RESUMO

Dark Leathery Surface of Geoduck Clams (LSGC) is an alteration that affects the periostracum of the mantle and siphon of Panopea generosa from the northwest coast of Canada and Mexico. This alteration affects commercialization and possibly the survival of the clams. The cause of LSGC is unknown but has been correlated with presence of fungi and protozoans. We detected a similar alteration in Panopea globosa from Baja California, Mexico and the histophagous ciliate Uronema marinum was isolated from affected siphon tissue. U. marinum was identified by its morphology and by genetic analysis of the gene 18S rRNA. This is the first record of LSGC in P. globosa and the first identification of a histophagous protozoan associated with it.

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Massive occurrence of trichodinids is frequently accompanied by serious disease in fish farms. In this study, trichodinid species from the gills and skin of Nile tilapia (Oreochromis niloticus) farmed in the central-western region of Brazil (state of Goiás) were morphologically characterized. Dried slides were prepared from the parasites and were impregnated with silver nitrate (2%). Morphometric characteristics were determined and schematic drawings of the denticles were made using photomicrographs produced from the slides. Seven species of trichodinid ectoparasites (Protozoa: Ciliophora: Trichodinidae) were found parasitizing the gills: four of the genus Trichodina Ehrenberg, 1838; one of Tripartiella Lom, 1959; one of Paratrichodina Lom, 1963; and one of Trichodinella Srámek-Husek, 1953. On the body surface, three specimens of the genus Trichodina were identified. This study presents new geographical records of trichodinids in Brazil, thus confirming that Trichodina centrostrigeata, Trichodina compacta, Trichodina heterodentata, Paratrichodina africana and Tripartiella orthodens are widely distributed worldwide. Additionally, the first record of the genus Trichodinella in Brazil is presented.

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Abstract Massive occurrence of trichodinids is frequently accompanied by serious disease in fish farms. In this study, trichodinid species from the gills and skin of Nile tilapia (Oreochromis niloticus) farmed in the central-western region of Brazil (state of Goiás) were morphologically characterized. Dried slides were prepared from the parasites and were impregnated with silver nitrate (2%). Morphometric characteristics were determined and schematic drawings of the denticles were made using photomicrographs produced from the slides. Seven species of trichodinid ectoparasites (Protozoa: Ciliophora: Trichodinidae) were found parasitizing the gills: four of the genus Trichodina Ehrenberg, 1838; one of Tripartiella Lom, 1959; one of Paratrichodina Lom, 1963; and one of Trichodinella Ṧrámek-Huṧek, 1953. On the body surface, three specimens of the genus Trichodina were identified. This study presents new geographical records of trichodinids in Brazil, thus confirming that Trichodina centrostrigeata, Trichodina compacta, Trichodina heterodentata, Paratrichodina africana and Tripartiella orthodens are widely distributed worldwide. Additionally, the first record of the genus Trichodinella in Brazil is presented.

Resumo O parasitismo intenso por tricodinídeos está frequentemente relacionado à doença grave em fazendas de peixes. Neste estudo, espécies de tricodinídeos das brânquias e da pele de tilápias do Nilo (Oreochromis niloticus) cultivadas na região centro-oeste do Brasil (estado de Goiás) foram caracterizadas morfologicamente. As lâminas secas foram preparadas a partir dos parasitas e impregnadas com nitrato de prata (2%). As características morfométricas foram determinadas e desenhos esquemáticos dos dentículos foram confeccionados com fotomicrografias produzidas a partir das lâminas. Sete espécies de ectoparasitos tricodinídeos (Protozoa: Ciliophora: Trichodinidae) foram encontradas parasitando as brânquias: quatro do gênero Trichodina Ehrenberg, 1838; um de Tripartiella Lom, 1959; um de Paratrichodina Lom, 1963; e um de Trichodinella Ṧrámek-Huṧek, 1953. Na superfície do corpo, três espécimes do gênero Trichodina foram identificados. Este estudo apresenta novos registros geográficos de tricodinídeos no Brasil, confirmando que Trichodina centrostrigeata, Trichodina compacta, Trichodina heterodentata, Paratrichodina africana e Tripartiella orthodens estão amplamente distribuídas mundialmente. Adicionalmente, é apresentado o primeiro registro do gênero Trichodinella no Brasil.

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This paper characterizes the pattern of ectoparasite and endoparasite communities in an assemblage of 35 sympatric fish from different trophic levels in a tributary from the Amazon River system, northern Brazil. In detritivorous, carnivorous, omnivorous and piscivorous hosts, the species richness consisted of 82 ectoparasites and endoparasites, but protozoan ectoparasites such as Ichthyophthirius multifiliis, Piscinoodinium pillulare and Tripartiella sp. were dominant species predominated, such that they were present in 80% of the hosts. The taxon richness was in the following order: Monogenea > Nematoda > Digenea > Crustacea > Protozoa > Acanthocephala = Cestoda > Hirudinea. Among the hosts, the highest number of parasitic associations occurred in Satanoperca jurupari, Aequidens tetramerus, Hoplerythrinus unitaeniatus, Hoplosternum littorale, Cichlasoma amazonarum, Chaetobranchus flavescens, Squaliforma emarginata, Chaetobranchopsis orbicularis and Hoplias malabaricus. A weak positive correlation between ectoparasite abundance and length of the hosts was observed. Ectoparasite communities of detritivorous, carnivorous and omnivorous hosts were similar, but these differed from the communities of piscivorous hosts. Larval endoparasite species with low host specificity were the main determinants of the parasite infracommunity structure of the fish assemblage. Fish assemblage had few species of helminth that were specialist endoparasites, while many were parasites at the larval stage, infecting intermediate and paratenic hosts. Finally, carnivorous and omnivorous hosts harbored endoparasite communities that were more heterogeneous than those of detritivorous and piscivorous hosts. This result lends supports to the notion that the feeding habits of the host species are a significant factor in determining the endoparasites fauna.

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In the present paper, we described the first record of an epibiont protozoan Epistylis sp. Ehrenberg, 1830 (Ciliophora, Peritrichia) attached to Ergasilus chelangulatus Thatcher and Brasil-Sato, 2008, parasite of Pimelodus maculatus Lacépède, 1803 in Brazil, with electron microscope observations. Fish were collected in Veados River, state of São Paulo and the crustacean Ergasilus chelangulatus being registered for the first time in this river, expanding its geographical distribution in Brazil.

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RESUMO

In the present paper, we described the first record of an epibiont protozoan Epistylis sp. Ehrenberg, 1830 (Ciliophora, Peritrichia) attached to Ergasilus chelangulatus Thatcher and Brasil-Sato, 2008, parasite of Pimelodus maculatus Lacépède, 1803 in Brazil, with electron microscope observations. Fish were collected in Veados River, state of São Paulo and the crustacean Ergasilus chelangulatus being registered for the first time in this river, expanding its geographical distribution in Brazil.(AU)

No presente trabalho nós descrevemos o primeiro registro de um protozoário epibionte Epistylis sp. Ehrenberg, 1830 (Ciliophora, Peritrichia) aderido à Ergasilus chelangulatus Thatcher e Brasil-Sato, 2008, parasito de Pimelodus maculatus Lacépède, 1803 no Brasil, com observações de microscopia eletrônica. Os peixes foram coletados no Rio dos Veados, estado de São Paulo e o crustáceo Ergasilus chelangulatus está sendo registrado pela primeira vez neste rio, ampliando sua distribuição geográfica no Brasil.(AU)

Assuntos

RESUMO

In the present paper, we described the first record of an epibiont protozoan Epistylis sp. Ehrenberg, 1830 (Ciliophora, Peritrichia) attached to Ergasilus chelangulatus Thatcher and Brasil-Sato, 2008, parasite of Pimelodus maculatus Lacépède, 1803 in Brazil, with electron microscope observations. Fish were collected in Veados River, state of São Paulo and the crustacean Ergasilus chelangulatus being registered for the first time in this river, expanding its geographical distribution in Brazil.

No presente trabalho nós descrevemos o primeiro registro de um protozoário epibionte Epistylis sp. Ehrenberg, 1830 (Ciliophora, Peritrichia) aderido à Ergasilus chelangulatus Thatcher e Brasil-Sato, 2008, parasito de Pimelodus maculatus Lacépède, 1803 no Brasil, com observações de microscopia eletrônica. Os peixes foram coletados no Rio dos Veados, estado de São Paulo e o crustáceo Ergasilus chelangulatus está sendo registrado pela primeira vez neste rio, ampliando sua distribuição geográfica no Brasil.

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The determination of mean intensity of parasitism for colony-forming sessile protozoan such as Epistylis has been a great problem in parasitological studies. Some alternatives have been proposed by researchers for laboratory and field conditions. This study describes the criteria to establish the parasitic intensity score for epistylidid infestation in fish. Parasite distribution and the host-parasite relationship in four species of Brazilian cultured catfish and their hybrids are discussed. The highest prevalence rates were found in the hybrid jundiara, Leiarius marmoratus male × Pseudoplatystoma reticulatum female (96.4 %), followed by jurupoca, Hemisorubim platyrhynchos (60 %), and the hybrid surubim, Pseudoplatystoma corruscans male × P. reticulatum female (52.7 %). Positive correlation between parasitic intensity score and the fish size, weight, and relative condition factor were also observed. These findings indicate that Epistylis infestation in Brazilian catfish is an emerging disease in cultured fish.

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In the present work Trichodina reticulata and T. nobilis (Ciliophora: Trichodinidae) are morphologically characterised from ornamental freshwater fish culture in the State of Santa Catarina, Brazil. The prevalence of infection and a list of comparative measurements are discussed. We examined "southern platyfish" Xiphophorus maculatus (n = 35), "goldfish" Carassius auratus (n = 31), "guppy" Poecilia reticulata (n = 20), "sailfin molly" Poecilia latipinna (n = 6), "beta" Betta splendens (n = 2) and "spotted headstander" Chilodus punctatus (n = 1). After being anesthetised in a benzocaine solution, fishes were examined for parasitological evaluation. A total of 51.57% fishes were parasitised by Trichodina spp. Carassius auratus was the most parasitised species, followed by X. maculatus and P. reticulata. Beta splendens, C. punctatus and P. latipinna were not parasitised by any trichodinid species. Two species of Trichodina were collected from the skin of fish: T. nobilis was found in C. auratus, P. reticulata and X. maculatus and T. reticulata was only observed in C. auratus. The importance of adequate handling in ornamental fish culture are also discussed.

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RESUMO

In the present work Trichodina reticulata and T. nobilis (Ciliophora: Trichodinidae) are morphologically characterised from ornamental freshwater fish culture in the State of Santa Catarina, Brazil. The prevalence of infection and a list of comparative measurements are discussed. We examined "southern platyfish" Xiphophorus maculatus (n = 35), "goldfish" Carassius auratus (n = 31), "guppy" Poecilia reticulata (n = 20), "sailfin molly" Poecilia latipinna (n = 6), "beta" Betta splendens (n = 2) and "spotted headstander" Chilodus punctatus (n = 1). After being anesthetised in a benzocaine solution, fishes were examined for parasitological evaluation. A total of 51.57% fishes were parasitised by Trichodina spp. Carassius auratus was the most parasitised species, followed by X. maculatus and P. reticulata. Beta splendens, C. punctatus and P. latipinna were not parasitised by any trichodinid species. Two species of Trichodina were collected from the skin of fish: T. nobilis was found in C. auratus, P. reticulata and X. maculatus and T. reticulata was only observed in C. auratus. The importance of adequate handling in ornamental fish culture are also discussed.

No presente trabalho Trichodina reticulata e T. nobilis (Ciliophora: Trichodinidae) de peixes ornamentais de água doce cultivados no estado de Santa Catarina, Brasil são caracterizadas morfologicamente. A prevalência de infecção e uma lista comparative de medidas são discutidas. Foram examinados "platis" Xiphophorus maculatus (n = 35), "kinguios" Carassius auratus (n = 31), "guppys" Poecilia reticulata (n = 20), "molinésias" Poecilia latipinna (n = 6), "betas" Betta splendens (n = 2) e "espada" Chilodus punctatus (n = 1). Após a anestesia com solução de benzocaína, os peixes foram submetidos à avaliação parasitológca. Um total de 51,57% peixes estavam parasitados por Trichodina spp. Carassius auratus foi a espécie mais parasitada, seguida por X. maculatus e P. reticulata. Beta splendens, C. punctatus e P. latipinna não estavam parasitados por tricodinídeos. Duas species de Trichodina foram coletadas da superfície corporal dos peixes: T. nobilis foi encontrada em C. auratus, P. reticulata e X. maculatus e T. reticulata foi observada apenas em C. auratus. A importância do manejo adequado em cultivos de peixes ornamentais também foi discutida.

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We have generated 18S rRNA sequences for peritrichs collected in Brazil, including four Opercularia species, two different populations of Epistylis plicatilis (one epibiont and another free-living), and one additional Epistylis species. Our Opercularia species clustered with the previously available Opercularia microdiscum, corroborating the monophyly of this genus. The Epistylis sampled here clustered with previously sequenced species of this genus. The two populations of E. plicatilis collected in Brazil clustered closely together despite their different ecological contexts, whereas both were very divergent from the sample assigned to the same species previously sampled in China. If affirmed by additional morphological corroboration of species assignment, this observation would indicate that samples from different continents morphologically allocated in the same species may in fact belong to distant evolutionary lineages. More broadly, our results support the recognition of two major clades within Peritrichia. Given the robustness of their support, we suggest that these two clades should be formally recognized as orders, and propose the names Vorticellida and Operculariida to designate them. Furthermore, Epistylis species occurred in both orders, tending to occupy basal positions. This suggests that characters used to define this genus may be plesiomorphic for Peritrichia, so that Epistylis may in fact represent an assemblage of basal species retaining ancestral features.

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This study characterises morphologically Trichodina heterodentata Duncan, 1977 from channel catfish, Ictalurus punctatus (Rafinesque, 1818) in the State of Santa Catarina, Brazil. Body and gill smears were air-dried at room temperature, impregnated with silver nitrate and/or stained with Giemsa. Ten characteristics were selected to compare the present material with other morphological characterisations of T. heterodentata. Prevalence rate was 100%, mean intensity 89,333.70 (3,125 to 299,100 parasites per host). Trichodina heterodentata was considered medium-sized trichodinid with mean body diameter 59.4 +/- 8.5 microm, denticulate ring 38.5 +/- 4.5 microm, adhesive disc 60.2 +/- 6.7 microm diameter and 24.4 +/- 1.6 denticles. In relation to previous reports of T. heterodentata this material resembles in 90% of the analysed characters. This work confirms the biometrical variation that exists in the different populations of T. heterodentata. A list of hosts and comparative measurements of T. heterodentata are presented and the channel catfish is considered a new host.

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RESUMO

This study characterises morphologically Trichodina heterodentata Duncan, 1977 from channel catfish, Ictalurus punctatus (Rafinesque, 1818) in the State of Santa Catarina, Brazil. Body and gill smears were air-dried at room temperature, impregnated with silver nitrate and/or stained with Giemsa. Ten characteristics were selected to compare the present material with other morphological characterisations of T. heterodentata. Prevalence rate was 100 percent, mean intensity 89,333.70 (3,125 to 299,100 parasites per host). Trichodina heterodentata was considered medium-sized trichodinid with mean body diameter 59.4 ± 8.5 μm, denticulate ring 38.5 ± 4.5 μm, adhesive disc 60.2 ± 6.7 μm diameter and 24.4 ± 1.6 denticles. In relation to previous reports of T. heterodentata this material resembles in 90 percent of the analysed characters. This work confirms the biometrical variation that exists in the different populations of T. heterodentata. A list of hosts and comparative measurements of T. heterodentata are presented and the channel catfish is considered a new host.

Este estudo caracteriza morfologicamente Trichodina heterodentata Duncan, 1977 em bagre-do-canal, Ictalurus punctatus (Rafinesque, 1818) no Estado de Santa Catarina, Brasil. Esfregaços do corpo e brânquias foram secados à temperatura ambiente, impregnados com nitrato de Prata e/ou corados com Giemsa. Dez características foram selecionadas para comparar o presente material com as diferentes caracterizações morfológicas de T. heterodentata. A taxa de prevalência foi de 100 por cento, a intensidade média foi de 89.333.75 (3.125 a 299.100 parasitos por hospedeiro). Trichodina heterodentata foi considerado um tricodinídeo de tamanho médio com a média do diâmetro do corpo de 59,4 ± 8.5 μm, anel denticulado 38,5 ± 4,5 μm, disco adesivo 60,2 ± 6,7 μm de diâmetro e 24,4 ± 1,6 dentículos. Em relação a registros prévios de T. heterodentata, 90 por cento das características foram semelhantes. Este trabalho confirma a variação biométrica que existe em diferentes populações de T. heterodentata. Uma lista de hospedeiros e medidas comparativas de T. heterodentata são apresentadas e o bagre-do-canal considerado um novo hospedeiro.

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The ciliate Trichodina was recorded on the calanoid Notodiaptomus deitersi in a shallow, eutrophic reservoir, located in the centre-west of Brazil. The species was confirmed as Trichodina diaptomi, a species widely distributed in Europe, Africa, Asia and Australia. It was observed moving freely over the carapace of the copepod, and using its adhesive disc. This is the first record for the species in the Americas.

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Peritrich ciliates of the genus Trichodina are internal or external symbionts of invertebrate and vertebrate hosts. We describe here Trichodina ctenophorii n. sp., a symbiont of Mnemiopsis mccraydii and Beroë ovata (Phylum Ctenophora). The morphology of fixed and living specimens is revealed by silver impregnation, scanning electron microscopy, and differential interference microscopy. Distinguishing features of Trichodina ctenophorii include a denticular morphology composed of falcate, blunt-tipped blades, and long, straight thorns, with five pins per denticle. Trichodina ctenophorii is found only on the comb plates of these ctenophores. To the best of our knowledge, this is the first report of a trichodinid from the Gulf of Mexico and the first associated with ctenophores.

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