Abstract: Two species of nematodes belonging to the genus Ichthyouris Inglis, 1962 (I. ro and I. bursata), were collected from the cichlid fish Mesonauta festivus in the central Brazilian Amazon region. Both species are reported in this locality for the first time. I. bursata is reported in a new host, M. festivus, and this is the first report of I. ro parasitizing its type host in Brazil. We provide a more detailed description for I. ro, including morphological aspects that were not mentioned in the original description.

Resumen: Se recolectaron 2 especies de nemátodos pertenecientes al género Ichthyouris Inglis, 1962, I. ro e I. bursata, del pez cíclido Mesonauta festivus en el centro de la Amazonía brasileña. Ambas especies se reportan por primera vez en esta localidad. I. bursata se registra en un nuevo hospedero, M. festivus, y éste es el primer informe de I. ro parasitando a su hospedero tipo en Brasil. Se da una descripción detallada de I. ro, incluyendo aspectos morfológicos que no fueron mencionados en la descripción original.

During a survey of the helminth parasites of Ctenosciaena gracilicirrhus from the Atlantic Ocean, off Angra dos Reis, Rio de Janeiro State, Brazil, 10 species of metazoan parasites were collected: 1 species of Monogenea (Choricotyle rohdei); 3 species of Nematoda (Hysterothylacium sp. third stage larvae, Raphidascaris sp. third stage larvae, and Procamallanus (Spirocamallanus) pereirai third and fourth stages larvae and adults); 6 species of Digenea (Opecoeloides pedicathedrae, Opecoeloides melanopteri, Diplomonorchis leiostomi, Aponurus laguncula, Parahemiurus merus and Manteriella sp.). Choricotyle rohdei and Hysterothylacium sp. had the highest prevalence, mean intensity and abundance and an aggregated pattern of distribution was observed in both species. A positive correlation between the standard length of hosts and the parasitic abundance of Hysterothylacium sp. and C. rohdei was observed. The prevalence of C. rohdei was positively correlated with standard length of the host, while in Hysterothylacium sp. there was no correlation. Ctenosciaena gracilicirrhus represents a new host record to all species of Nematoda and Digenea presented herein. The genus Manteriella is reported for the first time in South America.

Durante un estudio de los helmintos de Ctenosciaena gracilicirrhus de la zona costera de Angra dos Reis, Rio de Janeiro, Brasil, 10 especies de parásitos metazoos fueron recolectados: 1 especie de Monogenea (Choricotyle rohdei); 6 de Digenea (Opecoeloides pedicathedrae, Opecoeloides melanopteri, Diplomonorchis leiostomi, Aponurus laguncula, Parahemiurus merus y Manteriella sp.); 3 nemátodos (Hysterothylacium sp. y Raphidascaris sp., ambas larvas de tercer estadio y Procamallanus (Spirocamallanus) pereira, larvas de tercer y cuarto estadios y adultos). Choricotyle rohdei y Hysterothylacium sp. presentaron la mayor prevalencia, intensidad media y abundancia, así como un patrón agregado de distribución. Se observó una correlación positiva entre la longitud estándar de los hospederos y la abundancia parasitaria de Hysterothylacium sp. y C. rohdei. La prevalencia de Choricotyle rohdei se relaciona positivamente con la longitud estándar del huésped, mientras que en Hysterothylacium sp., no hubo correlación. Ctenosciaena gracilicirrhus representa un nuevo registro de huésped para todas las especies de Digenea y Nematoda registrados en este trabajo. El género Manteriella se registra por primera vez en América del Sur.

Tormopsolus brasiliensis sp. nov. is described from the intestine of Genypterus brasiliensis Regan, 1903, from Brazil. The new species is characterized mainly by having an almost square terminal oral sucker, a pharynx of the same size or larger than the oral sucker, and testes very close to each other and without vitelline follicles between them. Tormopsolus brasiliensis sp. nov. is most closely related to T. lintoni Caballero, 1952, sharing with the latter the space between the gonads and the distribution of the vitelline fields. It differs from that species by the lack of a space between the gonads and the absence of vitelline follicles between the testes; by the smaller distance between the oral and ventral suckers; by the presence of a wide ejaculatory duct armed with spines; a wide metraterm, almost the same size of the cirrus-sac; and by the shape and terminal position of the oral sucker. Specimens recovered already dead showed distinct differences to the well-fixed, freshly-collected material and are these differences are enumerated. Acanthocolpus brasiliensis of ALVES et al. (2002a,b) is considered synonym of T. brasiliensis sp. nov.

Cinquenta e quatro espécimens de peixes marinhos pertencentes a sete espécies coletados do litoral do estado do Rio de Janeiro, Brasil foram examinados para helmintos, os resultados referentes a Monogenea e Digenea são apresentados. Os monogenéticos Metamicrocotyla macracantha, Microcotyle pomatomi e Gotocotyla acanthura são apresentados em novos hospedeiros. Os digenéticos Parahemiurus merus, Lecithochirium microstomum, Gonocercella pacifica, Aponurus laguncula, Gonocerca trematomi e Lampritrema miescheri são registrados em novos hospedeiros, as duas últimas espécies são também registradas pela primeira vez no Brasil.

Fifty four specimens of marine fish belonging to seven species collected from the coast of the State of Rio de Janeiro, Brazil were examined for helminths, and results relating to Monogenea and Digenea are presented. The monogeneans Metamicrocotyla macracantha, Microcotyle pomatomi and Gotocotyla acanthura are reported in new hosts. The digeneans Parahemiurus merus, Lecithochirium microstomum, Gonocercella pacifica, Aponurus laguncula, Gonocerca trematomi and Lampritrema miescheri are reported in new hosts, and the latter two species are also reported for the first time in Brazil.

O trematódeo digenético Psilochasmus oxyurus (Creplin, 1835) Lühe, 1909, embora de ampla distribuição geográfica, é referido em gansos (Anser anser Linnaeus, 1758) pela primeira vez na América do Sul, com base em espécimes coletados em gansos domésticos no Brasil, com prevalência de 20%. Dados morfométricos gerais dos parasitos são incluídos. Não foram observados sinais clínicos, macro lesões ou alterações histopatológicas nas aves.

The digenetic trematode Psilochasmus oxyurus (Creplin, 1835) Lühe, 1909, although with a large geographical distribution, is referred in geese (Anser anser Linnaeus, 1758) for the first time in South America, on the basis of specimens parasitizing Brazilian domestic geese, with a prevalence of 20%. Brief morphometric data on the parasites are included. Clinical signs, gross and microscopic lesions were not observed in the birds.

Rhipidocotyle gibsoni n.sp. is described from Acestrorhynchus lacustris from Paraná River, brazil. It is most closely related to r. froesi n. sp. and to R. eckmanni in the shape of the cephalic hood, differing in the extent of the uterus, in the position of the vitelline follicles and in that the host is a freshwater fish. Rhipidocotyle froesi n. sp. is proposed for the marine specimens described by Eckmann (1932) as R. baculum (Linton, 1905).

Macvicaria crassigula (Linton, 1910) (Opecoelidae) is referred from the intestine of Micropogonias furnieri and from Stellifer rastrifer; and from Stellifer rastrifer, and Saturnius maurepasi Overstreet, 1977 (Bunocotylidae) from the stomach of Mugil liza. This is the first report of these species in Brazil, and a new host records are presented.

Dinosoma clupeola sp. n. é descrito de Harengula clupeola, e assemelha-se a D. hawaiiense Yamaguti, 1970, da qual difere pela vesícula seminal que é inteira, sacular alongada, e não signóide e torcida em duas ou três porções, pelo tegumento que é fracamente plicado, e não liso, pelo meneor tamanho do corpo e dos órgãos internos e pelos ovos que são ligeiramente maiores e mais estreitos. Pseudoacanthostomum floridensis Nahhas & Shsort, 1965 é referido em um novo hospedeiro: Netuma barba.

Dinosoma clupeola sp. n. is described from Harengula clupeola, and resembles D. hawaiiense Yamaguti, 1970, from which it differs in the entire, elongate-saccular seminal vesicle, tegument weakly plicated, smaller size of body and internal organs, and slightly larger and narrower eggs. Pseudoacanthostomum floridensis Nahhas & Short, 1965 is referred to Netuma barba, which represents a new host record.

Schikhobalotrema solitaria sp. n. is described from Stephanolepis hispidus (Linnaeus, 1758), and is characterized by the relation between oral sucker and pharynx 1:1,1. This Relation in the other species ranges between 1:0.3-0.6. It is more similar to S. manteri Siddiqi & Cable, 1960 in the distribution of vitellaria, differing from it in the size of vitelline follicles, extension of uterus and in the size of the eggs. S. acanthuri Yamaguti, 1970 is referred for the first time in South America in Mugil liza Valenciennes, 1836 representing a new host record.

São descritos Procamallanus petterae n. sp. paradito de Plecostomus albopunctatus e Spirocamallanus pintoi n. sp. de Corydors paleatus. P. petterae diferencia-se das demais espécies do gênero por apresentar cápsula bucal sem estrias, com cinco estruturas em forma de dentes na base e quatro estruturas em forma de placas próximo da margem anterior; relação do comprimento do esôfago muscular/glandular 1:1,4; espículos curtos com 21 e 16 µm de comprimento respectivamente e terminação caudal afilando-se abruptamente e terminando em ponta, em ambos os sexos. S. pintoi n. sp. caracteriza-se por possuir cápsula bucal com 6 a 8 espirais no macho e 9 a 10 na fêmea, ocupando somente 2/3 do comprimento da cápsula; comprimento do esôfago glandular mais de duas vezes o muscular e espículos curtos, direito medindo 94 µm e esquerdo 82 µm de comprimento. S. pintoi n. sp. é mais próxima de S. hilarii (Vaz & Pereira, 1934) e de S. incarocai (Freitas & Ibanez, 1970), das quais se diferencia principalmente pelo menor número de espirais na cápsula bucal.

Procamallanus petterae n. sp. from Plecostomus albopunctarus and Spirocamallanus pintoi n. sp. from Corydoras paleatus are described. procamallanus petterae n. sp. differs from all other species of the genus by having a buccal capsule without spiral bands, with five teeth-like structures on its base and four plate-like structures near the anterior margin; length ratio of oesophagus muscular/glandular 1:1.4; spicules short, 21µ m and 16µ m long and tails ending abruptly in a sharp point, in both sexes. Spirocamallanus pintoi n. sp. is characterized by having 6 to 8 spiral thickenings in the buccal capsule of male and 9 to 10 in female, occupying 2/3 of the length of the capsule; length of glandular oesophagus more than twice the muscular; spicules short, the right 94µ m and the left 82µ m long.

Na Usina Hidrelátrica Salto Osório foram examinados 88 peixes, dos quais 24 (27,3%) encontravam-se parasitados por oito espécies de nematóides: Capillaria sp., formas imaturas de Contracoecum sp., Procamallanus peraccuratus Pinto et al., 1976, Procamallanus petterae Kohn & Fernandes, 1988, Raphidascaris sp., Spirocamallanus intermedius Pinto et al., 1974, Spirocamallanus pintoi Kohn & Fernandes, 1988 e Spirocamallanus sp., além de uma forma imatura de cestóide. Na Usina Hidrelétrica de Salto Santiago, dos 83 peixes examinados, 32 (38,5%) apresentaram-se parasitados por três espécies de nematóides: Contracoecum sp. (forma larvar), Procamallanus peraccuratus e Raphydascaris sp., e uma especie de cestóide (forma larvar).

Eight species of nematodes and one larval cestode were recovered from 88 specimens of 12 species of fishes captured in the reservoir of "Salto Osório". Capillaria sp., Contracoecum sp., (larval forms), Procamallanus peraccuratus pinto et al., 1976, Procamallanus petterae Kohn & Fernandes, 1988, Raphidascaris sp., Spirocamallanus intermedius Pinto et al., 1974 and Spirocamallanus pintoi Kohn & Fernandes, 1988. From 83 specimens of 12 species of fishes from the reservoir of "Salto Santiago", only one species of cestode and three species of nematodes were recovered: Contracoecum sp. (larval forms), procamallanus peraccuratus and Raphidascaris sp. Pimelodus ortmanni is a new host record for P. peraccurants and S. intermedius.

Este trabalho abrange o parasitismo por nematóides, acantocéfalos, trematódeos e cestóides de 1027 peixes pertencentes a 45 espécies do rio Mogi Guassu, examinados nos anos de 1927, 1946, 1947, 1962, 1983 e 1985, como uma contribuição ao conhecimento da fauna parasitária em 58 anos. São relacionadas 32 espécies de nematóides, 21 de trematódeos, três de acantocéfalos e duas de cestóides. São referidos novos hospedeiros para Cucullanus pinnai, Spirocamallanus inopinatus e Travnema travnema, para o trematódeo Pararhipidocotyle jeffersoni e para o acantocéfalo Gorytocephalus spectabilis. São apresentadas medidas adicionais de Creptotrema lynchi, tabelas, gráficos e a lista dos hospedeiros examinados e seus parasitos.

This paper concerns the parasitism of Nematoda, Trematoda, Acanthocephala and Cestoda from 1027 fishes of 45 species from Mogi Guassu river, examined in the years 1927, 1946, 1947, 1962, 1983 and 1985 as a contribution to the knowledge of the parasitological fauna in 58 years. Thirty two species of nematodes, 21 of trematodes, 3 of acanthocephalans and 2 of cestodes are reported. New hosts are presented for the nematodes Cucullanus pinnai, Spirocamallanus inopinatus and Travnema travnema, for the trematode Pararhipidocotyle jeffersoni and for the acanthocephalan Gorytocephalus spectabilis. New measurements for the trematode Creptotrema lynchy, tables, graphics and a list of the examined hosts with their parasites are presented.