Community structure of helminth parasites of the “Cururu” toad, Rhinella icterica (Anura: Bufonidae) from southern Brazil

Sixty specimens of the “cururu” toad, Rhinella icterica (Spix 1824) (Bufonidae), were collected in Campo Belo do Sul, State of Santa Catarina, Brazil, between May 2009 and January 2011, and were examined for the presence of helminth parasites. Nine species of adult helminths were found: Catadiscus cohni, Rudolphitrema rudolphii, Cylindrotaenia sp., Rhabdias fuelleborni, Strongyloides sp., Cosmocerca rara, Cosmocerca brasiliensis, Aplectana elenae, and Oxyascaris sp., in addition to an unidentified adult nematode species. Females of cosmocercid nematodes, proteocephalan plerocercoid, and acanthocephalan cystacanth were found but not identified for lack absolute of taxonomic characters. The sex of the anurans had no influence on prevalence, abundance, and richness of helminth species. Length and body mass of hosts did not influence the prevalence and richness of helminths, while the abundance of R. fuelleborni was significantly correlated with both parameters.     

Ancyrocephalidae (Monogenea) of Lake Tanganyika: III: Cichlidogyrus infecting the world’s biggest cichlid and the non-endemic tribes Haplochromini, Oreochromini and Tylochromini (Teleostei, Cichlidae)

Lake Tanganyika is the deepest and oldest African Great Lake and of economic importance. While the diversity of its endemic cichlid radiations yielded scientific interest, a number of cichlid tribes have few representatives in the lake. Some of those, namely Oreochromini (ex-Tilapiini), Haplochromini and Tylochromini, reach higher species numbers in riverine systems. Conversely, the phylogenetic position of the monospecific and endemic Boulengerochromini is unclear. The oreochromines Oreochromis tanganicae and Oreochromis niloticus, the haplochromine Astatotilapia burtoni, the tylochromine Tylochromis polylepis and the boulengerochromine Boulengerochromis microlepis, the largest cichlid species worldwide, were surveyed for ancyrocephalid monogenean gill parasites. Five new species are proposed. Cichlidogyrus gillardinae sp. n. is described from A. burtoni, Cichlidogyrus mbirizei sp. n. from O. tanganicae and Cichlidogyrus nshomboi sp. n. from B. microlepis. T. polylepis harbours Cichlidogyrus mulimbwai sp. n., Cichlidogyrus muzumanii sp. n. and a third, presently undescribed species. Four species known from outside the Tanganyika Basin were retrieved on the oreochromines. The host species are scientific models or important in the sectors of fisheries or ornamental fish trade. Moreover, their phylogenetic positions render them well-suited to help elucidate the historic relationships between riverine and lacustrine African cichlids. In this framework, their Cichlidogyrus fauna is compared to congeners known from African rivers and to the few Tanganyika representatives described. While the parasites of Oreochromis, A. burtoni and T. polylepis are reminiscent of those infecting related hosts throughout Africa, B. microlepis hosts a Cichlidogyrus morphotype typical of Lake Tanganyika. This supports its placement within an endemic cichlid radiation.     

Assessment of gastrointestinal parasites in wild chimpanzees (Pan troglodytes troglodytes) in southeast Cameroon

We tested 114 faecal samples from wild simian immunodeficiency virus (SIV)-positive (n?=?43) and SIV-negative (n?=?71) chimpanzees (Pan troglodytes troglodytes) in southeast Cameroon for the presence of gastrointestinal parasites by direct smear. We observed cysts from different protozoa (Entamoeba coli and Entamoeba histolytica / Entamoeba dispar, Endolimax nana, Iodamoeba butschlii, Chilomastix mesnili, Balantidium coli and Blastocystis cells) and trophozoites from Troglodytella abrassarti and Balantidium coli. Eggs from different helminths (strongylids, Ascaris lumbricoides, Abbreviata caucasica, Trichuris sp., Capillaria sp., Enterobius anthropopeci, Bertiella sp., Hymenolepis diminuta and an undetermined fluke) were also observed. Finally, we observed eggs that could not be properly identified and classified. We did not observe any differences between the SIV?+?and SIV???samples except for the unidentified eggs. The studied chimpanzees were highly parasitised by strongylid (85.1 % of prevalence), Troglodytella (43.8 %) and Blastocystis (2.9 %), and the frequency of the other parasites ranged from 0.9 to 8.8 %. These high levels of parasite infections could represent an additional burden in a population where there is a high rate of the SIV virus in circulation.     

In vitro anthelmintic activity of root-tuber extract of Flemingia vestita, an indigenous plant in Shillong, India

The in vitro activity of root-tuber-peel extract of Flemingia vestita, an indigenous plant consumed by the natives in Northeast India, was tested against helminth parasites. Live parasites (nematode: Ascaris suum from pigs, A. lumbricoides from humans, Ascaridia galli and Heterakis gallinarum from domestic fowl; cestode: Raillietina echinobothrida from domestic fowl; trematode: Paramphistomum sp. from cattle) were collected in 0.9?% physiological buffered saline (PBS) and maintained at 37?±?1?°C. In vitro treatment of the parasites with the crude extract (50?mg/ml) in PBS revealed complete immobilization of the trematode and cestode in about 43 and 20?min, respectively. However, the cuticle-covered nematodes did not show any change in physical activity and remained viable even after a long period of exposure to the extract. Exposure of R. echinobothrida to genistein (0.5?mg/ml), an active principle isolated from the root-tuber peel, caused spontaneous loss of movement (paralysis) in 4.5?h, which was slower than the time required for praziquantel, the reference flukicide and cestodicide. The treated parasites showed structural alteration in their tegumental architecture. This study suggests the vermifugal activity of this plant extract against trematodes and cestodes.     

Parasites of commercially important fish from Lake Naivasha,Rift Valley,Kenya

In Lake Naivasha, the common carp Cyprinus carpio L. 1758 was accidentally introduced from fish farms adjacent to River Malewa in 1999 and now forms the bulk of the total fish caught. Since its introduction, no study has been made on its parasitic community nor are there any reports on ectoparasites from other fish species in this lake to the best of our knowledge. Therefore, the aim of this study was to describe the parasitic community of C. carpio and two other commercially important fish species: Oreochromis leucostictus and Tilapia zillii. Additionally, the abundant Barbus paludinosus was included in the study. A total of 286 fish (145C. carpio, 56 O. leucostictus, 18?T. zillii, and 67 B. paludinosus) were collected during the year 2011 and examined. Ten taxa of parasites were recovered from C. carpio dominated by the monogenean Dactylogyrus minutus, occurring with a prevalence (p) of 99.3 %. Thirteen taxa of parasites were identified from O. leucostictus dominated by monogeneans Cichlidogyrus spp. (p?=?91.1 %). T. zillii harbored nine taxa of parasites with the digenean Tylodelphys sp. (p?=?83.3 %) being dominant and B. paludinosus harbored 11 taxa of parasites dominated by an unidentified monogenean of the genus Dactylogyrus (p?=?83.6 %). C. carpio had the lowest helminth species diversity and richness while monogenetic trematodes, which have never been reported from fish in Lake Naivasha, were the most prevalent parasites recovered.     

Benzoquinones in stages of the life-cycle of the cestode Spirometra mansonoides

Ubiquinone-10 and rhodoquinone-10 were detected in stages of the life-cycle of a pseudophyllidean cestode, Spirometra mansonoides, by chromatographic. UV spectrophotometric, proton nuclear magnetic resonance spectrometric and electron impact mass spectrometric methods. Ubiquinone-10 was identified in 1-day-old eggs and cotacidia, and rhodoquinone-10 in coracidia, plerocercoids and adult tapeworms. Tentative identification were also made of ubiquinone-10 in procercoids and rhodoquinone-10 in 10-day-old eggs. The roles of benzoquinones in helminth aerobic and anaerobic metabolism are discussed in relation to their distribution in stages of the S. mansonoides life-cycle.     

Nematode parasites of Chelidae (Testudines) from Southern Brazil

The presence of helminths associated with freshwater turtles is rarely reported. There are no records of nematodes parasitizing Acanthochelys spixii, and for Hydromedusa tectifera, there is only the report of unidentified nematodes found in this species in Argentina. This is the first report of nematodes (Spiroxys contortus and Camallanus sp.) in A. spixii and the first record of Spiroxys contortus and Camallanus sp. in H. tectifera. This is the southernmost record of S . contortus because this nematode was previously recorded only in Mexico.     

Metazoan parasite communities of catfishes (Teleostei: Siluridae) in Benin (West Africa)

The need for more precise information on the effect of dry season on fish parasite communities in Benin lead us to undergo a focus during this season in one of the major sites of collection fry by fish farmers.Metazoan parasites were then inventoried in 166 specimens of catfishes which constituted of C larias gariepinus, Clarias ebriensis, Synodontis schall, Synodontis nigrita, and Chrysichthys nigrodigitatus (Teleostei: Siluridae). Those fishes were collected from fishermen of Agonlin-Lowé at the side of Oueme River in south Benin from November 2011 to March 2012. In total, 12 parasite species were listed comprising three Monogena (Gyrodactylus sp., Synodontella sp., and Protoancylodiscoides chrysichthes), three Cestoda (Stoeksia pujehuni, Lytocestus sp., and Cestode indeterminate), five Nematoda (Paracamallanus cyathopharynx, Procamallanus laevionchus, Cithariniella petterae, Synodontisia thelastomoides, and nematode indeterminate), and one indeterminated Copepod species. Total infestation rate varied between 83.87 and 100 % for the different fish species. This was high but independent of fish sex (χ ²?=?1.669, df?=?4, nonsignificant). The highest mean intensity and mean abundance were, respectively, 44 and 13.33. Monogenea and Nematoda have elevated frequency of dominance, and their presence in the host is significantly correlated (r?=??0.999; p?P. laevionchus and Proteoancylodiscoides, respectively, in C. gariepinus and in C. nigrodigitatus, the parasites showed clumped distribution. The component community diversity, as measured by the Shannon index (H′), revealed that S. schall had the most parasite diversity.     

Helminth parasites in native and invasive mammal populations: comparative study on the Barbary ground squirrel Atlantoxerus getulus L. (Rodentia, Sciuridae) in Morocco and the Canary Islands

A total of 51 and 21 adults of Barbary ground squirrels (Atlantoxerus getulus) were trapped during May–July 2006 from the introduced populations on Fuerteventura Island (Canary Islands) and the native populations in Morocco, respectively. One trematode, 1 cestode and 4 nematode species were recovered belonging to five families: Brachylaima sp. (Brachylaimidae), Catenotaenia chabaudi (Catenotaeniidae), Protospirura muricola (Spiruridae), Dermatoxys getula and Syphacia pallaryi (Oxyuuridae), and Trichostrongylus sp. (Trichostrongylidae). We report for the first time the presence of P. muricola, Trichostrongylus sp. and Brachylaima sp. in A. getulus. Brachylaima sp. was found in the insular population only, as a result of a diet that includes snails. The two oxyurids were found at both sites. The continental population showed higher species richness (5 vs 3 species). This is the first report of helminth parasites from A. getulus from the Canary Islands.     

Two new cryptogonimid genera (Digenea,Cryptogonimidae) from <Emphasis Type="Italic">Lutjanus bohar</Emphasis> (Perciformes,Lutjanidae): analyses of ribosomal DNA reveals wide geographic distribution and presence of cryptic species

We describe three new species of Cryptogonimidae belonging to two new genera, Caulanus gen. nov. and Latuterus gen. nov., from the large piscivorous reef fish Lutjanus bohar Forsskål, 1775, recovered from Heron and Lizard Islands off the Great Barrier Reef and Rasdhoo Atoll, Maldives. To support our morphologically based taxonomic approach, three nuclear ribosomal DNA regions (28S, ITS1 and ITS2) were sequenced and analysed to explore the geographic distribution and integrity of the putative species recovered from these widespread localities. Sequencing of the rDNA regions included multiple replicates and revealed three distinct genotypes. Two of the observed genotypes were associated with phenotypically similar specimens of Latuterus, but were each restricted to a single locality, Lizard Island, GBR or Rasdhoo Atoll, Maldives. A posteriori analysis of the associated morphotypes revealed distinct morphological differences and these consistent differences, in combination with the consistent genetic differences led to the recognition of two distinct species in the system. Caulanus is distinguished by having oral spines, caeca which open via ani at the posterior end of the body, tandem testes and uterus that extends from the posterior end of the body to the pharynx. Latuterus is distinguished by lacking oral spines, having multiple/follicular testes, a uterus that is extensive in both fore-and hindbody and vitelline follicles which are confined to the region from the pharynx to oral sucker. Caulanus thomasi sp. nov. had identical sequences for all of the rDNA regions examined from specimens recovered from all three localities, indicating that this species has a wide Indo-Pacific distribution. The species reported here are evidently restricted to Lutjanus bohar because they were never found in large numbers of other lutjanid species sampled at the same localities.     

Molecular identification larvae of Onchobothrium antarcticum (Cestoda: Tetraphyllidea) from marbled rockcod,Notothenia rossii,in Admiralty Bay (King George Island,Antarctica)

Antarctic bony fishes are infected with cestode larvae belonging to the order Tetraphyllidea (parasites as adults in chondrichthyans). Larvae of the Tetraphyllidea differ from each other in the morphology of their scoleces and represent five forms. There are larvae with bothridia subdivided into one, two and three loculi, bothridia sac-like in shape and bothridia undivided with hook-like projections. Only one species of the family Onchobothriidae, Onchobothrium antarcticum, has been described from Antarctica and larvae with trilocular bothridia were assigned to this cestode species. In this study, ten larvae obtained from Notothenia rossii and three adult specimens of Onchobothrium antarcticum isolated from Bathyraja eatonii were examined. A partial sequence of cytochrome c oxidase subunit 1 of three adult specimens and four larvae was identical. The remaining six larval sequences differed from the sequences obtained from adult cestodes. Partial sequences of lsrDNA of all analyzed larvae were identical. These results confirm the taxonomic affiliation of the larvae with trilocular bothridia parasitizing marbled rockcod in Antarctica as Onchobothrium antarcticum.     

Observations on the lipids ofOochoristica agamae (Cestoda)

An investigation of the lipids ofOochoristica agamae, an anoplocephalid cestode of theAgama lizard, was undertaken. Total lipids of the parasite accounted for 8.4% of the fresh weight; neutral lipids comprised 82.98% of the total, glycolipids, 5.01%, and phospholipids, 12.03%. The major lipid classes inO. agamae include triglycerides, cholesterol, phosphatidyl choline, and phosphatidyl ethanolamine. The 16-and 18-carbon fatty acids were predominant in the parasite. Hexadecenoic acid, usually found at low concentrations in the lipids of helminth parasites, was the most abundant of the 16-carbon fatty acids ofO. agamae (notably in the neutral lipid fraction). Although octadecatrienoic acid occurred only in trace amounts in the intestinal contents of the host, significant amounts of this fatty acid were detected in the parasite. A lack of 20-carbon fatty acids was determined in the lipids of the host's intestinal contents and the neutral lipid fraction of the parasite.O. agamae is suspected to be capable of modifying fatty acids obtained from dietary sources by chain elongation.     

Helminth component community of the paradoxal frog Pseudis platensis Gallardo, 1961 (Anura: Hylidae) from south-eastern Pantanal, Brazil

The importance of understanding the role of parasites in ecosystems and the structure of parasite communities was addressed by studying the helminth component community of the paradox frog Pseudis platensis. Thirty-two specimens of P. platensis were collected in the south-eastern Pantanal, State of Mato Grosso do Sul, Brazil, in March 2006 and April 2008, then surveyed for helminth parasites. The component community was composed of eight species: the trematodes Catadiscus propinquus, Catadiscus sp., Glypthelmins palmipedis, two metacercariae of undetermined species, the nematodes Cosmocerca podicipinus and Rhabdias sp., and an encysted larva. Catadiscus sp. dominated in the community with high prevalence (85.4%) and Berger Parker Index (0.75). Glypthelmins palmipedis was the second most prevalent and abundant species, while C. podicipinus and Rhabdias sp. were each found in only one host specimen. The high abundance of digeneans may be explained by the aquatic lifestyle of P. platensis. The helminth species found in this study were reported to infect other host species, corroborating the hypothesis that amphibian parasite communities are composed of generalist species. Pseudis platensis is a new host record for C. propinquus, C. podicipinus, and Rhabdias sp.     

New species of Gorgoderina (Digenea; Gorgoderidae) and other helminths in Euphlyctis cyanophlyctis (Anura: Dicroglossidae) from Dehradun, (Uttarakhand), India

Gorgoderina spinosa sp. nov. (Digenea, Gorgoderidae) from the bladder of the water skipper, Euphlyctis cyanophlyctis (Anura, Dicroglossidae), from Dehradun, India is described and illustrated. Gorgoderina spinosa is the 6th Indian species assigned to the genus and is separated from its congeners based upon the morphology of vitelline glands and the presence of a spinose integument. Two additional digenean species, Diplodiscus amphichrus and Ganeo tigrinus, and 3 nematode species, Cosmocerca kalesari, Gendria chauhani, and unidentified larvae were found. Diplodiscus amphichrus, Ganeo tigrinus, Cosmocerca kalesari, and Gendria chauhani have previously been reported to infect Indian individuals of Euphlyctis cyanophlyctis.     

Influence of site, season, silvering stage, and length on the parasites of the European eel Anguilla anguilla in two Mediterranean coastal lagoons of the island of Corsica, France using indicator species method

The parasites of 425 European eels, Anguilla anguilla, were studied between 2009 and 2012 in two Mediterranean coastal lagoons of the island of Corsica, France. An indicator value (IndVal) method was used for analysis, which combines measures of fidelity and specificity. Because of its resilience to detect changes in abundance, IndVal is an effective ecological bioindicator. The IndVal method demonstrated that site, season, silvering stage, and length could influence the occurrence of parasite species in European eel. A randomization test identified ten parasite species as having a significant indicator value for site (lagoons differed principally in salinity: oligohaline to polyhaline for the Biguglia lagoon and polyhaline to euhaline for the Urbino lagoon; the digeneans Bucephalus anguillae and Lecithochirium musculus, the cestodes Bothriocephalus claviceps, Proteocephalus macrocephalus, and larvae of Myzophyllobothrium sp., the nematodes Anguillicoloides crassus, and encysted larvae of Contracaecum sp., the acanthocephalan Acanthocephaloides incrassatus, the monogenean Pseudodactyogyrus anguillae, and the copepod Ergasilus gibbus); one parasite species for the spring season (the acanthocephalan A. incrassatus); six parasite species for silvering stage (yellow, pre-silver, silver; the trematodes B. anguillae and Deropristis inflata, encysted larvae of the nematode Contracaecum sp., the acanthocephalan A. incrassatus, the monogenean P. anguillae, and the copepod E. gibbus); and three parasite species for some of the five length classes (the cestode P. macrocephalus, encysted larvae of the nematode Contracaecum sp., and the monogenean P. anguillae). Data for species composition and infection levels should help to improve the management of parasitism in the populations of European eels.     

High prevalence of intestinal infections and ectoparasites in dogs, Minas Gerais State (southeast Brazil)

In the present study, 155 dogs euthanized by the Zoonotic Disease Unit of Uberlandia in Minas Gerais State (Southeast Brazil) were autopsied. Ectoparasites were collected, and the intestinal content of dogs was systematically examined for the presence of helminthic parasites. In total, we isolated 5,155 metazoan parasites of eight species (three intestinal helminth species, five ectoparasite species). The cestode Dipylidium caninum was present in 57 dogs (36.8?%), the nematodes Ancylostoma caninum in 30 (19.4?%) and Toxocara canis in 24 (15.5?%), respectively. Among the ectoparasites, 139 (89.7?%) dogs were infested with Rhipicephalus sanguineus, 115 (74.2?%) with Ctenocephalides felis, 5 (3.2?%) with Tunga penetrans and one specimen (0.7?%) with Amblyomma cajennense, while myiasis was found in one dog (0.7?%). In logistic regression analysis, young age (adjusted odds ratio 5.74; 95?% confidence interval 1.18–27.85) and male sex (3.60; 1.24–10.40) were significantly associated with toxocariasis, and crossbreed dogs (8.20; 1.52–44.31), with dipylidiasis. Male (2.23; 1.12–4.43) and crossbreed dogs (5.17; 1.17–22.83) had also a significant higher number of concomitant parasitoses. Spatial distribution of dogs by neighbourhood identified high-risk areas. Our systematic study shows that dogs in Uberlandia carry a high number of parasites which may cause zoonotic diseases in humans; therefore, further specific evidence-based intervention measures are needed.     

Spermatozoon ultrastructure of the pseudophyllidean cestode Paraechinophallus japonicus, a parasite of deep-sea fish Psenopsis anomala (Perciformes, Centrolophidae)

This paper provides the first ultrastructural data on the spermatozoon of a pseudophyllidean cestode belonging to the family Echinophallidae, Paraechinophallus japonicus, parasitizing deep-sea fish Psenopsis anomala from Japan. The mature spermatozoon contains two axonemes of the 9+“1” trepaxonematan pattern, nucleus, cortical microtubules, and electron-dense granules. Its anterior extremity exhibits a single electron-dense crested body. One of the most interesting features of the mature spermatozoon is the presence of a ring of tubular structures encircling the axoneme. This character, previously reported in species of the families Bothriocephalidae and Triaenophoridae, may be unique to pseudophyllideans of the group “Bothriocephalidea”, thus supporting the assumption that the order Pseudophyllidea is formed in fact by two unrelated clades; “Bothriocephalidea” and “Diphyllobothriidea”. The posterior extremity contains the posterior part of the nucleus and the disorganized axoneme—a character previously not described in the Eucestoda.     

Gastrointestinal parasite fauna of Emperor Penguins (Aptenodytes forsteri) at the Atka Bay,Antarctica

In general, the knowledge on parasites infecting Antarctic birds is scarce. The present study intends to extend the knowledge on gastrointestinal parasites of Emperor Penguins (Aptenodytes forsteri) at the Atka Bay, Antarctica. Fecal samples of 50 individual Emperor Penguins were collected at the Atka Bay and analyzed using the sodium-acetate-formaldehyde (SAF) method for the identification of intestinal helminth eggs and/or protozoan parasite stages. In addition, coproantigen ELISAs were performed to detect Cryptosporidium and Giardia infections. Overall, 13 out of 50 penguins proved parasitized (26 %). The following stages of gastrointestinal parasites were identified: One Capillaria sp. egg, Tetrabothrius spp. eggs, Diphyllobothrium spp. eggs, and proglottids of the cestode Parorchites zederi. The recorded Capillaria infection represents a new host record for Emperor Penguins. All coproantigen ELISAs for the detection of Cryptosporidium spp. and Giardia spp. were negative. This paper provides current data on parasites of the Emperor Penguin, a protected endemic species of the Antarctica.     

Molecular characterization of kudoid parasites (Myxozoa: Multivalvulida) from somatic muscles of Pacific bluefin (Thunnus orientalis) and yellowfin (T. albacores) tuna

The public health importance of Kudoa infection in fish remains unclear. Recently in Japan a Kudoa species, K. septempunctata, was newly implicated as a causative agent of unidentified food poisoning related to the consumption of raw olive flounder. Other marine fishery products are also suspected as causative raw foods of unidentified food poisoning. For this study, we detected kudoid parasites from sliced raw muscle tissues of a young Pacific bluefin and an adult yellowfin tuna. No cyst or pseudocyst was evident in muscles macroscopically, but pseudocysts were detected in both samples histologically. One substitution (within 1100 bp overlap) and ten substitutions (within 753 bp overlap) were found respectively between the partial sequences of 18S and 28S rDNAs from both isolates. Nucleotide sequence similarity searching of 18S and 28S rDNAs from both isolates showed the highest identity with those of K. neothunni from tuna. Based on the spore morphology, the mode of parasitism, and the nucleotide sequence similarity, these isolates from a Pacific bluefin and a yellowfin tuna were identified as K. neothunni. Phylogenetic analysis of the 28S rDNA sequence revealed that K. neothunni is classifiable into two genotypes: one from Pacific bluefin and the other from yellowfin tuna. Recently, an unidentified kudoid parasite morphologically and genetically similar K. neothunni were detected from stocked tuna samples in unidentified food poisoning cases in Japan. The possibility exists that K. neothunni, especially from the Pacific bluefin tuna, causes food poisoning, as does K. septempunctata.     

Parasites of the fish Cichla piquiti (Cichlidae) in native and invaded Brazilian basins: release not from the enemy, but from its effects

The enemy release hypothesis is frequently used to explain the success of invaders, postulating that introduced species have escaped from their native enemies, including parasites. Here, we tested this hypothesis for the tucunaré (Cichla piquiti), a predatory cichlid, and its endoparasites. First, the parasites and their influence on the condition of the hosts in the native environment, the Tocantins River (TO), were compared to an environment where the fish was introduced, the Paraná River (PR). Then, comparisons of the abundances of Diplostomidae eye flukes and Contracaecum sp. larval nematodes were made between the introduced tucunaré and two predators native to the PR, Hoplias malabaricus and Raphiodon vulpinus. Nine species of endoparasites were recorded in total, five of which occurring in both localities. Total species richness did not differ between localities, and fish condition was negatively affected by the cestodes Sciadocephalus megalodiscus only in the TO. In the PR, abundance of Contracaecum sp. did not differ between natives and invaders; however, eye flukes were more abundant in the native fish H. malabaricus, which may represent an advantage to the invader if they were competing for prey. These results did not support the idea that the escape from parasites favoured the establishment of C. piquiti in the PR. Instead, the escape from the parasites' effects seems a better explanation, and further studies examining effects on host physiology and/or fitness in the native and introduced ranges are needed.