. The parasitic fauna promoted hematological and histopathological changes in the gills. The results show also an epibiosis relationship of Epistylis sp. with Lernaea cyprinacea and branchiurans crustaceans on H. malabaricus.(AU)

Avaliação ectoparasitológica, hematológica e histopatológica de traíras Hoplias malabaricus Bloch, 1794 provenientes de açudes localizados no município de Sumé, estado da Paraíba / Ectoparasitologic, hematologic and histopathologic assessment of Hoplias malabaricus Bloch, 1794 from ponds located in Sumé municipality, state of Paraíba, Brazil

Hoplias malabaricus Bloch, 1794 é uma das espécies de peixes mais comumente encontrada nos açudes da Microrregião do Cariri Paraibano, todavia ainda não existem estudos na região sobre a sua fauna parasitária. Em virtude disso, o estudo objetivou caracterizar a fauna ectoparasitológica, o perfil hematológico e os achados histopatológicos das brânquias de H. malabaricus provenientes de quatro açudes localizados no município de Sumé/PB. Em cada açude foram capturados 10 exemplares e foi realizada a análise limnológica da água. Realizou-se a biometria dos exemplares e foram colhidas amostras sanguíneas por venopunção caudal. Os métodos de coleta de parasitos foram realizados segundo as recomendações da literatura. Além disso, foram coletadas amostras de brânquias para avaliação histopatológica. A comparação das médias foi feita pelo Teste Tukey a 5% de probabilidade. Os resultados mostram que a ectoparasitofauna de H. malabaricus provenientes de açudes localizados no município de Sumé/PB apresentou-se diversificada, sendo identificados vários táxons de ectoparasitos na superfície corporal e brânquias. A fauna parasitária promoveu alterações hematológicas e histopatológicas nas brânquias. Além disso, os resultados evidenciam uma relação de epibiose de Epistylis sp. com Lernaea cyprinacea e crustáceos branquiúros em H. malabaricus.(AU)

Hoplias malabaricus Bloch, 1794 is one of the fish species most commonly found in the micro-region ponds of Cariri in Paraíba; however there are no studies in the region on its parasitic fauna. Due to this, the study aimed to characterize the ectoparasitologic fauna, blood profile and histopathological findings of the gills of H. malabaricus from four ponds in Sumé/PB. At each pond 10 specimens were captured and limnological water analysis was performed as the biometrics of specimens and blood samples were collected by caudal venipuncture. Parasite collection methods were used according to literature recommendations. Also gill samples were collected for histopathological assessment. Comparison of the averages were made by Tukey test at a probability of 5%. The results show that H. malabaricus ectoparasite fauna from ponds located in Sumé/PB is diverse, once various ectoparasites taxons are identified on body surface and gills. The parasitic fauna promoted hematological and histopathological changes in the gills. The results show also an epibiosis relationship of Epistylis sp. with Lernaea cyprinacea and branchiurans crustaceans on H. malabaricus.(AU)

Epibiosis in decapod crustaceans by stalked barnacle Octolasmis lowei (Cirripedia: Poecilasmatidae)

Stalked barnacles Octolasmis lowei Darwin, 1851 are frequently found attached to decapod crustaceans. Their epibiotic association depends on many factors, which are mainly related to characteristics of the host's biology. This study evaluated the infestation and distribution of stalked barnacles in the branchial chambers of crabs, and analyzed the data with respect to the host's sex, maturity stage, molt cycle and size. The crab species Arenaeus cribrarius Lamarck, 1818, Callinectes danae Smith, 1869, Callinectes ornatus Ordway, 1863, Hepatus pudibundus Herbst, 1785, Libinia ferreirae Brito Capello, 1871, and Persephona punctata Linnaeus, 1758 were sampled and found to be infested by O. lowei. No juvenile crabs were infested. The prevalence of infestation by O. lowei was significantly different among C. danae, C. ornatus, and H. pudibundus males and females. All infested hosts were in the intermolt period. The mean size of infested crabs was larger than that observed for non-infested individuals. Internally, stalked barnacles were concentrated on the central gills or walls and floor of branchial chambers, suggesting that these gills provide more favorable conditions for the settlement and development of these epibionts. These results highlight the relationship between epibiont infestation and host biology, as well as the role of decapod crustaceans as a suitable substrate for the development of stalked barnacle O. lowei.

Epibiosis in decapod crustaceans by stalked barnacle Octolasmis lowei (Cirripedia: Poecilasmatidae)

Stalked barnacles Octolasmis lowei Darwin, 1851 are frequently found attached to decapod crustaceans. Their epibiotic association depends on many factors, which are mainly related to characteristics of the host's biology. This study evaluated the infestation and distribution of stalked barnacles in the branchial chambers of crabs, and analyzed the data with respect to the host's sex, maturity stage, molt cycle and size. The crab species Arenaeus cribrarius Lamarck, 1818, Callinectes danae Smith, 1869, Callinectes ornatus Ordway, 1863, Hepatus pudibundus Herbst, 1785, Libinia ferreirae Brito Capello, 1871, and Persephona punctata Linnaeus, 1758 were sampled and found to be infested by O. lowei. No juvenile crabs were infested. The prevalence of infestation by O. lowei was significantly different among C. danae, C. ornatus, and H. pudibundus males and females. All infested hosts were in the intermolt period. The mean size of infested crabs was larger than that observed for non-infested individuals. Internally, stalked barnacles were concentrated on the central gills or walls and floor of branchial chambers, suggesting that these gills provide more favorable conditions for the settlement and development of these epibionts. These results highlight the relationship between epibiont infestation and host biology, as well as the role of decapod crustaceans as a suitable substrate for the development of stalked barnacle O. lowei.

Epibiosis in decapod crustaceans by stalked barnacle Octolasmis lowei (Cirripedia: Poecilasmatidae)

Stalked barnacles Octolasmis lowei Darwin, 1851 are frequently found attached to decapod crustaceans. Their epibiotic association depends on many factors, which are mainly related to characteristics of the host's biology. This study evaluated the infestation and distribution of stalked barnacles in the branchial chambers of crabs, and analyzed the data with respect to the host's sex, maturity stage, molt cycle and size. The crab species Arenaeus cribrarius Lamarck, 1818, Callinectes danae Smith, 1869, Callinectes ornatus Ordway, 1863, Hepatus pudibundus Herbst, 1785, Libinia ferreirae Brito Capello, 1871, and Persephona punctata Linnaeus, 1758 were sampled and found to be infested by O. lowei. No juvenile crabs were infested. The prevalence of infestation by O. lowei was significantly different among C. danae, C. ornatus, and H. pudibundus males and females. All infested hosts were in the intermolt period. The mean size of infested crabs was larger than that observed for non-infested individuals. Internally, stalked barnacles were concentrated on the central gills or walls and floor of branchial chambers, suggesting that these gills provide more favorable conditions for the settlement and development of these epibionts. These results highlight the relationship between epibiont infestation and host biology, as well as the role of decapod crustaceans as a suitable substrate for the development of stalked barnacle O. lowei.

Morphometric study of a Brazilian strain of Carchesium polypinum (Ciliophora: Peritrichia) attached to Pomacea figulina (Mollusca: Gastropoda), with notes on a high infestation

During an ecological study of the epibiotic relationship between ciliate protists and Pomacea figulina (Spix, 1827) (Gastropoda, Ampullariidae), originating from an urban stream in southeast Brazil, a high infestation by the peritrich ciliate Carchesium polypinum (Linnaeus, 1758) Ehrenberg, 1830 (Ciliophora, Peritrichia) associated to the shell of one mollusc among 23 was observed. We provided a morphological and morphometric study of C. polypinum using observations of specimens in vivo, after protargol staining, and examined using scanning electron microscopy. The Brazilian-population of C. polypinum is characterized by: size of zooid in vivo 89 µm x 57 µm on average; colony regularly dichotomously branched with usually up to 40 zooids; macronucleus usually J-shaped; single contractile vacuole located in the upper third of body; myoneme not continuous throughout the colony; stalks contract despite the discontinuity of their individual myonemes; polykinety comprises three peniculi, each consisting of three kineties. The high infestation showed here could be related to the preference for eutrophic environments showed by C. polypinum and suggested that ciliate epibionts may be ecologically important in aquatic habitats.

Epibionts on Arenaeus cribrarius (Brachyura: Portunidae) from Brazil

Mean prevalence and intensity of infestations by epibionts were evaluated in Arenaeus cribrarius (Lamarck, 1818), based on monthly samplings (May/1991 to April/1993), in Ubatuba, Brazil. Bryozoans were quantified in terms of colony numbers and barnacles by the number of specimens. Prevalence of infestation was determined in 1,914 individuals of A. cribrarius and assessed with respect to sex, maturity stage and season. No significant interaction was detected between epibionts and biological host factors. Males showed a higher infestation rate by Chelonibia patula (Ranzani, 1818) when compared to mature non-ovigerous females, yet Octolasmis lowei Darwin, 1851 infestation was associated to adult crabs. The ovigerous females of A. cribrarius showed a higher prevalence of infestation than males and non-ovigerous females, with lower infestations being recorded during winter. A synchrony between the life cycle of the epibionts and their hosts was evident and promotes the continuity of the former in the area.

Epibionts on Arenaeus cribrarius (Brachyura: Portunidae) from Brazil

Mean prevalence and intensity of infestations by epibionts were evaluated in Arenaeus cribrarius (Lamarck, 1818), based on monthly samplings (May/1991 to April/1993), in Ubatuba, Brazil. Bryozoans were quantified in terms of colony numbers and barnacles by the number of specimens. Prevalence of infestation was determined in 1,914 individuals of A. cribrarius and assessed with respect to sex, maturity stage and season. No significant interaction was detected between epibionts and biological host factors. Males showed a higher infestation rate by Chelonibia patula (Ranzani, 1818) when compared to mature non-ovigerous females, yet Octolasmis lowei Darwin, 1851 infestation was associated to adult crabs. The ovigerous females of A. cribrarius showed a higher prevalence of infestation than males and non-ovigerous females, with lower infestations being recorded during winter. A synchrony between the life cycle of the epibionts and their hosts was evident and promotes the continuity of the former in the area.

Morphometric study of a Brazilian strain of Carchesium polypinum (Ciliophora: Peritrichia) attached to Pomacea figulina (Mollusca: Gastropoda), with notes on a high infestation

During an ecological study of the epibiotic relationship between ciliate protists and Pomacea figulina (Spix, 1827) (Gastropoda, Ampullariidae), originating from an urban stream in southeast Brazil, a high infestation by the peritrich ciliate Carchesium polypinum (Linnaeus, 1758) Ehrenberg, 1830 (Ciliophora, Peritrichia) associated to the shell of one mollusc among 23 was observed. We provided a morphological and morphometric study of C. polypinum using observations of specimens in vivo, after protargol staining, and examined using scanning electron microscopy. The Brazilian-population of C. polypinum is characterized by: size of zooid in vivo 89 µm x 57 µm on average; colony regularly dichotomously branched with usually up to 40 zooids; macronucleus usually J-shaped; single contractile vacuole located in the upper third of body; myoneme not continuous throughout the colony; stalks contract despite the discontinuity of their individual myonemes; polykinety comprises three peniculi, each consisting of three kineties. The high infestation showed here could be related to the preference for eutrophic environments showed by C. polypinum and suggested that ciliate epibionts may be ecologically important in aquatic habitats.

Morphometric study of a Brazilian strain of Carchesium polypinum (Ciliophora: Peritrichia) attached to Pomacea figulina (Mollusca: Gastropoda), with notes on a high infestation

During an ecological study of the epibiotic relationship between ciliate protists and Pomacea figulina (Spix, 1827) (Gastropoda, Ampullariidae), originating from an urban stream in southeast Brazil, a high infestation by the peritrich ciliate Carchesium polypinum (Linnaeus, 1758) Ehrenberg, 1830 (Ciliophora, Peritrichia) associated to the shell of one mollusc among 23 was observed. We provided a morphological and morphometric study of C. polypinum using observations of specimens in vivo, after protargol staining, and examined using scanning electron microscopy. The Brazilian-population of C. polypinum is characterized by: size of zooid in vivo 89 µm x 57 µm on average; colony regularly dichotomously branched with usually up to 40 zooids; macronucleus usually J-shaped; single contractile vacuole located in the upper third of body; myoneme not continuous throughout the colony; stalks contract despite the discontinuity of their individual myonemes; polykinety comprises three peniculi, each consisting of three kineties. The high infestation showed here could be related to the preference for eutrophic environments showed by C. polypinum and suggested that ciliate epibionts may be ecologically important in aquatic habitats.

Epibionts on Arenaeus cribrarius (Brachyura: Portunidae) from Brazil

Mean prevalence and intensity of infestations by epibionts were evaluated in Arenaeus cribrarius (Lamarck, 1818), based on monthly samplings (May/1991 to April/1993), in Ubatuba, Brazil. Bryozoans were quantified in terms of colony numbers and barnacles by the number of specimens. Prevalence of infestation was determined in 1,914 individuals of A. cribrarius and assessed with respect to sex, maturity stage and season. No significant interaction was detected between epibionts and biological host factors. Males showed a higher infestation rate by Chelonibia patula (Ranzani, 1818) when compared to mature non-ovigerous females, yet Octolasmis lowei Darwin, 1851 infestation was associated to adult crabs. The ovigerous females of A. cribrarius showed a higher prevalence of infestation than males and non-ovigerous females, with lower infestations being recorded during winter. A synchrony between the life cycle of the epibionts and their hosts was evident and promotes the continuity of the former in the area.

Is the occurrence of caprellid amphipods associated with Sargassum (Phaeophyta) influenced by algal and hydrozoan epibiosis?

The presence of epiphytic organisms can influence the distribution of macroinvertebrates associated with algae. This study evaluated the influence of Sargassum epibiosis by epiphytic algae and hydroids on the occurrence of caprellid amphipods. The sampling was carried out on Sargassum beds of Ubatuba beaches, northern coast of São Paulo state, in October 2006. The presence of epiphytic algae and hydroids on Sargassum fronds was evaluated using five cover categories. Epiphytic algae showed significant cover differences among beaches, while hydroids occurrence was more uniform, without significant differences on the levels of epibiosis. None of the caprellid species identified showed differences in its density among beaches. Despite the epibiosis variation, it was not a determinant factor in the distribution of caprellid species.

Is the occurrence of caprellid amphipods associated with Sargassum (Phaeophyta) influenced by algal and hydrozoan epibiosis?

The presence of epiphytic organisms can influence the distribution of macroinvertebrates associated with algae. This study evaluated the influence of Sargassum epibiosis by epiphytic algae and hydroids on the occurrence of caprellid amphipods. The sampling was carried out on Sargassum beds of Ubatuba beaches, northern coast of São Paulo state, in October 2006. The presence of epiphytic algae and hydroids on Sargassum fronds was evaluated using five cover categories. Epiphytic algae showed significant cover differences among beaches, while hydroids occurrence was more uniform, without significant differences on the levels of epibiosis. None of the caprellid species identified showed differences in its density among beaches. Despite the epibiosis variation, it was not a determinant factor in the distribution of caprellid species.

Attachment of the peritrich epibiont Zoothamnium intermedium Precht, 1935 (Ciliophora, Peritrichia) to artificial substrates in a natural environment

Peritrich ciliates are commonly found as epibionts, colonizing living organisms, or attached to non-living substrates in freshwater, estuarine and marine environments. Several species of peritrich epibionts are obligate, which means that they are able to only colonize other organisms, while others are facultative attaching to living or non-living substrates. The peritrich Zoothamnium intermedium is commonly found as epibiont on the copepod species Acartia tonsa and Eurytemora affinis in Chesapeake Bay, USA. Previous studies demonstrated that Z. intermedium is not able to attach to non-living substrates in the laboratory; with free-swimming stages (telotrochs) dying when living substrates are not available for colonization. The present study investigated the ability of Z. intermdium to colonize artificial substrates in the field. Observations were carried out while the peritrich ciliate was colonizing copepods in Rhode River, a tributary of Chesapeake Bay. Results demonstrated that four species of Zoothamnium were recovered from artificial substrates, but none of them was Z. intermedium. At the same time, Z. intermedium was colonizing adults and copepodites of E. affinis and A. tonsa during the whole study period. These results, in addition to laboratory observations, suggest that Z. intermedium is an obligate epibiont.

Ciliados peritríquios são normalmente encontrados como epibiontes, colonizando substratos vivos, ou em substratos inanimados em ambientes de água doce, estuarinos e marinhos. Muitas espécies de peritríquios epibiontes podem ser consideradas obrigatórias quando estão aptas a colonizar apenas substratos vivos, ou facultativos quando conseguem colonizar substratos vivos ou inanimados. A espécie de ciliado peritríquio Zoothamnium intermedium é encontrada colonizando os copépodos Acartia tonsa e Eurytemora affinis na Chesapeake Bay, EUA. Estudos preliminares demonstraram que Z. intermedium não consegue colonizar substratos inanimados em laboratório e que os estágios livre-natantes (telotróquios) morrem quando não estão expostos a algum substrato vivo. No presente estudo, foi investigada a habilidade de Z. intermedium colonizar substratos artificiais no campo. As observações foram realizadas no Rhode River, um afluente da Chesapeake Bay, enquanto Z. intermedium era encontrado colonizando copépodos. Os resultados demonstraram que quatro espécies de Zoothamnium colonizaram os substratos artificiais, mas nenhuma delas era Z. intermedium. No mesmo período, Z. intermedium foi encontrado colonizando copepoditos e adultos de A. tonsa e E. affinis. Estes resultados, juntamente com as observações de laboratório, sugerem que Z. intermedium é um epibionte obrigatório.

Attachment of the peritrich epibiont Zoothamnium intermedium Precht, 1935 (Ciliophora, Peritrichia) to artificial substrates in a natural environment

Peritrich ciliates are commonly found as epibionts, colonizing living organisms, or attached to non-living substrates in freshwater, estuarine and marine environments. Several species of peritrich epibionts are obligate, which means that they are able to only colonize other organisms, while others are facultative attaching to living or non-living substrates. The peritrich Zoothamnium intermedium is commonly found as epibiont on the copepod species Acartia tonsa and Eurytemora affinis in Chesapeake Bay, USA. Previous studies demonstrated that Z. intermedium is not able to attach to non-living substrates in the laboratory; with free-swimming stages (telotrochs) dying when living substrates are not available for colonization. The present study investigated the ability of Z. intermdium to colonize artificial substrates in the field. Observations were carried out while the peritrich ciliate was colonizing copepods in Rhode River, a tributary of Chesapeake Bay. Results demonstrated that four species of Zoothamnium were recovered from artificial substrates, but none of them was Z. intermedium. At the same time, Z. intermedium was colonizing adults and copepodites of E. affinis and A. tonsa during the whole study period. These results, in addition to laboratory observations, suggest that Z. intermedium is an obligate epibiont.

Ciliados peritríquios são normalmente encontrados como epibiontes, colonizando substratos vivos, ou em substratos inanimados em ambientes de água doce, estuarinos e marinhos. Muitas espécies de peritríquios epibiontes podem ser consideradas obrigatórias quando estão aptas a colonizar apenas substratos vivos, ou facultativos quando conseguem colonizar substratos vivos ou inanimados. A espécie de ciliado peritríquio Zoothamnium intermedium é encontrada colonizando os copépodos Acartia tonsa e Eurytemora affinis na Chesapeake Bay, EUA. Estudos preliminares demonstraram que Z. intermedium não consegue colonizar substratos inanimados em laboratório e que os estágios livre-natantes (telotróquios) morrem quando não estão expostos a algum substrato vivo. No presente estudo, foi investigada a habilidade de Z. intermedium colonizar substratos artificiais no campo. As observações foram realizadas no Rhode River, um afluente da Chesapeake Bay, enquanto Z. intermedium era encontrado colonizando copépodos. Os resultados demonstraram que quatro espécies de Zoothamnium colonizaram os substratos artificiais, mas nenhuma delas era Z. intermedium. No mesmo período, Z. intermedium foi encontrado colonizando copepoditos e adultos de A. tonsa e E. affinis. Estes resultados, juntamente com as observações de laboratório, sugerem que Z. intermedium é um epibionte obrigatório.

Fouling resistance investigations of seaweed products / Investigações de resistência à incrustação de produtos de algas marinhas

Any solid, unprotected, and undefended surface in the aquatic environment will be fouled. Fouling, on the other hand, can affect a wide range of species that can tolerate some epibiosis. Several others, on the other hand, aggressively keep the epibionts off their body surface (antifouling). Antifouling defenses are built into marine plants like seaweed and seagrass. They do have a distinctive surface structure with tightly packed needle-like peaks and antifouling coverings, which may hinder settling bacteria's ability to cling. Chemical antifouling resistance is most probably a biological reaction to epibiosis' ecological drawbacks, especially for organisms capable of performing photosynthesis. The goal of this study was to see how effective natural compounds derived from littoral seaweeds were in preventing fouling. The brown mussel, an important fouling organism, was evaluated in laboratory bioassays against fifty-one populations' crude organic extracts including fort-two macroalgae species. Antifouling activity, exhibited a distinct phylogenetic pattern, with red macroalgae having the largest share of active species, subsequently brown macroalgae. Antifouling action in green seaweeds has never been significant. Seven species showed some level of induced antifouling defense. Our findings appear to back up previous findings about secondary metabolite synthesis in seaweeds, indicating that in the hunt for novel antifoulants, researchers should concentrate their efforts on tropical red macroalgae.

Resumo contaminada. A incrustação, por outro lado, pode afetar uma ampla gama de espécies que podem tolerar alguma epibiose. Vários outros, por outro lado, mantêm agressivamente os epibiontes fora de sua superfície corporal (anti-incrustante). As defesas anti-incrustantes são construídas em plantas marinhas como algas marinhas e ervas marinhas. Elas têm uma estrutura de superfície distinta com picos semelhantes a agulhas bem compactadas e coberturas anti-incrustantes, o que pode dificultar a capacidade de fixação das bactérias. A resistência química anti-incrustante é provavelmente uma reação biológica às desvantagens ecológicas da epibiose, especialmente para organismos capazes de realizar fotossíntese. O objetivo deste estudo foi verificar a eficácia dos compostos naturais derivados de algas marinhas do litoral na prevenção da incrustação. O mexilhão-marrom, importante organismo incrustante, foi avaliado em bioensaios de laboratório contra extratos orgânicos brutos de 51 populações, incluindo duas espécies de macroalgas. A atividade anti-incrustante exibiu um padrão filogenético distinto, com macroalgas vermelhas tendo a maior participação de espécies ativas, posteriormente macroalgas marrons. A ação anti-incrustante em algas verdes nunca foi significativa. Sete espécies apresentaram algum nível de defesa anti-incrustante induzida. Nossas descobertas parecem corroborar descobertas anteriores sobre a síntese de metabólitos secundários em algas marinhas, indicando que, na busca por novos anti-incrustantes, os pesquisadores devem concentrar seus esforços em macroalgas vermelhas tropicais.