Urocleidoides astyanacis n. sp. (Mongenva ancyrocephalinae) from frescwater characidians on the genus Astyanax

A new species of Urocleidoides, U. astyanacis (Monogenea, Ancyrocephalinae) is described from the "lambari" Astyanax scabripinnis (Jenyns, 1842) and A. fasciatus (Cuvier, 1819). Hosts were collected in Atibaia and Jaguari Rivers near Campinas, São Paulo State, Brazil.

Neotropical Monogenoidea. 24. Rhinoxenus bulbovaginatus n. sp. (Dactylogyridae, Ancyrocephalinae) from the nasal cavity of Salminus maxillosus (Osteichthyes, Characidae) from the Rio Paraná, Paraná, Brazil

Rhinoxenus bulbovaginatus n. sp. is described from the nose of Salminus maxillosus (Characidae) collected in the basin of the rio Paraná, near the city of Porto Rico, state of Paraná, Brazil. The new species can be differentiated from the other three species in the genus by the morphology of the copulatory complex, vagina, and ventral anchor. The sister group relationship of the known species of Rhinoxenus was determined using techniques of Phylogenetic Systematics (Cladism). The resulting cladogram (C.I.=100%) indicates that the new species is most closely related to R. piranhus Kritsky, Boeger and Thatcher, 1988. The other two species of the genus, R. arietinus Kritsky, Boeger and Thatcher, 1988 and R. nyttus Kritsky, Boeger and Thatcher, 1988, both parasites of Anostomidae fishes, have a paraphyletic position in the cladogram, suggesting that the origin of at least one of them can not be associated to cospeciation.

A New Species of Kritskyia (Dactylogyridae, Ancyrocephalinae) Parasite of Urinary Bladder of Prochilodus lineatus (Prochilodontidae, Characiformes) from the Floodplain of the High Paraná River, Brazil

A new species of Kritskyia inhabits the urinary bladder of the "curimba", Prochilodus lineatus in the floodplain of the high Paraná river. The new species resembles others members of Kritskyia in the following features: haptor lacking anchors and with 14 hooks marginal, posterior male copulatory organ non articulated with the accessory piece and vagina a sclerotized tube. However, it differs from the known species mainly by the shape of the copulatory complex. This is the third endoparasitic monogenean species reported from freshwater Neotropical fish.

Unilatus unilatus Mizelle & Kritsky, 1967 (Monogenea, Ancyrocephalinae) in Hypostomus spp. (Siluriformes, Loricariidae) from the Chavantes reservoir, So Paulo State, Brazil

In this paper, the occurrence and new morphological data of Unilatus unilatus Mizelle et Kritsky, 1967 from the gills of Hypostomus strigaticeps (Regan, 1907), Hypostomus regani (Ihering, 1905), and Hypostomus iheringii (Regan, 1908) from the Chavantes reservoir, So Paulo State, Brazil are reported. Unilatus unilatus from this reservoir presents differences in relation to the holotype previously described such as, eggs with no bifid or trifid filament and a rounded termination, anterior bar slightly curved with a posterior projection, and posterior bar which may present three shapes. This is the first record of U. unilatus in southeastern Brazil outside the Amazon River Basin, with H. strigaticeps, H. regani and H. iheringii as new hosts.

Haliotrema (Monogenea: Ancyrocephalinae) from Ostraciid Fishes in Guadeloupe, West Indies

Six sympatric species of Haliotrema Johnston and Tiegs, 1922 are described from ostraciid fishes in Guadeloupe, West Indies. All have a basic cone-shaped cirrus, but characteristics of that and other terminal genitalia plus those of anchors can differentiate them: H. guadeloupensis sp. n. from Lactophrys triqueter (typehost) and L. bicaudalis; H. torridum sp. n. from L. triqueter (type-host) and Acanthostracion polygonius; H. glandulosum sp. n. from L. triqueter (type-host) and L. bicaudalis; H. minutum sp. n. from A. polygonius; H. lactophrys (MacCallum, 1915) comb. n. from A. polygonius and A. quadricornis which is transferred from the genus Ancyrocephalus Creplin, 1839; and H. kritskyi nom. nov. from A. polygonius. The latter has been given a replacement name for Parahaliotrema brevis. Mizelle and Kritsky, 1969 which would become a junior homonym because it, H. affinis (Mizelle and Kritsky, 1969) comb. n., H. cornutus (M. and K.) comb. n., H. grandis (M. and K.) comb. n., H. pacificus (M. and K.) comb. n., and H. zebrasoma (M. and K.) comb. n. are all transferred from the genus Parahaliotrema Mizelle and Price, 1964. We follow others in considering that genus to be a junior synonym of Haliotrema. We also determined that at least Ancyrocephalus parupenei Yamaguti, 1968 and A. pauu Yamaguti, 1968 do not belong in Ancyrocephalus. However, investigation of H. australe Johnston and Tiegs, 1922 and other species should precede transferring those species to another genus.

Occurrence of Sciadicleithrum mexicanum Kritsky, Vidal-Martinez et Rodríguez-Canul, 1994 (Monogenea: Dactylogyridae) in the Cichlid Cichlasoma urophthalmus from a flooded quarry in Yucatan, Mexico

Cichlids, Cichlasoma urophthalmus, collected in a flooded quarry in the Yucatan Peninsula, Mexico, from January through June 1992, had high levels of infection with the ancyrocephaline Sciadicleithrum mexicanum (Monogena: Dactylogyridade) in all montlhly samples. Neither occurrence nor maturation of the worms eshibited any pronounced monthly fluctuation. The infection rate was found to be sizedependent, greater in longer fish. The worms occurred on primary lamellae of gill filaments of all arches, with lower numbers of parasites attached to the fourth gill arch. Otherwise, there was no significant site preference of worms. Only minor histopathological changes were found at the sites of attachment, and these were restricted to the epithelial cells of the primary lamellae of thegill filaments. The lack of seasonal periodicity in this tropical monogenean is compared to seasonal cycles typical of temperate species.

Efectos del parasitismo sobre el tejido branquial en peces cultivados: estudio parasitologico e histopatologico

One hundred four out of 225 diagnosticated cases were myxosporidian, monogenean, Ichthyophthirius multifiliis Fouquet, 1876 and bacterial diseases in Piaractus mesopotamicus Holmberg, 1887 (pacu), Colossoma macropomum Cuvier, 1818 (tambaqui) and tambacu, at Aquaculture Center, Universidade Estadual Paulista (UNESP), Jaboticabal, São Paulo, Brazil, between 1992 and 1995. The gills were fixed in 10% buffered formalin solution to posterior histologic routine. It was observed Henneguya sp. cysts into the capillaries of the secondary lamellae, encapsulated by the respiratory epithelium cells. It provoked adherence of the adjacent lamellae, hyperplasia, congestion, oedema and epithelium displacement. Monogeneans infestations by Anacanthorus penilabiatus Boeger, Husak & Martins, 1995 and Ancyrocephalinae sub-family caused light inflammatory reaction and hyperplasia. In severe infestations was observed hyperplasia of primary lamellae, necrosis, oedema, respiratory epithelium displacement, ruptured pillar cells and telangiectasis. Response to I. multifiliis was limited to surrounding epithelial cells in young fishes and hyperplasia, necrosis, inflammatory infiltrate and oedema in old fishes. Such lesions iniciate hyperplasic and oedematous process that with inflammation of the parasitic sites, provoked alterations over gases and ions interchange surface and consequently fish metabolism.

Diversidade de helmintos de Ageneiosus ucayalensis Castelnau 1855 (Pisces siluriformes) da foz do Rio Guamá e Baia do Guajará, Belém, Pará

Estudos em taxonomia descritiva de helmintos de peixes na Amazônia são relevantes, visto a grande diversidade de hospedeiros conhecidos. Este estudo visou analisar o parasitismo de Ageneiosus ucayalensis identificando e descrevendo novos helmintos, e referenciar novos hospedeiros para Espécies de helmintos conhecidos, utilizando como ferramentas microscopia de luz, eletrônica de varredura e biologia molecular. A. ucayalensis, peixe Siluriformes de água doce da América do Sul é uma Espécie pouco estudada, frente à sua importância na cadeia trófica de ambientes dulcícolas e de seu valor na composição da dieta alimentar de populações ribeirinhas amazônicas. Esses hospedeiros habitam a região da foz do rio Guamá e baía do Guajará e estão parasitados por helmintos dos Filos Plathyhemintes, Acanthocephala e Nematoda os quais foram aqui descritos pela primeira vez. Neste estudo foram descritas duas novas Espécies de Nematoda, Procamallanus (Spirocamallanus) belenensis e Cucullanus ageneiosus; novo hospedeiro e nova localidade de ocorrência foram descrita para Procamallanus (Spirocamallanus) rarus; além de formas larvais de nematóides das Famílias Anisakidae (Anisakis sp.), Cystidicolidae (Pseudoproleptus sp.) e Cucullanidae (Cucullanus sp.) como parasitos de A. ucayalensis. Do Filo Plathyhelmintes, a Classe Cestoda está representada por metacestódeos e adultos da Família Proteocephalidae. A Classe Monogenea está representada por helmintos da Família Dactylogiridae, Sub-Família Ancyrocephalinae e o Filo Acanthocephala por exemplares da Família Neoechinorhynchidae (Gênero Neoechinorhynchus). Assim, o estudo da helmintofauna de A. ucayalensis contribui com importantes dados para a biodiversidade de parasitos da região amazônica.