Community ecology of the metazoan parasites of the Atlantic thread herring, Opisthonema oglinum (Lesueur, 1818) (Actinopterygii: Clupeidae) from the Sepetiba Bay, Rio de Janeiro, Brazil / Ecologia da comunidade dos metazoários parasitos da sardinha bandeira Opisthonema oglinum (Lesueur, 1818) (Actinopterygii: Clupeidae) da Baía de Sepetiba, Rio de Janeiro, Brasil

This study aimed to evaluate the parasitic fauna of Opisthonema oglinum (Lesueur, 1818) from Southeastern Brazil. Between September 2017 and March 2018, a total of 100 specimens of O. oglinum from the Sepetiba Bay, Rio de Janeiro, Brazil (22°54'S, 43°34'W) were examined. Ninety one specimens of O. oglinum were parasitized by at least one species of metazoan with a mean of 5.84 ± 7.98 parasites/fish. Seven species were collected: 2 digeneans, 2 monogeneans, 2 copepods and 1 nematode. The digenean Parahemiurus merus (Linton) was the most abundant and dominant species, representing 43% of metazoan parasites collected. The parasite species richness was positively correlated with the total length of the hosts. Only Neobomolochus elongatus Cressey showed a positive correlation between host's total length and parasite prevalence. The mean parasite species diversity was not correlated with host's total length, but significant differences among the mean parasite diversity between males and females was observed. Opisthonema oglinum represents a new host record for Caligus mutabilis Wilson, Hysterothylacium sp. and Cribomazocraes travassosi Santos and Kohn. The copepod N. elongatus is recorded for the first time on the Brazilian coast.

Este estudo teve como objetivo avaliar a fauna parasitária de Opisthonema oglinum (Lesueur, 1818) do Sudeste do Brasil. No período entre setembro de 2017 e março de 2018, um total de 100 espécimes de O. oglinum provenientes da Baía de Sepetiba, Rio de Janeiro, Brasil (22°54'S; 43°34'O), foram examinados. Noventa espécimes de O. oglinum estavam parasitados por pelo menos uma espécie de metazoário com média de 5,84 ± 7,98 parasitos/peixe. Sete espécies foram coletadas: 2 digenéticos, 2 monogenéticos, 2 copépodes e 1 nematoide. O digenético Parahemiurus merus (Linton) foi à espécie mais abundante e dominante, representando 43% dos metazoários parasitos coletados. A riqueza parasitária foi correlacionada com o comprimento total do hospedeiro. Apenas Neobomolochus elongatus Cressey apresentou correlação positiva entre o comprimento total do hospedeiro e a prevalência parasitária. A diversidade média de espécies de parasitos não apresentou correlação com o comprimento total do hospedeiro, mas foram observadas diferenças significativas entre a diversidade média de parasitos entre machos e fêmeas. Opisthonema oglinum representa um novo registro de hospedeiro para Caligus mutabilis Wilson, Hysterothylacium sp. e Cribomazocraes travassosi Santos and Kohn. O copépode N. elongatus é registrado pela primeira vez na costa Brasileira.

A new species of Tereancistrum (Monogenea: Dactylogyridae), parasite of Prochilodus lineatus (Characiformes: Prochilodontidae) from southeast Brazil / Uma nova espécie de Tereancistrum (Monogenea: Dactylogyridae), parasito de Prochilodus lineatus (Characiformes: Prochilodontidae) do sudeste do Brasil

Abstract A new species of Tereancistrum Kritsky, Thatcher & Kayton, 1980 collected of Prochilodus lineatus gills from the Batalha River, Tietê-Batalha basin, São Paulo State, Brazil is described. The new species can be distinguished from its congeners mainly by the configuration of the ventral bar, which has an anvil-shaped characteristic with corrugated anterior projection. Tereancistrum takemotoi n. sp. is morphologically similar to T. toksonum Lizama, Takemoto & Pavanelli, 2004 in terms of their dorsal bars (Y-shaped), their dorsal anchors with divergent roots (superficial and deep) wherein their deep root rather elongated, and by the fact that they both have the male copulatory organ counterclockwise. However, only T. takemotoi n. sp. presents the male copulatory organ with 2» rings and shows undulations in the anterior margin of the dorsal bar. These undulations are absent in T. toksonum (which only has 1» rings). This is the fourth Tereancistrum species described for P. lineatus and the first described for the region from the Tietê-Batalha basin.

Resumo É descrita uma nova espécie de Tereancistrum Kritsky, Thatcher & Kayton, 1980, coletada das brânquias de Prochilodus lineatus do rio Batalha, bacia do Tietê-Batalha, estado de São Paulo, Brasil. A nova espécie pode ser diferenciada de seus congêneres, principalmente pela configuração da barra ventral, que tem o formato de bigorna e apresenta uma projeção anterior com ondulações. Tereancistrum takemotoi n. sp. é morfologicamente semelhante a T. toksonum Lizama, Takemoto & Pavanelli, 2004, em termos de suas barras dorsais (em forma de Y), suas âncoras dorsais com raízes divergentes (superficiais e profundas) sendo que a raiz profunda é bastante alongada, e pelo fato de ambos terem o órgão copulatório masculino no sentido anti-horário. No entanto, apenas T. takemotoi n. sp. apresenta o órgão copulatório masculino com 2» anéis e também exibe ondulações na margem anterior da barra dorsal, diferentemente do T. toksonum (que possui apenas 1» anel em seu órgão copulatório masculino). Essa é a quarta espécie de Tereancistrum descrita para P. lineatus e a primeira descrita para a região da bacia do Tietê-Batalha.

Diversity of monogenean parasites on gills of fishes from the Matapi River, in the Brazilian Amazon / Diversidade de parasitos monogeneas nas brânquias de peixes do Rio Matapi, na Amazônia brasileira

Abstract This study investigated the fauna of monogeneans on gills of 13 fish species from the Matapi River, Brazilian Amazon. A total 548 fish belonging to 13 species (1 Anostomidae, 3 Characidae, 1 Curimatidae, 1 Hemiodontidae, 2 Serrasalmidae, 3 Scianidae, 1 Ageneiosidae and 1 Tetradontidae) were examined. From these fish, 6 species were infected and with a total prevalence of 22.4%. Monogeneans collected are represented by the following taxa: Anacanthorus gravihamulatus, Notozothecium minor, Notozothecium penetrarum, Diplectanum piscinarius, Aetheolabes goeldiensis, Euryhaliotrema succedanus, Anacanthorus jegui, Urocleidoides astyanacis, Urocleidoides strombicirrus, Euryhaliotrema sp. and Urocleidoides spp. There was a variation in the prevalence, mean intensity and mean abundance of monogeneans among the host populations examined. Monogeneans of Metynnis lippincottianus, Plagioscion squamosissimus, Astyanax bimaculatus and Curimata incompta presented a highly aggregated dispersion pattern. Body weight of M. lippincottianus and C. incompta presented a weak positive correlation with abundance of parasites. Lastly, this is first study for 12 fish species from the Matapi River and the first report of E. succedanus for Plagioscion surinamensis and N. penetrarum for Serrasalmus rhombeus.

Resumo Este estudo investigou a fauna de monogeneas das brânquias de 13 espécies de peixes do Rio Matapi, na Amazônia brasileira. Foram examinados um total de 548 peixes pertencentes a 13 espécies (1 Anostomidae, 3 Characidae, 1 Curimatidae, 1 Hemiodontidae, 2 Serrasalmidae, 3 Scianidae, 1 Ageneiosidae e 1 Tetradontidae). Entre esses peixes, 6 espécies estavam infectadas e houve uma prevalência total de 22,4%. As espécies de monogeneas coletadas foram distribuídas nos seguintes táxons: Anacanthorus gravihamulatus, Notozothecium minor, Notozothecium penetrarum Diplectanum piscinarius, Euryhaliotrema sp., Aetheolabes goeldiensis, Euryhaliotrema succedanus, Anacanthorus jegui, Urocleidoides astyanacis, Urocleidoides strombicirrus Urocleidoides spp. Houve variação na prevalência, intensidade média e abundância média de monogeneas entre as populações hospedeiras. Monogeneas em Metynnis lippincottianus, Plagioscion squamosissimus, Astyanax bimaculatus e Curimata incompta apresentaram um padrão de dispersão altamente agregado. O peso corporal de M. lippincottianus do Rio Matapi mostrou uma correlação positiva fraca com a abundância de A. jegui. O comprimento de C. incompta também mostrou uma correlação positiva fraca com abundância de Urocleidoides spp. Por fim, este é primeiro estudo para 12 espécies de peixes da bacia do Rio Matapi e registra pela primeira vez E. succedanus para Plagioscion surinamensis e N. penetrarum para Serrasalmus rhombeus.

Species of Anisakidae nematodes and Clinostomum spp. infecting lisa Mugil curema (Mugilidae) intended for human consumption in Mexico / Espécies de nematoides Anisakidae e Clinostomum spp. infectando tainhas Mugil curema (Mugilidae) destinadas ao consumo humano no México

Abstract Anisakisspp. nematodes are potentially zoonotic parasites; that infects a wide variety of aquatic species worldwide, with marine fish being the paratenic hosts. The aim of study was identify the presence of Anisakidae nematodes, and other parasites in Mugil curema . A total of 96 M . curema obtained from local markets in Tulancingo, Hidalgo, Mexico, were analyzed by necropsy. Only five M . curema present nematode collection in epaxial muscle. The tissues with the highest prevalence of parasites were identified, and samples of epaxial muscle with larval migration analyzed by histopathology. Visible parasites in necropsy tissues were classified according to their morphology. Nematode found in the liver were Contracaecum spp. (41.17%) and Pseudoterranova spp. third stage (7.36%); in the caudal part of the kidney were Anisakis spp. (13.23%), Pseudoterranova spp. third stage (11.77%) and Contracaecum spp. (5.88%); and in epaxial muscle were Anisakis spp. Larva I (5.88%) and Pseudoterranova spp (4.42%). In one fish, Clinostomum spp. was detected in epaxial caudal muscle. The present work reports for the first time the presence of nematodes of the family Anisakidae and Clinostonum spp. metacercariae, with zoonotic potential, in M . curema intended for human consumption in Tulancingo, Hidalgo, Mexico.

Resumo Anisakisspp. são parasitas potencialmente zoonóticos que infectam uma grande variedade de espécies aquáticas em todo o mundo, sendo os peixes marinhos hospedeiros paratênicos. O objetivo deste estudo foi identificar a presença de nematóides da família Anisakidae e de outros parasitas em peixes Mugil curema . Um total de 96 M . curema , obtidos em mercados locais em Tulancingo, Hidalgo, México, foram submetidos a necropsia. Apenas cinco M. curema apresentaram coleção de nematóides no músculo epaxial. Os tecidos com maior prevalência de parasitas foram identificados e amostras do músculo epaxial com migração larval foram analisadas por histopatologia. Os nematóides encontrados no fígado foram Contracaecum spp. (41,17%) e Pseudoterranova spp. terceira etapa (7,36%); na parte caudal do rim Anisakis spp. (13,23%), Pseudoterranova spp. terceira etapa (11,77%) e Contracaecum spp. (5,88%); e no músculo epaxial Anisakis spp. larva I (5,88%) e Pseudoterranova spp. (4,42%). Em um peixe, Clinostomum spp. foi detectado no músculo caudal epaxial. O presente trabalho relata pela primeira vez a presença de nematóides da família Anisakidae e Clinostonum spp. metacercárias, com potencial zoonótico, em M. curema destinado ao consumo humano em Tulancingo, Hidalgo, México.

Phyllodistomum vaili(Plagiorchiida: Gorgoderidae) infecting Parupeneus rubescens (Perciformes: Mullidae): morphology and phylogeny / Phyllodistomum vaili (Plagiorchiida: Gorgoderidae) infectando Parupeneus rubescens (Perciformes: Mullidae): morfologia e filogenia

Abstract Knowledge of the Arabian Gulf fish's parasite fauna is very poor. Until recently, only scattered reports from different locations are known for ecto- and endoparasites. Therefore, the present study aimed to investigate the digenean species that infects one of the most economically fish species in the Arabian Gulf, the rosy goatfish Parupeneus rubescens . One plagiorchiid species has been described, belonging to the Gorgoderidae family, and has been named as Phyllodistomum vaili Ho, Bray, Cutmore, Ward & Cribb, 2014 based on its morphological and morphometric characteristics. In order to accurately classify and characterize this plagiorchiid species, molecular analysis was carried out using both nuclear 18S and 28S rRNA gene regions and revealed that the present plagiorchiid species was associated with other species belonging to the Gorgoderidae family and deeply embedded in the Phyllodistomum genus, closely related to the previously described P. vaili (gb- KF013187.1, KF013173.1). The present study therefore revealed that the species Phyllodistomum is the first account as endoparasites from the rosy goatfish inhabiting the Arabian Gulf.

Resumo O conhecimento da fauna de parasitas dos peixes do Golfo Árabe é escasso. Atualmente, apenas relatórios dispersos de diferentes locais são conhecidos para ecto e endoparasitas. Portanto, o presente estudo teve como objetivo investigar as especies digenéticas que infectam uma das espécies economicamente mais importantes do Golfo Arábico, o peixe-cabra rosado Parupeneus rubescens . Uma espécie de plagiorquídeo foi descrita, pertencente à família Gorgoderidae e foi denominada Phyllodistomum vaili Ho, Bray, Cutmore, Ward & Cribb, 2014, com base em suas propriedades morfológicas e morfométricas. A fim de classificar e caracterizar com precisão essa espécie de plagiorquídeo, a análise molecular foi realizada usando as regiões nucleares do gene 18S e 28S rRNA, revelando que a atual espécie de plagiorchídeo estava associada a outras espécies pertencentes à família Gorgoderidae e, profundamente incorporada ao gênero Phyllodistomum , intimamente relacionado ao P. vaili descrito anteriormente (gb - KF013187.1, KF013173.1). O presente estudo revelou, portanto, que a espécie Phyllodistomum vailli é o primeiro relato como endoparasita do peixe-cabra rosado que habita o Golfo Arábico.

Infection by Platynosomum illiciens (= P. fastosum) in domestic cats of Araguaína, Tocantins, northern Brazil / Infecção por Platynosomum illiciens (= P. fastosum) em gatos domésticos de Araguaína, Tocantins, Norte do Brasil

Abstract Platynosomiasis is a hepatopathy caused by Platynosomum illiciens(= P. fastosum) (Trematoda: Dicrocoelidae), which occurs mainly in domestic and wild cats in tropical and subtropical areas. The objective of this study was to verify the occurrence of P. illiciens infection in domestic cats in the city of Araguaína, Tocantins, Brazil, using necropsy and coproparasitological tests. Additionally, we aimed to evaluate the use of two different techniques to diagnose P. illiciens infection in domestic cats and verify whether this parasitism was associated with individual feline characteristics. For this, 54 cats of different ages were analyzed. The percentage of infection was 33.3% (CI = 21.1-47.5%), parasite load was 9-509, mean intensity was 151.7, and mean abundance was 50.5 trematodes per animal. The risk of infection was higher for females than for males (OR = 5.00; P = 0.017). The spontaneous sedimentation coproparasitological test demonstrated the greatest sensitivity and specificity in diagnosing P. illiciens. This study is the first to report the occurrence of P. illiciens in cats in the state of Tocantins, northern Brazil.

Resumo A platinosomose é uma hepatopatia causada por Platynosomum illiciens(= P. fastosum) (Trematoda: Dicrocoelidae), que ocorre principalmente em felinos domésticos e selvagens de áreas tropicais e subtropicais. O objetivo deste trabalho foi verificar a ocorrência de P. illiciens em gatos domésticos do município de Araguaína, Tocantins, Brasil, por meio de necrópsia e exames coproparasitológicos, bem como avaliar o uso de diferentes técnicas no diagnóstico de P. illiciens em gatos domésticos e verificar a associação da parasitose com características individuais dos felinos. O estudo foi realizado em 54 gatos com diferentes idades, machos e fêmeas. O percentual de infecção foi de 33,3% (IC= 21,1% - 47,5%), a carga parasitária observada foi de 09-509, a intensidade média de 151,7 e a abundância média de 50,5 trematódeos por animal. As fêmeas apresentaram maior chance de infecção do que os machos (OR=5,00; P=0,017). O teste coproparasitológico que demonstrou maior sensibilidade e especificidade foi o de sedimentação espontânea. O presente estudo faz o primeiro relato da ocorrência de P. illiciens em gatos no estado do Tocantins, região Norte do Brasil.

First report of Diplostomidae metacercariae (Trematoda: Digenea) in African catfish Clarias gariepinus (Siluriformes: Clariidae) in Brazil / Primeiro relato de metacercárias de Diplostomidae (Trematoda: Digenea) em bagre africano Clarias gariepinus (Siluriformes, Clariidae) no Brasil

Abstract Clarias gariepinus is a fish from North of South Africa and was later introduced in several countries, including Brazil. The present study aimed to describe the first report of Diplostomidae metacercariae in C. gariepinus in Brazil. For this, 30 C. gariepinus were captured in a lake in the city of Campos dos Goytacazes, RJ, Brazil. Fishes were euthanized using freezing and necropsied for collection of parasites. The organs were dissected and analyzed for the presence of parasites that were processed for light and scanning electron microscopy. Trematodes were stained with Semichon's Carmine and Gomori's Trichrome, observed and schematized under a light microscope with image analysis software. A total of 190 trematodes were collected from the gills, suprabranchial organs, heart, stomach, intestinal mesentery, liver and body cavity of the fish. The parasites had a foliaceous body divided by a discrete constriction, without genital primordia, and a holdfast organ present at the posterior region, typical of metacercariae of the family Diplostomidae. It was classified as the 'Diplostomulum' morphotype, based on the morphology of the reserve bladder structure. This is the first report of the metacercariae of Diplostomidae parasitizing C. gariepinus in the Americas. This fish acts as an intermediate or paratenic host of this digenean in Brazil.

Resumo Clarias gariepinus é um peixe do Norte da África do Sul e posteriormente introduzido em diversos países, incluindo o Brasil. O presente estudo teve como objetivo descrever o primeiro relato de metacercárias em C. gariepinus no Brasil. Para tanto, 30 C. gariepinus foram capturados em um lago na cidade de Campos dos Goytacazes, RJ, Brasil. Os peixes foram eutanasiados por congelamento e necropsiados para a coleta de parasitos. Os órgãos foram dissecados e analisados para a presença de parasitos que foram processados para microscopia ótica e electronica de varredura. Os Trematodeos foram corados com carmim de Semichon e tricrômico de Gomori, observados e esquematizados sob microscópio ótico equipado com software de análise de imagens. Um total de 190 trematodeos foram coletados das brânquias, órgãos suprabrânquiais, coração, estômago, mesentério intestinal, fígado e cavidade corporal dos peixes. Os parasitos tinham corpo foliáceo, dividido por uma discrete contrição, sem primórdio genital, e órgão tribocítico presente na região posterior, típico das metacercárias da fámilia Diplostomidae. Foram classificados como do morfotipo 'Diplostomulum', baseado na morfologia da estrutura da bexiga de reserva. Este é o primeiro relato de metacercárias de Diplostomidae parasitando C. gariepinus nas Américas. Este peixe atua como hospedeiro intermediário ou paratênico deste Digenea no Brasil.

Molecular identification and histological aspects of Renicola sloanei (Digenea: Renicolidae) in Puffinus puffinus (Procellariiformes): a first record / Identificação molecular e aspectos histológicos de Renicola sloanei (Digenea: Renicolidae) em Puffinus puffinus (Procellariiformes): primeiros registros

Abstract Renicolids are parasites that inhabit the renal tubules and ureters of molluscivorous and piscivorous birds. Puffinus puffinus is a migratory seabird that was identified as the definitive host of Renicola spp. Studies focusing on the renicolid species and the resulting renal lesions are valuable for their association with causes of stranding in seabirds. The aim of this study was to identify the renicolid trematodes and evaluate the histological findings in two P. puffinus stranded on the coast of Paraná state, Brazil. The parasites were evaluated by histologic, ultrastructural and molecular assays, while tissue changes were analyzed by histologic methods. The morphological and morphometrical characteristics of the parasites, along with polymerase chain reaction and sequencing assays (ribosomal and mitochondrial regions), identified the species as Renicola sloanei. The results also suggest that this helminth can be the adult form of Cercaria pythionike. The dilation of collecting ducts was the main histological finding in the kidneys. In conclusion, R. sloanei was identified, and for the first time, P. puffinus was described as a host of this digenean inducing mild renal changes.

Resumo Renicolídeos são parasitos que habitam túbulos renais e ureteres de aves que se alimentam de moluscos e peixes. Puffinus puffinus, ave marinha migratória, foi registrada como hospedeiro definitivo de Renicola spp. Estudos relacionados com as espécies de renicolídeos e as lesões renais resultantes são importantes para o entendimento das causas de óbito de aves marinhas. O objetivo deste estudo foi identificar os trematódeos renicolídeos e avaliar os achados histológicos em dois P. puffinus encalhados no litoral do Estado do Paraná, Brasil. Os parasitos foram avaliados por ensaios histológicos, ultraestruturais e moleculares, enquanto as alterações teciduais foram analisadas por métodos histológicos. As características morfológicas e morfométricas dos parasitos, juntamente com a reação em cadeia da polimerase e sequenciamento (regiões ribossomal e mitocondrial), identificaram a espécie como Renicola sloanei. Os resultados também sugerem que este helminto pode ser a forma adulta de Cercaria pythionike. A dilatação dos ductos coletores foi o principal achado histológico renal. Em conclusão, R. sloanei foi identificado, e pela primeira vez P. puffinus foi descrito como hospedeiro deste digenético induzindo alterações renais discretas.

Occurrence of Paratanaisia spp. Freitas, 1951 in a domiciled cockatiel (Nymphicus hollandicus, Psittaciformes: Cacatuidae) / Ocorrência de Paratanaisia spp. Freitas, 1951 em calopsita (Nymphicus hollandicus, Psittaciformes: Cacatuidae) domiciliada

Abstract Digenetic eucotylids of the Paratanaisia genus are widely reported parasites of the avian renal system. The infection, commonly reported in free-living and zoo-housed birds, is described for the first time in a domiciled bird, a cockatiel kept as pet bird with free access to the yard outdoors. The bird was received at Veterinary Hospital, where clinical and radiographic evaluations suggested a case of heavy-metal poisoning. Although the bird received supportive care and a chelating agent, it died the next day. The necropsy showed friable kidneys and congestion of blood vessels in structures such as the skin, proventriculus, brain, and skullcap. The histopathological evaluation of the kidneys revealed multifocal hemorrhages, commonly found in cases of heavy-metal poisoning. Parasitic structures similar to those of the digenean trematodes Paratanaisia spp. were also observed inside dilated collecting ducts, which presented epithelial cell flattening and vacuolization. There was compression of adjacent tissue and discrete fibrotic areas. In the presence of intermediate hosts in the yard, the synanthropic nature of some wild free-living birds could make them a source of trematodes infection and dissemination for pet birds. Conversely, the infected cockatiel could also have served as a reservoir and carrier of trematodes to wild free-living birds.

Resumo Eucotilídeos digenéticos do gênero Paratanaisia são amplamente descritos como parasitas do trato urinário de aves. A infecção, comumente relatada em aves de vida livre e em zoológicos, é descrita pela primeira vez em uma ave domiciliada, uma calopsita mantida como ave de companhia com livre acesso ao jardim externo. A ave foi recebida no Hospital Veterinário onde avaliações clínicas e radiográficas sugeriram um quadro de intoxicação por metal pesado. Embora tenha recebido tratamento de suporte e agente quelante a ave veio a óbito no dia seguinte. A necropsia demonstrou rins de consistência friável e congestão dos vasos sanguíneos da pele, proventrículo, cérebro e calota craniana. A avaliação histopatológica dos rins revelou hemorragias multifocais comumente observadas em intoxicação por metais pesados. Estruturas parasitárias similares àquelas observadas em Paratanaisia spp. foram observadas no interior de ductos coletores dilatados, os quais apresentavam achatamento e vacuolização de células epiteliais. Havia compressão do tecido adjacente e discretas áreas de fibrose. Na presença de hospedeiros intermediários no jardim, a condição sinantrópica de algumas aves de vida livre poderia torná-las fonte de infecção e disseminação de trematódeos para aves domiciliadas. Em contrapartida, a calopsita infectada poderia também servir como reservatório e carreador de trematódeos para aves de vida livre.

Light microscopy and surface topography of Urotrema scabridum and Renschetrema indicum (Digenea) from Rhinopoma hardwickii (Chiroptera): first report in Egypt / Microscopia de luz e topografia superficial de Urotrema scabridum e Renschetrema indicum (Digenea) de Rhinopoma hardwickii (Chiroptera): primeiro relato no Egito

Abstract This report introduced the description of two different species of digenean parasites isolated from the intestine of Rhinopoma hardwickii with new host and locality records in Egypt. The recovered helminthes were studied morphologically and morphometrically by light microscopy and the surface topography of the two species was elucidated by scanning electron microscopy (SEM). Urotrema scabridum had an elongated body, testes were tandem, ovaries were pretesticular, and vitelline follicles were observed in 2 lateral fields. SEM showed that the anterior half was covered with random and backwardly directed tegument spines. The lumen of the oral sucker was as a longitudinal slit encircled with type I dome-shaped papillae. The ventral sucker was wrinkled and covered by tongue-shaped tegument spines and several scattered papillae. Renschetrema indicum had a fusiform body with minute spines densely distributed in the anterior part of the body; testes sub-triangular, ovary fusiform; vitellaria were randomly distributed around the ceca and genital organs. SEM showed that the fore-body was ventrally concave and surrounded by cytoplasmic ridges equipped with numerous closely packed claw-shaped spines. The oral sucker was externally surrounded by two circles of papillae while the lip of the ventral sucker was rounded and surrounded by three papillae located in its upper end and anterolaterally.

Resumo O trabalho descreve duas espécies diferentes de parasitas digêneos isolados do intestino de Rhinopoma hardwickii, com novos registros de hospedeiros e localidade no Egito. Os helmintos recuperados foram estudados morfologicamente e morfometricamente por microscopia óptica, e a topografia superficial das duas espécies foi verificada por microscopia eletrônica de varredura (MEV). Urotrema scabridum apresenta um corpo alongado, testículos em tandem, ovários localizados pré-testiculares e os folículos vitelinos foram observados em 2 campos laterais. A microscopia eletrônica (ME) mostrou que a metade anterior do tegumento estava coberta com espinhos aleatoriamente e voltados para trás. O lúmen da ventosa oral apresentava-se como uma fenda longitudinal cercada de papilas em forma de cúpula tipo I. A ventosa ventral estava enrrugada e coberta por espinhos no tegumento em forma de língua e com várias papilas dispersas. Renschetrema indicum tinha um corpo fusiforme com espinhos diminutos densamente distribuídos na parte anterior do corpo; testículos sub-triangulares, ovários fusiformes; as glândulas vitelínicas estavam distribuídas aleatoriamente em torno do ceco e dos órgãos genitais. À ME a região anterior mostrou-se ventralmente côncava e cercada por cristas citoplasmáticas equipadas com numerosos espinhos em forma de unhas muito próximos. A ventosa oral apresentou-se externamente cercada por duas fileiras de papilas, enquanto a borda da ventosa ventral mostrou-se arredondada e cercada por três papilas localizadas na sua extremidade superior e antero-lateralmente.

Molecular Description of Macroorchis spinulosus (Digenea: Nanophyetidae) Based on ITS1 Sequences

We performed a molecular genetic study on the sequences of 18S ribosomal RNA (ITS1 region) gene in 4-day-old adult worms of Macroorchis spinulosus recovered in mice experimentally infected with metacercariae from crayfish in Jeollanam-do Province, Korea. The metacercariae were round, 180 µm in average diameter, encysted with 2 layers of thick walls, but the stylet on the oral sucker was not clearly seen. The adult flukes were oval shape, and 760-820 µm long and 320-450 µm wide, with anterolateral location of 2 large testes. The phylogenetic tree based on ITS1 sequences of 6 M. spinulosus samples showed their distinguished position from other trematode species in GenBank. The most closely resembled group was Paragonimus spp. which also take crayfish or crabs as the second intermediate host. The present study is the first molecular characterization of M. spinulosus and provided a basis for further phylogenetic studies to compare with other trematode fauna in Korea.

First record of Palombitrema triangulum (Suriano, 1981) Suriano, 1997 (Monogenea: Dactylogyridae) from freshwater fishes in Brazil / Primeiro registro de Palombitrema triangulum (Suriano, 1981) Suriano, 1997 (Monogenea: Dactylogyridae) de peixes dulcícolas do Brasil

This study reports for the first time the monogenean Palombitrema triangulum Suriano (1981) in freshwater fishes from Brazil, highlighting new sites of infection for this helminth and some morphological differences. Monogeneans were collected on the body surface, gills and nasal cavity of two native fish species from Brazil, Cyphocharax modestus (Fernández-Yépez, 1948) and Cyphocharax nagelii (Steindachner, 1881). A brief morphological characterization of this species is presented.

Descreve-se a primeira ocorrência do monogenético Palombitrema triangulum Suriano (1981) em peixes dulcícolas do Brasil, destacando novos locais de infestação para este helminto e algumas diferenças morfológicas. Os monogenéticos foram coletados na superfície do corpo, brânquias e cavidade nasal de duas espécies de peixes nativos do Brasil, Cyphocharax modestus (Fernández-Yépez, 1948) e Cyphocharax nagelii (Steindachner, 1881). Uma breve caracterização morfológica desta espécie é apresentada.

Infection Status of Zoonotic Trematode Metacercariae in Fishes from Vientiane Municipality and Champasak Province in Lao PDR

The infection status of fishborne zoonotic trematode (FZT) metacercariae was investigated in fishes from 2 localities of Lao PDR. Total 157 freshwater fishes (17 species) were collected in local markets of Vientiane Municipality and Champasak Province in December 2010 and July 2011, and each fish was examined by the artificial digestion method. Total 6 species of FZT metacercariae, i.e., Opisthorchis viverrini, Haplorchis taichui, Haplorchis yokogawai, Haplorchis pumilio, Centrocestus formosanus, and Procerovum varium, were detected in fishes from Vientiane Municipality. The metacercariae of O. viverrini were detected in 50 (49.5%) out of 101 fishes (6 species), and their average number was 154 per fish infected. The remaining 5 species of heterophyid metacercariae were detected in 36.8%, 65.8%, 9.4%, 23.9%, and 5.1% fishes examined, and their average densities were 12, 1,038, 4, 15, and 13 per infected fish, respectively. In fishes from Champasak Province, 3 species of FZT metacercariae, i.e., O. viverrini, H. taichui, and H. yokogawai, were detected. Only 2 O. viverrini metacercariae were found in only 1 Barbonymus schwanefeldi. The metacercariae of H. taichui and H. yokogawai were detected in 60.0% and 50.0% of fishes examined, and their average densities were 47 and 28 per fish infected. By the present study, it has been confirmed that several species of FZT metacercariae are prevalent in fishes from Vientiane Municipality, with P. varium being a new member of FZT in Lao PDR. In comparison, FZT metacercariae are less prevalent in fishes from Champasak Province.

Serine Proteases of Parasitic Helminths

Serine proteases form one of the most important families of enzymes and perform significant functions in a broad range of biological processes, such as intra- and extracellular protein metabolism, digestion, blood coagulation, regulation of development, and fertilization. A number of serine proteases have been identified in parasitic helminths that have putative roles in parasite development and nutrition, host tissues and cell invasion, anticoagulation, and immune evasion. In this review, we described the serine proteases that have been identified in parasitic helminths, including nematodes (Trichinella spiralis, T. pseudospiralis, Trichuris muris, Anisakis simplex, Ascaris suum, Onchocerca volvulus, O. lienalis, Brugia malayi, Ancylostoma caninum, and Steinernema carpocapsae), cestodes (Spirometra mansoni, Echinococcus granulosus, and Schistocephalus solidus), and trematodes (Fasciola hepatica, F. gigantica, and Schistosoma mansoni). Moreover, the possible biological functions of these serine proteases in the endogenous biological phenomena of these parasites and in the host-parasite interaction were also discussed.

Zoonotic Intestinal Trematodes in Stray Cats (Felis catus) from Riverside Areas of the Republic of Korea

The present study was performed to survey the infection status of zoonotic intestinal trematode (ZIT) in stray cats from 5 major riverside areas in the Republic of Korea. Total 400 stray cats were captured with live-traps in riverside areas of Seomjingang (\'gang' means river) (203 cats) from June to October 2010, and of Yeongsangang (41), Nakdonggang (57), Geumgang (38), and Hangang (61 cats) from June to October 2011, respectively. Small intestines resected from cats were opened with a pair of scissors in a beaker with 0.85% saline and examined with naked eyes and under a stereomicroscope. More than 16 ZIT species were detected in 188 (92.6%) cats from Seomjingang areas, and the number of worms recovered was 111 per cat infected. In cats from riverside areas of Yeongsangang, Nakdonggang, Geumgang, and Hangang, more than 9, 8, 3, and 5 ZIT species were recovered, and the worm burdens were 13, 42, 11, and 56 specimens per infected cat, respectively. As the members of family Heterophyidae, more than 10 species, i.e., Metagonimus spp., Pygidiopsis summa, Heterophyes nocens, Stellantchasmus falcatus, Heterophyopsis continua, Acanthotrema felis, Centrocestus armatus, Procerovum varium, Cryptocotyle concava, and Stictodora lari, were recovered. More than 5 species of echinostomes, i.e., Echinostoma hortense, Echinochasmus japonicus, Echinochasmus sp., Echinoparyphium sp., and unidentified larval echinostomes, were collected. Plagiorchis spp. were detected in cats from areas of Seomjin-gang and Yeongsangang. From the above results, it has been confirmed that stray cats in 5 major riverside areas of Korea are highly infected with various species of ZITs.

Potential Zoonotic Trematodes Recovered in Stray Cats from Kuwait Municipality, Kuwait

Stray cats are a common feature roaming the streets and alleys of Kuwait; they could be a source of parasites, including trematodes, that affect humans. A survey was conducted to identify feline trematodes and throw the light on their public health significance in Kuwait. Out of 240 stray cats trapped from different localities of Kuwait from June 2011 to May 2012, 59 (24.6%) were found to be infected with 14 species of trematodes. The most common were trematodes of the genus Heterophyes, particularly H. heterophyes and H. dispar that were found in respectively 15.8% and 10.8% of the cats examined. Other trematodes recorded, with lower prevalences, were Heterophyes nocens (2.9%), Haplorchis taichui (3.8%), Stictodora sawakinensis (2.1%), Stellantchasmus falcatus (1.6%), Echinochasmus japonicus (1.6%), and Mesostephanus dottrensi (1.3%). Centrocestus cuspidatus, Galactosomum fregatae, Ascocotyle sp., Mesostephanus appendiculatus, Haplorchis yokogawai, and Pygidiopsis genata showed the lowest prevalence (0.4%) and intensity. The majority of the trematodes are recorded for the first time in Kuwait and even in the Gulf region. The study reveals that stray cats are good indicators of fish-borne trematodes in the environment. As all trematodes recovered are zoonotic, their significance to public health should be considred.

Trematode Metacercariae in Freshwater Fish from Water Systems of Hantangang and Imjingang in Republic of Korea

The infection status of freshwater fish with digenetic trematode metacercariae was examined in water systems of Hantangang and Imjingang (River), the Republic of Korea. A total of 877 (594 from Hantangang and 283 from Imjingang) fishes were examined by the artificial digestion methods. Clonorchis sinensis metacercariae were detected in 7 (1.2%) fishes (in 3 spp.) from Hantangang in Cheorwon-gun, Gangwon-do, and 40 (14.1%) fishes (in 7 spp.) from Munsancheon in Paju-si, Gyeonggi-do. The average densities were 1.9 and 35.6 per fish infected, respectively. Metagonimus spp. metacercariae were detected in 312 (52.5%) and 113 (39.9%) fishes from Hantangang and Imjingang, and their average densities were 47.5 and 9.6 per fish infected, respectively. Centrocestus armatus metacercariae were found in 161 (27.1%) and 70 (24.7%) fishes from Hantangang and Imjingang, and their average number per fish infected was 694 and 82, respectively. Echinostoma spp. metacercariae were detected in 50 (8.4%) and 94 (33.2%) fishes from Hantangang and Imjingang, and their average densities were 9.6 and 23.1 per fish infected, respectively. The infection status of fishes with metacercariae of Stephanoprora spp., Diplostomum spp., Clinostomum complanatum, Metorchis orientalis, and Metorchis taiwanensis were analyzed by surveyed regions. Conclusively, it was confirmed that C. sinensis metacercariae were quite commonly detected in fishes from Munsancheon but rarely from other localities, whereas the metacercariae of other digenetic trematodes were relatively prevalent in fishes from water systems of Hantangang and Imjingang in Korea.

Haematological and histopathological analysis in South American fish Piaractus mesopotamicus parasitized by monogenean (Dactylogyridae) / Análises hematológica e histopatológica no peixe sul-americano Piaractus mesopotamicus parasitado por Monogenea (Dactylogyridae)

Monogeneans are the parasites mostly found on the body surface and gills of fish and can cause large losses in farmed fish. Some studies demonstrate elevated parasitic levels causing hematological alterations. But few of them relate the effects of parasitism on the hematology and histopathology of native freshwater farmed fish. This study evaluated the host-parasite relationship in pacu (Piaractus mesopotamicus) parasitized by the monogenean Anacanthorus penilabiatus. Hematological and parasitological assessments were obtained in 60 fish captured in a fish farm located in Dourados, State of Mato Grosso do Sul, Central Brazil. Fish were analyzed in different categories of parasite number: class I (n=13; 0-200 parasites), class II (n=17; 201-1200 parasites); class III (n=7; 1201-2200 parasites); and class IV (n=23; more than 2200 parasites per host). The highest levels of parasitism caused significant decrease (p<0.05) in the hematocrit, red blood cells (RBC), mean hemoglobin concentration (MCHC) and basophils number. Thrombocytes, mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), monocytes, eosinophils, neutrophils and LG-PAS did not present significant difference among the parasitic levels. In contrast, increased number of total leukocytes and lymphocytes were found in highly-parasitized fish. A positive linear correlation (p<0.01) was found between the amount of parasites and fish weight. Histopathology revealed severe hyperplasia, sub-epithelial edema, fusion of the secondary lamellae, focal and multifocal necrosis in highly parasitized fish.

Parasitos Monogenea são principalmente encontrados na superficie corporal e brânquias dos peixes, e podem acarretar grandes perdas em pisciculturas. Alguns estudos demonstram que elevados níveis de infestação parasitária podem alterar os parâmetros sanguíneos. Porém, poucos estudos se direcionam a esclarecer os efeitos do parasitismo sobre as características hematológicas em peixes nativos. Este estudo avaliou a relação parasito-hospedeiro em pacu (Piaractus mesopotamicus) parasitado pelo monogenético Anacanthorus penilabiatus. Avaliações hematológicas e parasitológicas foram obtidas de 60 peixes capturados de uma piscicultura localizada em Dourados, Estado de Mato Grosso do Sul (MS), Brasil Central. Os peixes foram divididos em diferentes categorias de número de parasitos: classe I (n=13; 0-200 parasitos), classe II (n=17; 201-1200 parasitos); classe III (n=7; 1201-2200 parasitos); e classe IV (n=23; mais que 2200 parasitos por hospedeiro). Os níveis mais elevados de parasitismo causaram diminuição significativa (p<0.05) no hematócrito, eritrócitos (RBC), concentração de hemoglobina corpuscular média (CHCM) e número de basófilos. Trombócitos, volume corpuscular médio (VCM), concentração de hemoglobina corpuscular media (CHCM), monócitos, eosinófilos, neutrófilos e LG-AS não apresentaram diferença significativa entre os níveis de parasitismo. Em contraste, o aumento do número de leucócitos totais e linfócitos foram encontrados em peixes altamente parasitados. Houve correlação linear positiva entre a quantidade de parasitos e o peso dos peixes. O exame histopatológico revelou severa hiperplasia, edema sub-epitelial, fusão das lamelas secundárias, necroses focal e multifocal em peixes altamente parasitados.

Helicometrina nimia Linton, 1910 (Digenea: Opecoelidae) in dusky grouper Epinephelus marginatus (Lowe, 1834) (Teleostei: Serranidae) from southeastern Brazil / Helicometrina nimia Linton, 1910 (Digenea: Opecoelidae) em garoupa verdadeira Epinephelus marginatus (Lowe, 1834) (Teleostei: Serranidae) no Sudeste do Brasil

Helicometrina nimia (Opecoelidae) is a digenean with wide distribution. Fish families most commonly used as hosts for H. nimia are Serranidae, Pomodasydae, Scorpaenidae and Clinidae. In the present study, a new host and a new host locality are presented for the species. A description of the studied specimens, besides comments concerning its taxonomic status and biometrically compared tables of H. nimia reports are given. The taxonomic status of members of Helicometrina has been questionable. The greatest controversy for the genus seems to be related to the validity of diagnostic features, especially in regard to the number of testes. In the present study, all studied specimens presented a permanent and steady number of testes (n=9) and therefore its use as a diagnostic character is supported by the present authors. Epinephelus marginatus is considered a new host for Helicometrina nimia, and São Paulo state, southeastern Brazil, a new locality for the species.

Helicometrina nimia (Opecoelidae) é um digenético com distribuição mundial. As famílias de peixes mais comumente utilizadas como hospedeiros por H. nimia são Serranidae, Pomodasydae, Scorpaenidae e Clinidae. No presente estudo, um novo hospedeiro e uma nova localidade são apresentados para a espécie. A descrição dos espécimes estudados, além de comentários sobre o seu status taxonômico e uma tabela comparativa de medidas de H. nimia são apresentados. O status taxonômico dos membros de Helicometrina tem sido questionável. A maior controvérsia dentro do gênero parece estar relacionada com a validade das características diagnósticas, especialmente no que diz respeito ao número de testículos. No presente estudo, todos os espécimes estudados apresentaram número permanente e estável de testículos (n=9) e, portanto, sua utilização como caráter diagnóstico é suportada pelos presentes autores. Epinephelus marginatus é considerada um novo hospedeiro para Helicometrina nimia e São Paulo, sudeste do Brasil, uma nova localidade para a espécie.

Zoonotic Trematode Metacercariae in Fish from Phnom Penh and Pursat, Cambodia

A survey was performed to investigate the infection status of freshwater fish with zoonotic trematode metacercariae in Phnom Penh and Pursat Province, Cambodia. All collected fish with ice were transferred to our laboratory and examined using the artificial digestion method. In fish from Phnom Penh, 2 kinds of metacercariae (Opisthorchis viverrini and Haplorchis yokogawai) were detected. O. viverrini metacercariae were positive in 37 (50.0%) of 74 fish in 11 species (average no. metacercariae/fish, 18.6). H. yokogawai metacercariae were detected in 23 (57.5%) of 40 fish in 5 species (average no. metacercariae/fish, 21.0). In fish from Pursat Province, 5 kinds of metacercariae (O. viverrini, H. yokogawai, Haplorchis pumilio, Centrocestus formosanus, and Procerovum sp.) were detected; O. viverrini metacercariae (n=3) in 2 fish species (Henicorhynchus lineatus and Puntioplites falcifer), H. yokogawai metacercariae (n=51) in 1 species (P. falcifer), H. pumilio metacercariae (n=476) in 2 species (H. lineatus and Pristolepis fasciata), C. formosanus metacercariae (n=1) in 1 species (H. lineatus), and Procerovum sp. metacercariae (n=63) in 1 species (Anabas testudineus). From the above results, it has been confirmed that various freshwater fish play the role of a second intermediate host for zoonotic trematodes (O. viverrini, H. yokogawai, H. pumilio, C. formosanus, and Procerovum sp.) in Cambodia.