Luiz E. R. Tavares

Community ecology of the metazoan parasites of namorado sandperches, Pseudopercis numida Miranda-Ribeiro, 1903 and P. semifasciata Cuvier, 1829 (Perciformes: Pinguipedidae), from the coastal zone of the State of Rio de Janeiro, Brazil.

One hundred and twenty-eight specimens of namorado sandperches, 62 P. numida and 66 P. semifasciata, collected between October 2002 and June 2003 off the Cabo Frio, Rio de Janeiro, Brazil (Lat 23 degrees S and Long 42 degrees W), were examined to study their metazoan parasites. Parasite communities of these fish were composed basically of endoparasites, mainly digenean and cestodes species, with low prevalence and abundance but having high parasite species richness values (at the component community level). Among these values, that found for P. numida is the highest so far recorded for marine fishes from the Neotropical Region. Thirty-nine species of metazoan parasites were collected: 36 from P. numida and 28 from P. semifasciata. Twenty-five parasite species were common to both species of namorado sandperches. Pseudopercis numida and P. semifasciata are new host records for all parasite species collected, with the exception of Microcotyle pseudopercis. Choanodera sp., Leurodera decora, Neolebouria georgenascimentoi, and Proctoeces sp. which were recorded for the first time in the South American Atlantic Ocean. Gnathia sp. from P. numida and Scolex pleuronectis from P. semifasciata were the species having the greatest dominance frequency. Parasite abundance in P. numida and P. semifasciata were positively correlated with the host total length. Only in P. numida was parasite species richness correlated positively with the host total length. No significant differences between endoparasite infracommunities of P. numida and P. semifasciata were detected. The ectoparasites of P. numida had higher values for parasite abundance, parasite richness, Brillouin index, evenness index, and Berger-Parker index than those of the ectoparasites of P. semifasciata. Comparisons among all ecto- and endoparasites showed the ectoparasites of P. numida as the most heterogeneous group. Low similarity values were observed among the three types of parasite infracommunities of the two hosts.

Similarity between metazoan parasite communities of two sympatric brackish fish species from Brazil.

Between March 2000 and February 2003, 63 specimens of Genidens barbus and 69 specimens of Aspistor luniscutis (Siluriformes: Ariidae), sympatric species from the coastal zone of Angra dos Reis (23°01′S, 44°19′W), RJ, Brazil, were necropsied to study their metazoan parasite communities. Parasite community descriptors were calculated and possible similarities statistically tested. Twenty-two species of metazoan parasites were identified, 15 species from G. barbus and 16 associated with A. luniscutis. Nine species were common to both host species; 4 of them exhibited significant differences in terms of abundance and prevalence. Mean total abundance, species richness, diversity, evenness, and Berger–Parker dominance values were not significantly different in the 2 species of fish. Similarity within parasite infracommunities showed highest homogeneity in A. luniscutis. The parasite infracommunities of A. luniscutis and G. barbus were characterized by ectoparasite dominance and scarcity of species with high prevalence. Nevertheless, low values of similarity were observed between infracommunities, and evidence for 2 distinct infracommunities groups was found.

A new species of Sciadicleithrum (Monogenea, Dactylogyridae) parasitic on Geophagus brasiliensis (Perciformes, Cichlidae) from Guandu River, Southeastern Brazil

Sciadicleithrum guanduensis sp. nov. is described from the gills of the cichlid fish Geophagus brasiliensis (Quoy et Gaimard, 1824) from Guandu River, Seropédica, Rio de Janeiro, Brazil. The new species differs from all congeners by the accessory piece of the male copulatory organ, which comprises a small, delicate sheath with articulated appearance, and by the presence of a large unique umbelliform membrane on the ventral bar.

A New Species of Acantholochus (Copepoda: Bomolochidae) Parasitic on Centropomus undecimalis (Osteichthyes: Centropomidae) from the Coastal Zone of the State of Rio de Janeiro, Brazil

A new species of Acantholochus Cressey, 1984 (Copepoda: Bomolochidae) parasitic on the gills of common snook, Centropomus undecimalis, from the coastal zone of the State of Rio de Janeiro, Brazil, is described and illustrated. The new species differs from all other species of Acantholochus by the presence of only one inner seta on middle segment of the second and third endopods.

A morphological and molecular study of two species of Raphidascaroides Yamaguti, 1941 (Nematoda: Anisakidae), parasites of doradid catfish (Siluriformes) in South America, with a description of R. moraveci n. sp.

Nematodes of the genus Raphidascaroides Yamaguti, 1941 parasitising doradid catfishes (Siluriformes: Doradidae) in Brazil were studied based on morphological and molecular evaluation of newly collected material. A new species, Raphidascaroides moraveci n. sp., is described from the intestine of Platydoras armatulus (Valenciennes) from River Miranda, River Paraguay basin, Pantanal, Mato Grosso do Sul. The new species differs from all of the congeners in having short spicules (163–217 μm in length) representing less than 1% of the total body length and in the posterior region of cloacal opening covered by small rudimentary spines. In addition, it differs from the other congeneric species in the number and arrangement of the caudal papillae and the structure of lips and tail. Raphidascaroides moraveci n. sp. is the third species described from freshwater fishes and the second one in the Neotropical Region. New morphological data on R. brasiliensis Moravec & Thatcher, 1997 from Megalodoras uranoscopus (Eigenmann & Eigenmann) and Platydoras costatus (Linnaeus) (both new host records) from River Xingu, River Amazon basin, Pará, are provided including scanning electron micrographs of taxonomically important structures. The differentiation of the new species is supported by molecular data (partial sequences of the small and large subunits of the rRNA gene).

Diet and nematode infection in Proceratoprhys boiei (Anura: Cycloramphidae) from two Atlantic rainforest remnants in Southeastern Brazil

Proceratophrys boiei is an endemic cycloramphid anuran inhabiting the leaf litter of Atlantic rainforests in Southeastern Brazil. We analyzed the whole digestive tract of 38 individuals of Proceratophrys boiei collected in two Atlantic Rainforest areas in the state of Rio de Janeiro, Brazil, to study the diet composition and the helminth fauna associated with this species. The main food items in P. boiei’s diet were Coleoptera, Orthoptera and Blattaria. Five nematode species were found: Aplectana delirae, Cosmocerca parva, Oxyascaris oxyascaris, Physaloptera sp. (larval stage only) and an unidentified nematode. Overall prevalence was 71% and mean infection intensity was 7.3 ± 5.8 nematodes per individual.

A new species of Dichelyne (Nematoda, Cucullanidae) parasitizing sciaenid fishes from off the South American Atlantic coast

A new nematode species Dichelyne (Cucullanellus) sciaenidicola sp. nov. is described based on specimens collected from the Whitemouth croaker Micropogonias furnieri (Desmarest) and the Argentine croaker Umbrina canosai Berg, from coastal waters of Argentina and Brazil. These nematodes were firstly identified as D. (C.) elongatus (Törnquist, 1931), a commonly reported species from M. furnieri in South American Atlantic waters. However, other species of Dichelyne have so far been reported from this host in the same area, namely D. (C.) rodriguesi (Pinto, Fábio et Noronha, 1970), D. (C.) amaruincai (Freitas, Vicente et Ibañez, 1969) and D. (Dichelyne) micropogonii Pereira et Costa, 1996. A careful re-examination of these parasites, as well as of type specimens of all species reported from M. furnieri, revealed that these nematodes represented a new species. The new species is distinguished from most of its congeners by having papillae 5–7 and 9 forming a subventral line close to cloaca, this feature is shared with other 6 species [D. (C.) dichelyneformis (Szidat, 1950), D. (C.) fraseri (Baylis, 1929), D. (C.) abbreviatus (Rudolphi, 1819), D. (C.) adriaticus (Törnquist, 1931), D. (C.) minutus (Rudolphi, 1819) and D. (C.) mariajuliae Alarcos, Timi, Etchegoin et Sardella, 2006)], which are readily distinguished by their body size, spicules length, distribution patterns of other papillae and position of the excretory pore and deirids. Also, D. (C.) elongatus from Umbrina canariensis (Valenciennes) from West Africa is established as a new species Dichelyne (Cucullanellus) yvonnecampanae sp. nov.; D. (C.) amaruincai from Pacific waters is considered as a valid species, D. (D.) micropogonii is regarded as species inquirendae and D. (C.) rodriguesi is identified as Cucullanus sp.

Parapharyngodon hugoi n. sp., a new nematode (Oxyuroidea: Pharyngodonidae) of the tree frog Trachycephalus typhonius (Linnaeus) from the Brazilian Pantanal, including a key to the congeners from amphibians of the American continent

Abstract A new nematode Parapharyngodon hugoi n. sp. (Oxyuroidea: Pharyngodonidae) is described parasitising the large intestine of the tree frog Trachycephalus typhonius (Linnaeus) (Anura: Hylidae) from the wetlands of Pantanal, State of Mato Grosso do Sul, Brazil. The new species exhibits a unique structure of the posterior cloacal lip in males, which is supported by a rigid V-shaped structure. Parapharyngodon hylidae parasitic in hylid frogs, including T. typhonius, from Mexico, is the most similar congener to P. hugoi n. sp. but is distinguished from the new species by the presence of a gubernaculum (vs absence), by the lateral alae in males ending far anterior to cloacal opening (vs near to it) and because in gravid females the ovaries encircle the oesophageal corpus. Additionally, the new species differs from its congeners as well as from species of Thelandros Wedl, 1862, a very closely related genus, by the combination of features such as spicule length, number of caudal papillae, morphology of the anterior cloacal lip, which is echinate, and position of ovaries. The geographical distribution of hosts seems to play an important role in the speciation process of Parapharyngodon spp.; however, due the lack of molecular data this issue along with the validity of both Thelandros and Parapharyngodon are still questions to be solved in the future, after improvement of the genetic database. A key to the species of Parapharyngodon parasitic in amphibians from the American continent is provided.

Aspectos quantitativos e morfométricos das infrapopulações de platynosomum illiciens (trematoda: dicrocoeliidae) em paroaria dominicana (passeriformes: emberizidae) do estado da Bahia, Brasil

During the study of the metazoan parasites of Paroaria dominicana Linnaeus, 1758 (Passeriformes), four infrapopulations of Platynosomum illiciens (Brown, 1901) (Trematoda), parasitic in the liver ducts were collected, with intensity of infection 10, 11, 18 and 36 specimens respectively. Differences between the means of morphometrical values and the total number of eggs were statistically tested. The liver weigh were not significantly correlated with avian total weigh and length, and with the total parasitic abundance. Positive correlations were observed between the size of infrapopulations and the total number of eggs, and between parasite body size and the eggs. size. Negative correlations were observed between parasitic intensity and liver weigh; between the size of infrapopulations and the parasite body size; between total number and the size of eggs and between parasite body size and total number of eggs. These results suggests that host with smaller liver had greater infrapopulations. These greater infrapopulations showed smaller parasite body size and higher size and number of eggs.

Metazoan parasites of Brazilian menhaden Brevoortia aurea (Spix & Agassiz, 1829) (Osteichthyes: Clupeidae) from the coastal zone of the state of Rio de Janeiro, Brazil

Curso de Pos-graduacao em Ciencias Veterinarias, Departamento de Parasitologia Animal, Universidade FederalRural do Rio de Janeiro, C.P. 74508, CEP 23851-970, Seropedica, RJ, BrazilCorrespondence to: Jose Luis Luque, Departamento de Parasitologia Animal, Universidade Federal Rural do Rio deJaneiro, C.P. 74508, CEP 23851-970, Seropedica, RJ, Brazil, e-mail: jlluque@ufrrj.brReceived December 16, 2002 – Accepted April 17, 2003 – Distributed August 31, 2004