Heavy Metal Accumulation in the Intestinal Tapeworm Proteocephalus macrophallus Infecting the Butterfly Peacock Bass (Cichla ocellaris), from Southeastern Brazil.

Here we evaluate the potential of heavy metal accumulation of Proteocephalus macrophallus parasitizing the Butterfly Peacock Bass (Cichla ocellaris). A total of 19 fish specimens were collected. From the hosts, samples of intestine, liver, muscle, and parasites were taken. Heavy metal concentrations (Al, As, Ba, Cd, Cr, Fe, Hg, Mg, Mn, Ni, Pb, Ti, and Zn) were obtained using Atomic Absorption Spectrometry. All analyzed elements was found in higher concentrations in the parasites comparing to its host tissues. The bioconcentration factors were higher in the intestine, varying between 5.91 (Ti) to 8.00 (Ba), followed by the muscle, 1.88 (Mg) to 6.39 (Zn), and liver, 1.67 (Al) to 2.02 (Ba). These results show that at the infection site heavy metal concentrations are reduced, since the elements are absorbed directly from the intestinal wall by the parasites. In general, P. macrophallus presents a reasonable capacity of metal accumulation comparing to its hosts.

A new species of Wallinia Pearse, 1920 (Digenea: Allocreadiidae) collected from Astyanax fasciatus (Cuvier, 1819) and A. lacustris Lucena and Soares, 2016 (Characiformes: Characidae) in Brazil based on morphology and DNA sequences.

Wallinia brasiliensis n. sp. is described from the intestine of two species of tetras-Astyanax fasciatus (Cuvier, 1819) and Astyanax lacustris Lucena and Soares, 2016-collected from the Batalha River in São Paulo State, Brazil. The new species can be clearly distinguished from the other three congeneric species by its vitelline follicles extending from the genital pore to the end of the caeca, eggs lacking operculum, a larger egg size with a consequently lower number relative to the other three species, and the ovary located opposite the anterior testis. The validity of the new species was confirmed through a phylogenetic analysis of the 28S rRNA gene which showed that the new species is the sister taxon to Wallinia mexicana Pérez-Ponce de León, Razo-Mendivil, Mendoza-Garfía, Rubio-Godoy and Choudhury, 2015, a species infecting Astyanax mexicanus (De Filippi, 1853) in Mexico.

Four new species of Ligophorus (Monogenea: Dactylogyridae) parasitic on Mugil liza (Actinopterygii: Mugilidae) from Guandu River, southeastern Brazil.

Four species of Ligophorus (Monogenea: Dactylogyridae), i.e., L. tainhae n. sp., L. brasiliensis n. sp., L. guanduensis n. sp., and L. lizae n. sp., are described. The specimens were collected from the gills of Mugil liza (Mugilidae) from the Guandu River (22 degrees 48'32"S, 43 degrees 37'35"W), State of Rio de Janeiro, Brazil, between January 2008 and March 2008. The male copulatory organ of L. tainhae n. sp. differs from the all known species of this genus in having the largest accessory piece, the length of accessory piece exceeding the length of the copulatory organ tube, and the distal tip of the lower lobe crossing the upper lobe. Ligophorus brasiliensis n. sp. and L. guanduensis n. sp. have a similar shape of the accessory piece, but in L. guanduensis n. sp. the lower lobe is larger than the upper lobe (as opposed to L. brasiliensis n. sp.), the ratio between length of upper lobe and the length of the proximal part of the accessory piece before the bifurcation is shorter and the distal tip of the lower lobe extends to the level of the upper lobe (in L. brasiliensis n. sp. the distal tip of lower lobe crossing the upper lobe). In L. lizae n. sp., the terminal bifurcations of the accessory piece are equal in length and unequal in the other 3 new species. Species of Ligophorus are recorded for the first time from Brazil.

[Quantitative aspects of metazoan parasites communities of American harvestfish, Peprilus paru (Linnaeus,1758) (Perciformes: Stromateidae), from the coastal zone of the State of Rio de Janeiro, Brazil]. / Aspectos quantitativos da comunidade de metazoários parasitos do gordinho Peprilus paru (Linnaeus, 1758) (Perciformes: Stromateidae), do litoral do Estado do Rio de Janeiro, Brasil.

Eighty and one specimens of Peprilus paru (Linnaeus,1758) (Perciformes: Stromateidae), collected from the coastal zone of the State of Rio de Janeiro, Brazil (21-23 degrees S, 41-45 degrees W) were necropsied between January 2003 to September 2003 to study their infracommunities of metazoan parasites. All fish were parasitized by two or more metazoan. Were collected eight species of metazoans parasites: four digeneans (Aponurus laguncula, Opechona sp. Lecithocladium sp. e Acanthocolphoides sp.), two nematodes (Hystherothylacium sp. e Raphidascaris sp.), one monogenean (Microcotyle sp.) and one copepod (Caligus sp.). No parasite species showed significant correlation between the body total length of the host and their abundance. The evaluation of the effect of host on parasite abundance and prevalence not showed significant results. The parasite species presented an aggregated distribution pattern. The metazoan parasite community of P. paru is characterized by the high species diversity and high values os prevalence. One pair adult endoparasites presented association.

[Community ecology of metazoan parasites of apaiarí Astronotus ocellatus (Cope, 1872) (Perciformes: Cichlidae) from Guandu river, State of Rio de Janeiro, Brazil]. / Ecologia da communidade de metazoário parasitos do apaiarí Astronotus ocellatus (Cope, 1872) (Perciformes:Cichlidae) do Rio Guandu, Estado do Rio de Janeiro, Brasil.

Thirty five specimens of apaiarí Astronotus ocellatus (Cope, 1872) from Guandu river, (22 degrees 48'32''S, 43 degrees 37'35''W), state of Rio de Janeiro, Brazil were studied for their metazoan parasites from December 2004 to November 2005. A total of six species of metazoan parasites were collected and identified. Gussevia sp. (Monogenea) was the more prevalent species (71.4%) with highest mean intensity value (17.6), followed for the acanthochepalan Polymorphus sp. (cystacanth) which showed prevalence of 17.1%. No parasite species showed significant correlation between the body total length of the host and their prevalence and abundance. The sex of the hosts influenced the abundance of the acanthochepalan Polymorphus sp., being the females more parasitized. The parasite species richness showed a mean value of 1.11+/-0.86 (0-3). The parasite species presented an aggregated distribution pattern.

[Community ecology of metazoan parasites of Cyphocharax gilbert (Quoy e Gaimard, 1824) (Characiformes: Curimatidae) from Guandu river, State of Rio de Janeiro, Brazil]. / Ecologia da comunidade de metazoários parasitos do sairú cyphocharax gilbert (Quoy e Gaimard, 1824) (Characiformes: Curimatidae) do Rio Guandu, Estado do Rio de Janiero, Brasil.

Sixty specimens of Sairú Cyphocharax gilbert (Quoy and Gaimard, 1824) from River Guandu, (22 degrees 48'32'S, 43 degrees 37'35''"W), State of Rio de Janeiro, Brazil were studied for their metazoan parasites during May 2004 and February 2005. A total of seven species of metazoan parasites were collected and identified: Sphinctero- diplostomum musculosum (metacercariae), Diplostomum (A.) compactum (metacercariae), Zonocotyloides haroltravassosi, Cosmoxynemoides aguirrei, Travnema araujoi, Raphidascaris sp. (larval) and Placobdella sp. Sphincterodiplostomum musculosum (Diplostomidae) founded in the eyes, was the more prevalent (40%) with highest mean intensity value (11.2). The nematodes C. aguirrei and T. araujoi (Pharyngodonidae) showed prevalence higher than 10%. Only S. musculosum showed significant correlation between the host total length and the parasite abundance. The parasite species richness showed a mean value of 0.9 + 0.88 (0-3). The evaluation of the effect of host sex on parasite prevalence and abundance not showed significant results. The metazoan parasite community of C. gilbert is characterized by the low species diversity and for dominance of species with low values of prevalence.