ASPECTOS ECOLÓGICOS DE MONOGENEOS PARÁSITOS BRANQUIALES (PLATYHELMINTHES) DE HOPLIAS AFF. MALABARICUS (BLOCH, 1794) (PISCES, ERYTHRINIDAE) EN UNA PLANICIE DE INUNDACIÓN NEOTROPICAL

We analyzed 54 specimens of Hoplias aff. malabaricus (Bloch, 1794) collected between March 2010 and March 2011 from the upper Paraná river Neotropical floodplain, Brazil. All hosts were parasitized by at least one species of Monogenea. The parasites species with higher prevalence were Urocleidoides cuiabai Rosim, Mendoza-Franco & Luque, 2011 (96.29 %) and U. malabaricusi Rosim, Mendoza-Franco & Luque, 2011 (92.59%). The community of gill ectoparasites examined showed an aggregated pattern. Urocleidoides cuiabai was the dominant species in the sample (C > 0.25). The parasitic abundance showed significant positive correlation with the standard length of the host for U. malabaricusi and U. eremitus Kritsky, Thatcher & Boeger, 1986. There were significant differences in the abundance values between male and female fish to the species of parasites Urocleidoides brasiliensis Rosim, Mendoza-Franco & Luque, 2011 and U. cuiabai. The gonad maturation stages of the host did not influence the levels of parasitism. Four species of parasites showed positive and significant correlation with parasitic abundance and the relative condition factor. The Ivinheima river presented higher abundance of parasitism in relation to other subsystems. The ecological study of monogeneans can provide a greater knowledge of the biology of these parasites and their hosts, the collection site, and even how the host responds to the presence of these parasites. We discuss the factors that were fundamental in the levels of parasitism in this important fish species in the floodplain of the upper Paraná river.Analizamos 54 especímenes de Hoplias aff. malabaricus colectados entre marzo de 2010 y marzo de 2011 en la planicie de inundación Neotropical del alto rio Paraná, Brasil. Todos los hospederos fueron parasitados por lo menos con una especie de Monogenea. Las especies de parásitos con las mayores prevalencias fueran Urocleidoides cuiabai (96,29 %) y U. malabaricusi (92,59%). La comunidad de ectoparásitos de branquias ha presentado patrón de distribución agregado. Urocleidoides cuiabai fue la especie dominante en la muestra (C > 0,25). La abundancia del parasitismo ha presentado correlación positiva y significativa con la longitud estándar del hospedero para las especies U. malabaricusi y U. eremitus Kritsky, Thacher & Boeger, 1986. Hubo diferencia significativa en la abundancia de parasitismo entre peces machos y hembras para los parásitos U. brasiliensis y U. cuiabai. La fase de maduración gonadal del hospedero no influyó los niveles de parasitismo. Cuatro especies de parásitos han presentado una correlación positiva y significativa con la abundancia de parasitismo y el factor de condición relativo. El rio Iviñeima ha presentado alta abundancia de parasitismo en relación a otros subsistemas. El estudio ecológico de monogeneas puede proveer un gran conocimiento de la biología de estos parásitos y sus hospederos, el sitio de colecta, y hasta como el hospedero responde a la presencia de estos parásitos. Este artículo presenta los factores que fueron fundamentales en los niveles de parasitismo en esta importante especie de pez en la planicie de inundación del alto rio Paraná

Ocorrência e aspectos ecológicos de metazoários parasitos de peixes do Lago do Parque do Ingá, Maringá, Estado do Paraná = Occurrence and ecological aspects of the metazoan fish parasites from Ingá lake, Maringá, Paraná State

Nenhum estudo de peixes e parasitos foi realizado, até o momento, no Lago do Parque do Ingá que sofre influências antrópicas desde seu represamento, em 1970. Este trabalho analisou alguns aspectos ecológicos dos parasitos metazoários dos peixes deste lago. Dos peixes analisados, (69,5%) estavam parasitados por pelo menos uma espécie de parasito. Foram encontrados 1.372 parasitos pertencentes à Nematoda (larvas) e Platyhelminthes (Monogenea e Cestoda), sendo estes os mais prevalentes e numerosos. O encontro de larvas decestóides em Tilapia rendalli e Oreochromis niloticus confirma a importância destas espécies como participantes de níveis tróficos intermediários. A maior abundância de T. rendalli e O. niloticus,no local, pode ser um fator determinante no recrutamento de parasitos. O parasito aproveita-se das espécies de hospedeiros mais abundantes para garantir o desenvolvimento de seu ciclo de vida e também por serem os mais disponíveis à predação pelas aves piscívorasali presentes, o que torna o local de grande importância para a sustentação do ciclo de vida desses parasitos. A baixa diversidade de endoparasitos coletados pode ser justificada pela presença de metais pesados – Cu e Pb – no sedimento, o que deve estar interferindo nodesenvolvimento dos invertebrados, possíveis hospedeiros intermediários.Ingá lake was dammed in 1970 and, since then, no study on fish and parasites had been done, but it has suffered anthropic influences. This study analyzed some ecological aspects of the metazoan parasites form this lake. From analyzed fish, 69.5% had at least one species of parasite. Among them, 1.372 parasites were found, prevailing Nematoda (larvae) and Platyhelminthes (Monogenea and Cestoda). The discovery of cestode larvae in Tilapia rendalli and Oreochromis nitolicus confirms the importance of these species as participants of intermediate trophic levels. The great number of Tilapia rendalli and Oreochromis nitolicus in the lake can be a determining factor for thepresence of parasites, because they take advantage of host species that are plentiful to guarantee the development of their life cycle and also because they are more susceptible to predator birds, which makes it a place of great importance for the continuation of theseparasites life cycle. The low diversity of endoparasites collected can be justified by the presence of heavy metal – Cu and Pb – on the sediment, which must be interfering in the invertebrate development, a possible intermediate host

<b>Ocorrência e aspectos ecológicos de metazoários parasitos de peixes do Lago do Parque do Ingá, Maringá, Estado do Paraná</b> - DOI: 10.4025/actascibiolsci.v29i3.507 <b>Occurrence and ecological aspects of the metazoan fish parasites from Ingá lake, Maringá, Paraná State</b> - DOI: 10.4025/actascibiolsci.v29i3.507

Nenhum estudo de peixes e parasitos foi realizado, até o momento, no Lago do Parque do Ingá que sofre influências antrópicas desde seu represamento, em 1970. Este trabalho analisou alguns aspectos ecológicos dos parasitos metazoários dos peixes deste lago. Dos peixes analisados, (69,5%) estavam parasitados por pelo menos uma espécie de parasito. Foram encontrados 1.372 parasitos pertencentes à Nematoda (larvas) e Platyhelminthes (Monogenea e Cestoda), sendo estes os mais prevalentes e numerosos. O encontro de larvas de cestóides em <em>Tilapia rendalli</em> e <em>Oreochromis niloticus</em> confirma a importância destas espécies como participantes de níveis tróficos intermediários. A maior abundância de <em>T. rendalli</em> e <em>O. niloticus</em>, no local, pode ser um fator determinante no recrutamento de parasitos. O parasito aproveita-se das espécies de hospedeiros mais abundantes para garantir o desenvolvimento de seu ciclo de vida e também por serem os mais disponíveis à predação pelas aves piscívoras ali presentes, o que torna o local de grande importância para a sustentação do ciclo de vida desses parasitos. A baixa diversidade de endoparasitos coletados pode ser justificada pela presença de metais pesados – Cu e Pb – no sedimento, o que deve estar interferindo no desenvolvimento dos invertebrados, possíveis hospedeiros intermediários.<br>Ingá lake was dammed in 1970 and, since then, no study on fish and parasites had been done, but it has suffered anthropic influences. This study analyzed some ecological aspects of the metazoan parasites form this lake. From analyzed fish, 69.5% had at least one species of parasite. Among them, 1.372 parasites were found, prevailing Nematoda (larvae) and Platyhelminthes (Monogenea and Cestoda). The discovery of cestode larvae in <em>Tilapia rendalli</em> and <em>Oreochromis nitolicus</em> confirms the importance of these species as participants of intermediate trophic levels. The great number of <em>Tilapia rendalli</em> and <em>Oreochromis nitolicus</em> in the lake can be a determining factor for the presence of parasites, because they take advantage of host species that are plentiful to guarantee the development of their life cycle and also because they are more susceptible to predator birds, which makes it a place of great importance for the continuation of these parasites life cycle. The low diversity of endoparasites collected can be justified by the presence of heavy metal – Cu and Pb – on the sediment, which must be interfering in the invertebrate development, a possible intermediate host

Ecological aspects of monogenean gill parasites (platyhelminthes) from hoplias aff. malabaricus (bloch, 1794) (pisces, erythrinidae) in a neotropical floodplain

We analyzed 54 specimens of Hoplias aff. malabaricus (Bloch, 1794) collected between March 2010 and March 2011 from the upper Paraná river Neotropical floodplain, Brazil. All hosts were parasitized by at least one species of Monogenea. The parasites species with higher prevalence were Urocleidoides cuiabai Rosim, Mendoza-Franco & Luque, 2011 (96.29 %) and U. malabaricusi Rosim, Mendoza-Franco & Luque, 2011 (92.59%). The community of gill ectoparasites examined showed an aggregated pattern. Urocleidoides cuiabai was the dominant species in the sample (C > 0.25). The parasitic abundance showed significant positive correlation with the standard length of the host for U. malabaricusi and U. eremitus Kritsky, Thatcher & Boeger, 1986. There were significant differences in the abundance values between male and female fish to the species of parasites Urocleidoides brasiliensis Rosim, Mendoza-Franco & Luque, 2011 and U. cuiabai. The gonad maturation stages of the host did not influence the levels of parasitism. Four species of parasites showed positive and significant correlation with parasitic abundance and the relative condition factor. The Ivinheima river presented higher abundance of parasitism in relation to other subsystems. The ecological study of monogeneans can provide a greater knowledge of the biology of these parasites and their hosts, the collection site, and even how the host responds to the presence of these parasites. We discuss the factors that were fundamental in the levels of parasitism in this important fish species in the floodplain of the upper Paraná river

Molecular markers in studies on fish parasites (Platyhelminthes): Review

Studies with molecular markers are currently more common for all groups of living organisms. Molecular techniques used in Platyhelminthes parasites of fishes do not merely reveal complex life cycles, but are important for species distinction and the elucidation of the phylogenetic hypothesis. Current research verified which molecular markers were mainly used phylogenetic studies on Platyhelminthes parasites of fish so that subsidies for further phylogenetic studies in Icthyoparasitology could be provided. Data base of CAPES Journals platform was employed for bibliometric analysis comprising the keywords “fish” and “phylogeny” associated with “Cestoda”, “Digenea” or “Monogenea”. Information retrieved was quantified and tabulated. Most studies were on Monogenea (43%), followed by Digenea (37%) and Cestoda (18%). Ribosomal molecular markers were the most used in the phylogenetic studies for fish parasites. Due to the advance of molecular biology techniques and of bioinformatics, with more robust phylogenetic analysis, the use of these techniques in other areas such as Ichytioparasitology is on the increase. In fact, molecular phylogenetics and morphological structures analysis have efficiently contributed towards the understanding of phylogenetic relationships among the groups.