Henneguya (Cnidaria: Myxobolidae) species infecting Oligosarcus jenynsii (Characiformes: Characidae) in a Neotropical shallow lake from Argentina: morphological and molecular characterisation.

Two previously undescribed myxozoan species, Henneguya sardellae sp. n. and H. margaritae sp. n., found infecting connective tissues of the Neotropical characid fish Oligosarcus jenynsii (Günther) from Argentina are morphologically and molecularly characterised. Mature spores of H. sardellae sp. n. are ellipsoid, with two, straight and visibly fused caudal appendages cleaved at its blunt terminal end; measuring 33.5 ± 1.2 (30.9-35.5) µm in total length, spore body 17.5 ± 0.6 (16.3-18.6) µm, 7.8 ± 0.4 (7.0-8.8) µm wide and 6.9 ± 0.2 (6.6-7.2) µm thick, with two elongated, unequally-sized polar capsules situated at anterior end, and 11-13 turns of polar tubules. Mature spores of H. margaritae sp. n. are pyriform, with two caudal appendages visible fused together and much longer than spore body, with unequal endings; measuring 35.9 ± 2.8 (29.2-40.7) µm in total length, spore body 11.5 ± 0.9 (9.2-13.0) µm long, 5.8 ± 0.4 (5.1-6.7) µm wide and 5.5 ± 0.2 (5.1-5.8) µm thick, with two polar capsules similar in size, pyriform polar capsules containing polar tubules with 4-5 coils. Both species showed a membraneous sheath surrounding the spore body and caudal appendages; in H. sardellae sp. n. this feature can deploy laterally. Phylogenetic analyses based on SSU rDNA sequences showed that H. sardellae sp. n. and H. margaritae sp. n. clustered with other myxobolids parasitising Characiformes in Brazil, Cichliformes in Mexico and Cyprinodontiformes in Mexico and the United States. The description of these two new species of Henneguya as the first described species of the genus that parasitise freshwater fish in Argentina highlights the importance of further research on the diversity and distribution of myxozoans in this region.

Allergenic response induced by Pterobothrium crassicolle (Cestoda: Trypanorhyncha) extracts in murine model / Resposta alergênica induzida por extratos de Pterobothrium crassicolle (Cestoda: Trypanorhyncha) em modelo murino

Abstract The aim of this study was to determine the allergenic activity of components present in crude extracts of Pterobothrium crassicolle plerocerci (CPE) and blastocysts (CBE) obtained from Micropogonias furnieri in a murine model. Two groups of seven animals each received 50 µg of CPE or CBE on days 1, 35 and 120. Serum samples were tested by ELISA and Immunoblotting. Specific IgG and IgE levels were detected by ELISA, showing specific humoral responses for the primary immunization for both immunoglobulins and continuously growing titers for IgE. Positive Passive Cutaneous Anaphylaxis tests in rats sensitized with anti-CBE sera and tested by CBE, showed biologically, the allergenic activity of the extracts. The CPE and CBE showed some different recognition regions but both experimental groups recognized all regions of the extracts when tested for cross reactions, showing that CPE and CBE could share antigenic recognition sites.

Resumo O objetivo deste estudo foi determinar a atividade alergênica de componentes presentes em extratos crus de plerocercos (CPE) e de blastocistos de Pterobothrium crassicolle (CBE), obtidos de Micropogonias furnieri, em modelo murino. Dois grupos de sete animais receberam cada um 50 µg de CPE ou CBE nos dias 1, 35 e 120. As amostras de soro foram testadas por ELISA e Imunoblot. Os níveis específicos de IgG e IgE foram detectados por ELISA, mostrando respostas humorais específicas para a imunização primária para ambas as imunoglobulinas e títulos crescentes de IgE. Testes positivos de Anafilaxia Cutânea Passiva em ratos sensibilizados com soros anti-CBE e testados por CBE, demonstraram biologicamente, a atividade alergênica dos extratos. O CPE e o CBE evidenciaram algumas regiões de reconhecimento diferentes, mas ambos os grupos experimentais reconheceram todas as regiões dos extratos, quando testados para reações cruzadas, mostrando que o CPE e o CBE poderiam compartilhar locais de reconhecimento antigênico.

Two new species of Curvianchoratus (Monogenoidea, Dactylogyridae) parasitizing Psectrogasteramazonica (Characiformes, Curimatidae) and a new record for Curvianchoratussingularis in the Tocantins River, Maranhão, Brazil.

Several studies have demonstrated parasitism by monogenoids in characiform fish in the Neotropics. During studies on the helminth fauna of curimatids from the Tocantins River, specimens of Psectrogasteramazonica Eigenmann & Eigenmann, 1889 were examined and species of Curvianchoratus Hanek, Molnar & Fernando, 1974 were found. Species of the genus are characterized mainly by the complex shape of haptoral anchors with a modified dorsal anchor, composed by two subunits, dorsal-median and dorsal. To date, two species of Curvianchoratus are known to parasitize curimatid fishes: the type species Curvianchoratushexacleidus Hanek, Molnar & Fernando, 1974 and Curvianchoratussingularis (Suriano, 1980). During examination of specimens of P.amazonica collected in the Tocantins River, Embiral, Imperatriz, Maranhão State, Brazil, two new species of Curvianchoratus were found and are described herein. Curvianchoratuspsectrogasterisp. nov. and Curvianchoratusdominguesisp. nov. are characterized by possessing the male copulatory organ formed by a long cirrus and a claw-shaped accessory piece, connected to the base of the male copulatory organ by a ligament. The new species differs from the two known congeneric species mainly by the morphology of the dorsal-median and dorsal subunits of the dorsal anchor. Curvianchoratuspsectrogasterisp. nov. also differs from other species of the genus by the absence of the ventral bar and Curvianchoratusdominguesisp. nov. by the size and shape of the ventral bar. An amendment to the diagnosis of Curvianchoratus is provided to accommodate the new species. The present study increases the number of Curvianchoratus species to four and extends the occurrence of the genus to the Tocantins-Araguaia Basin.

A new freshwater Ceratomyxa species (Myxozoa: Ceratomyxidae) parasitizing a sciaenid fish from the Amazon Basin, Brazil.

Myxozoans of Ceratomyxidae Doflein, 1899 are common coelozoic parasites of marine life, and are also found less frequently in freshwater fish. The present study describes Ceratomyxa ranunculiformis n. sp. as a new freshwater myxosporean species infecting the gall bladder of the Amazonian sciaenid Plagioscion squamosissimus. The new Ceratomyxa was described based on its host, myxospore morphology, ribosomal rDNA gene sequencing, parasite distribution, and phylogenetic analysis. Immature and mature plasmodia were tadpole-shaped or pyriform, and exhibited slow undulatory motility. The myxospores were elongated and crescent-shaped in the frontal view, with a sutural line between two valves, which had rounded ends. The measurements of the formalin-fixed myxospores were: average length 4.9 (4.0-6.6) µm, average thickness 37.6 (32.4-43.9) µm, average posterior angle 165° (154°-173°). Two ovoid polar capsules of equal size, average length 2.0 (1.4-3.0) µm and average width 1.9 (1.4-2.4) µm, were located adjacent to the suture and contained polar filaments with 2-3 coils. The integrated comparative analysis of the morphological characteristics and molecular analyses of the ribosomal rDNA genes supported the identification of a new species of coelozoic Ceratomyxa. Maximum likelihood analyses showed the new species clustering within a well-supported clade, together with all the other Amazonian freshwater ceratomyxids.

Morphology and molecular phylogeny of Chauhanellus Bychowsky & Nagibina, 1969 (Monogenoidea) parasitizing marine catfish (Ariidae) from the Atlantic coast of South America: a new species, supplementary taxonomic information and new insights.

In this study, a new dactylogyrid species is described from the gills of two ariid fish species of the Brazilian coast, Genidens barbus and Genidens genidens, by combining morphological characters with partial 18S rDNA sequences. The new species can be distinguished from its congeners by the following morphological characteristics: a male copulatory organ (MCO), a coiled tubular shaft of around one counterclockwise ring, base with a sclerotized cap; MCO with tapered distal region; a T-shaped accessory piece; a vagina, a cup-shaped vaginal vestibule, slightly sclerotized; and a pharynx comprising a muscular, glandular bulb. Supplementary taxonomic data for Chauhanellus velum from Sciades couma (type-host) are also presented and new 18S rDNA sequences of Chauhanellus spp. from other ariid fish from South America are provided. Phylogenetic analyses based on partial 18S rDNA gene sequences placed Chauhanellus riograndinensis n. sp. and Chauhanellus velum as two early divergent lineages within Chauhanellus from South America. Finally, a way to test the monophyly of Chauhanellus and Hamatopeduncularia is also discussed, which may be useful for future studies.

Integrative Taxonomy Reveals a Panmictic Population of Henneguya longisporoplasma n. sp. (Cnidaria: Myxozoa) in the Amazon Basin.

PURPOSE: Henneguya Thélohan, 1892 is one of the most species-rich genera of myxosporean parasites and infects fish around the world. The present study describes a new species infecting the gill filaments, fins, and kidneys of Plagioscion squamosissimus (Heckel, 1840), an economically important freshwater fish distributed in watersheds in the north of South America. METHODS: A total of 108 P. squamosissimus specimens were examined from three geographic localities in the Amazon basin: the Lago Grande do Curuai, a marginal lake of the Amazon River; the Tapajós River, in the state of Pará; and the Solimões River, in the state of Amazonas, Brazil. The analyses were based on the myxospore morphology, ribosomal DNA sequencing, phylogeny, prevalence, and geographic distribution of the host and its parasite. RESULTS: Parasite prevalences were 50% in both the Tapajós and Solimões rivers, and 35.4% in the Lago Grande do Curuai. In terms of the site of infection, the prevalence total was 23.1% in the gill filament, 29.6% in the fins, and 1.8% in the kidney. Regarding gender, the prevalence was 59.5% for males, 32.5% for females, and 21.7% for undetermined sex. The specimens found here were both morphologically and molecularly identical regardless of the infected organ and geographic locality, but distinct from all other Henneguya species, revealing that the parasite reported represents a novel species named Henneguya longisporoplasma n. sp. Despite the sampling being carried out in three different geographic localities of the Amazon basin, no population-level genetic variation was observed, even in the typically more variable ITS-1 region, revealing a panmictic population of H. longisporoplasma n. sp. in this large watershed. Maximum likelihood and Bayesian analyses showed the novel Henneguya clustered as a sister branch of the subclade formed of Henneguya that infect fish belonging to the family Cichlidae. CONCLUSIONS: A novel Henneguya species was identified parasitizing P. squamosissimus. The parasite presented wide geographic distribution in the Amazon basin and genetic analyses showed it as revealing a panmictic population.

Uso da história em quadrinhos como ferramenta de divulgação do conhecimento sobre Anisakis spp. e formas de prevenção da anisaquíase, em evento de divulgação científica / Use of comics as a tool to disseminate knowledge about Anisakis spp. and ways of preventing anisakiasis, in a scientific divulgation event / Uso del cómic como herramienta para difundir conocimientos sobre Anisakis spp. y formas de prevenir la anisakiasis, en un evento de divulgación científica

As narrativas visuais, como os quadrinhos, são ferramentas populares que podem contribuir para a edu-cação e a comunicação científica para diferentes públicos. Dentro dessa perspectiva, este trabalho discute o uso de quadrinhos na disseminação do conhecimento sobre a segurança alimentar de peixes em um evento de divulgação científica. Para a ocasião, foi criada uma história, que enfatizou o conceito sobre Anisakisspp. e as metodologias de prevenção da anisaquíase. O enredo envolveu participantes de todas as idades, sugerindo fortemente que os quadrinhos são cativantes e funcionam como uma ferramenta de aprendizado, podendo contribuir para a alfabetização científifica da população, levando à promoção da saúde em níveis individual e coletivo. Destaca-se aqui a importância da produção de novos conhecimentos, que ampliem o diálogo das áreas da saúde, da ciência e da tecnologia com a sociedade. Além disso, torna-se urgente aumentar os investimentos e promover a formação avançada e continuada de divulgadores da ciência.

Visual narratives, like comics, are popular tools that can contribute to science education and communi-cation for different audiences. Within this perspective, this work discusses the use of comics in the dis-semination of knowledge about fish food safety in a scientific dissemination event. For the occasion, a story was created, which emphasized the concept of Anisakis spp. and methodologies for the prevention of anisakiasis. The plot involved participants of all ages, strongly suggesting that comics are captivating and function as a learning tool, which can contribute to the scientific literacy of the population, leading to health promotion at an individual and collective levels. We highlight the importance of producing new knowledge that expands the dialogue between the areas of health, science and technology with society. Furthermore, it is urgent to increase investments and promote advanced and continuous training for science disseminators

Las narrativas visuales, como los cómics, son herramientas populares que pueden contribuir a la educación científica y la comunicación para diferentes públicos. Dentro de esta perspectiva, este trabajo discute el uso de las historietas en la difusión del conocimiento sobre la seguridad alimentaria de los peces en un evento de divulgación científica. Para la ocasión, se creó una historia, que enfatizó el concepto de Anisakis spp. y las metodologías para la prevención de la anisakiasis. La trama involucró a participantes de todas las edades, lo que sugiere fuertemente que los cómics son cautivadores y funcionan como una herramienta de aprendiza-je, que puede contribuir a la alfabetización científica de la población, lo que lleva a la promoción de la salud a los niveles individual y colectivo. Se destaca aquí la importancia de producir nuevos conocimientos, lo que amplía el diálogo entre las áreas de la salud, la ciencia y la tecnología con la sociedad, además, es urgente incrementar las inversiones y promover la formación avanzada y continua de los divulgadores de la ciencia

A novel Ceratomyxa species (Myxozoa: Cnidaria) infecting an Amazonian catfish.

Parasites are important organisms for the health of ecosystems. While the Amazon Basin is home to a great diversity of ichthyofauna, our knowledge of myxozoan diversity in the biome remains relatively limited. The present study describes a new myxozoan species, Ceratomyxa mandii n. sp., parasitizing the gallbladder of the Amazonian catfish Pimelodina flavipinnis (Pimelodidae) from the Solimões River, in the region of Manaus, Brazil. Light and electron microscopy,  small subunit ribosomal DNA (SSU rDNA) sequencing and phylogenetic analysis were performed. The new species exhibited worm-like plasmodia with undulatory motility. The SSU rDNA based phylogenetic analysis revealed it to be a sister taxon of C. gracillima, which also parasitizes an Amazonian pimelodid fish, possibly reflecting a host-parasite co-speciation process. This study contributes to our understanding of this little sampled group of organisms.

Embryonic development of eggs and stereological analysis of body of Neoechinorhynchus buttnerae (Golvan, 1956) (Eoacanthocephala: Neoechinorhynchidae).

The egg is one of the fundamental parts of the life cycle of Neoechinorhynchus buttnerae, and this stage involves the acanthor larva. It is also the infection phase for the intermediate host. Under normal conditions, the larva inside the egg can survive for months in the environment; however, information regarding this phase of life of the parasite is scarce. In addition, there is no quantitative information about the structural composition of the parasite's body from a histological point of view. Such information is essential in order to support decisions aimed at controlling infestations by these parasites in fish farming. This study aimed to present a detailed description of the stages of embryonic development of N. buttnerae eggs, as well as a stereological evaluation of the body of adult females of the parasite. Three phases of development characterized the eggs: cell division (with four stages), formation of the internal nuclear mass (with four stages) and formation of the acanthor larva (with five stages). The ovary comprised 26.61% of the volume of the animal and most of it contained eggs (21.28%), ovarian balls (3.88%) and empty spaces (1.45%). These results are of great importance and will support future studies that seek to interrupt the life cycle of this parasite.

Integrative taxonomy of a new species of Therodamas (Ergasilidae) infecting the Amazonian freshwater fish Leporinus fasciatus (Anostomidae).

Crustaceans of the subclass Copepoda are an important component of the invertebrate aquatic fauna. They occur in all aquatic environments and include some representatives that are free-living organisms and others that have a parasitic lifestyle. The genus Therodamas comprises marine and freshwater copepods whose females are parasites of fish in their adult phase, with only seven species described so far. During a field survey of fish parasites in the Jari River, a large tributary of the Amazon River system, in Brazil, we found a new species of the genus Therodamas infecting Leporinus fasciatus. Therodamas longicollum n. sp. is the second strictly freshwater species known. Phylogenetic analysis showed that the new species is grouped in the family Ergasilidae, and divergence estimates showed that T. longicollum n. sp. diverged from its ancestor at around 66.34 Ma, in the late Upper Cretaceous. Therodamas longicollum n. sp. differs from its congeneric in that it does not have lobes and/or expansion of the anterior neck region. Besides describing a new Therodamas species, thereby increasing the diversity of the genus to eight species, this study points out the existence of a lineage of these copepods that has adapted to the freshwater environment of the Amazon. This study also corroborates the genus Therodamas as part of the family Ergasilidae.

Mitochondrial genome of Rhabdosynochus viridisi (Monogenea: Diplectanidae), a parasite of Pacific white snook Centropomus viridis.

We report the nearly complete mitochondrial genome of Rhabdosynochus viridisi - the first for this genus - achieved by combining shotgun sequencing of genomic and cDNA libraries prepared using low-input protocols. This integration of genomic information leads us to correct the annotation of the gene features. The mitochondrial genome consists of 13,863 bp. Annotation resulted in the identification of 12 protein-encoding genes, 22 tRNA genes and two rRNA genes. Three non-coding regions, delimited by three tRNAs, were found between the genes nad5 and cox3. A phylogenetic analysis grouped R. viridisi with three other species of diplectanid monogeneans for which mitochondrial genomes are available.

The life cycle of Magnivitellinum saltaensis n. sp. (Digenea: Alloglossidiidae) in Salta Province, Argentina.

We describe the alloglossiid trematode Magnivitellinum saltaensis n. sp., a parasite of the characiform fish Psalidodon endy, and its life cycle from Salta, northwest of Argentina. This is the first life cycle described for a species belonging to the genus Magnivitellinum. Cercariae emerged naturally from Biomphalaria tenagophila snails and infected experimentally exposed larvae of Diptera and Ephemeroptera as second intermediate hosts. These larvae in turn were exposed to commercially raised fish, and adults were recovered from characiform albino fish Gymnocorymbus ternetzi. Molecular analysis of natural and experimental adults showed the same genetic sequence for the partial region of 28S rDNA, thus confirming conspecificity. Comparison of these sequences with those published for M. simplex from Mexico showed 1.45% divergence, indicating that the specimens found in Salta belong to a different species, the third described of Magnivitellinum, in agreement with morphological data, geographical location, and host species composition. The new species is distinguished by its small body, vitelline follicles extending from the mid-level of the ventral sucker, Y-shaped excretory vesicle, and presence of papillae around the mouth.

An integrative taxonomic study of Susanlimocotyle narina n. gen. n. sp. (Monogenoidea, Dactylogyridae) from the nasal cavities of a marine catfish (Siluriformes, Ariidae) from the Atlantic Amazon Coast of Brazil and new molecular data of Chauhanellus spp.

Based on a taxonomic approach, combining morphological characters with DNA sequences (i.e.,18S rDNA, ITS1, 5.8S rDNA and ITS2), Susanlimocotyle n. gen. is proposed to accommodates Susanlimocotyle narina n. sp. from the nostrils of the ariid Sciades herzbergii (Bloch) from the coast of the state of Pará, Brazil. Susanlimocotyle n. gen. is characterized by species possessing: an intestinal ceca confluent posteriorly; a male copulatory organ, comprising a variable tube, articulated with the accessory piece; a sclerotized vagina, vaginal aperture dextro-ventral; an onchium; a robust ventral bar; two dorsal bars; a ventral anchor with elongated shaft and a dorsal anchor with deep root expanding into wings. In addition, new molecular data of Chauhanellus spp. are also provided and used for the evaluation of the phylogenetic relationships among monogenoids parasitizing siluriforms. Susanlimocotyle n. gen. exhibited a higher genetic divergence level for 18S rDNA (4.6 to 7.2% [83-130 bp]) with respect to Chauhanellus spp. despite sharing S. herzbergii as a host, than Hamatopeduncularia spp., (4.1 to 5.8% [75-110 bp]) from Oriental ariids. For the 18S rDNA, 5.8S rDNA, ITS1 and ITS2 regions, C. boegeri and C. susamlimae were observed to have the smallest interspecific distances, and C. velum was revealed to be the most genetically distant species to Chauhanellus. The proposal for Susanlimocotyle n. gen. is also supported by phylogenetic analysis based on the 18S rDNA gene, which supports the close relationship between the new genus and Hamatopeduncularia and Chauhanellus from ariids from the South America and Oriental regions. Moreover, the patterns towards the shared diversification between monogenoids and their ariid hosts were addressed.

Morphological and phylogenetic characterisation of Unicauda tavaresii n. sp. (Myxosporea: Myxobolidae): a parasite of the circumorbital tissue of the eye of two characiform fishes from the Amazon region of Brazil.

Myxozoans of the family Myxobolidae are common parasites in fish. The diversity and ecology of the species of the genus Unicauda are poorly known, which hampers the understanding of the distribution and prevalence of this group of parasites. In the present study, cysts containing parasites whose morphology was consistent with the genus Unicauda were found in the circumorbital region of the ocular conjunctiva of the freshwater fish Moenkhausia grandisquamis Müller & Troschel, 1845 (Characiformes: Characidae) and Triportheus angulatus Spix & Agassiz, 1829 (Characiformes: Triportheidae). The spores have an oval body and long caudal appendage, with a mean total length of 65.2 ± 5.9 µm and width of 5.2 ± 0.7 µm, with two oval and symmetrical polar capsules of 4.9 ± 0.5 µm in length and 1.4 ± 0.2 µm in width, containing polar filaments with five or six coils. An integrated comparative analysis of the morphological characteristics of this parasite and partial sequences of the SSU rDNA gene supported the identification of a new species of histozoic parasite of the genus Unicauda found in fish from the Tocantins River basin, in the eastern Brazilian Amazon region. The new species was denominated by Unicauda tavaresii n. sp.

Current Knowledge of Small Flukes (Digenea: Heterophyidae) from South America.

Fish-borne heterophyid trematodes are known to have a zoonotic potential, since at least 30 species are able to infect humans worldwide, with a global infection of around 7 million people. In this paper, a 'state-of-the-art' review of the South American heterophyid species is provided, including classical and molecular taxonomy, parasite ecology, host-parasite interaction studies and a list of species and their hosts. There is still a lack of information on human infections in South America with undetected or unreported infections probably due to the information shortage and little attention by physicians to these small intestinal flukes. Molecular tools for specific diagnoses of South American heterophyid species are still to be defined. Additional new sequences of Pygidiopsis macrostomum, Ascocotyle pindoramensis and Ascocotyle longa from Brazil are also provided.

Review of the global distribution and hosts of the economically important fish parasitic isopod genus Ceratothoa (Isopoda: Cymothoidae), including the description of Ceratothoa springbok n. sp. from South Africa.

Fish parasites from the isopod family Cymothoidae have, in recent years, received increased global attention due to both their ecological and economic importance. This is particularly true for the buccal inhabiting genus Ceratothoa Dana, 1852, whose members have been implicated in negatively impacting the health of both farmed and wild-caught fishes. As research on this group increases, so does our understanding of their host specificity and distribution. The aims of this paper were thus to review the current distribution and host records of Ceratothoa and describe a new species, Ceratothoa springbok n. sp. from South Africa. Including the new species described here, there are currently 25 accepted Ceratothoa spp. known from eight of the 12 marine biogeographical realms of the world. The majority of Cymothoidae species are known to occur in the tropical realms, whereas our analyses show that the greatest diversity of Ceratothoa spp. can be found in temperate realms. These results indicate the possibility that Ceratothoa is more diverse in temperate regions. This review also highlights the low diversity of Ceratothoa from the oceans around both North and South America. Current records indicate that species of Ceratothoa parasitise 108 fish species in 76 genera and 41 families. Eleven Ceratothoa spp. demonstrate host specificity up to host genus or family level. Amongst the hosts, members of the Sparidae are parasitised by 13 species of Ceratothoa, making it the host family with the highest diversity of parasites from this genus. The new species, C. springbok n. sp., also parasitises a sparid and was found in the buccal cavity of the carpenter seabream, Argyrozona argyrozona. This new species, the largest of all recorded Ceratothoa (up to 65 mm) and amongst the largest of all Cymothoidae, is characterised by its truncate and ventrally folded frontal margin, pereonite 1 with medial indentations, the wide anterolateral margins of pereonite 1 with an inwardly produced point, and a well-developed carina on the basis of pereopod 7. A key to the southern African Ceratothoa is provided.

Hepatic Coccidiosis in Triportheus angulatus Spix & Agassiz, 1829 (Characiformes: Triportheidae), a Tropical Fish from the Eastern Brazilian Amazon, with the Description of a New Species of Calyptospora (Apicomplexa: Calyptosporidae).

Hepatic infection involving a parasite of the family Calyptosporidae was recorded in characiform fish from the Tocantins river in the Brazilian Amazon region. In the present study, an integrated comparative analysis of morphological characteristics, histological and structural traits, and the sequence of a partial fragment of the SSUrRNA gene provides support for the identification of a new calyptosporid species, found parasitising the hepatic tissue of the fish Triportheus angulatus, collected from the Tocantins River. This new species was named Calyptospora gonzaguensis n. sp. and had ovoid oocysts with a diameter of 19.6 ± 1.4 µm and four peripheral sporocysts, 9.2 ± 0.6 µm long and 3.9 ± 0.2 µm wide, enveloped individually in fine adhesive membrane, composed of an ellipsoid body and posterior extension, with a mean length of 2.2 ± 0.4 µm.

Coelozoic parasite of the family Ceratomyxidae (Myxozoa, Bivalvulida) described from motile vermiform plasmodia found in Hemiodus unimaculatus Bloch, 1794.

Myxozoans of the family Ceratomyxidae are common coelozoic parasites of marine, anadromous, and freshwater fish, and may also be found, less frequently, parasitizing the tissue of these hosts. The diversity and ecology of the freshwater species of the genus Ceratomyxa have been poorly investigated, leading to a knowledge gap that restricts the understanding of the distribution and prevalence of this group of parasites. In the present study, parasites were found inside vermiform plasmodia, characterised by oscillatory movements in the characiform species Hemiodus unimaculatus. The crescent-shaped and elongated spores, perpendicular to the suture line, have a mean length of 28.9 ± 2.7 µm and width of 2.6 ± 0.1 µm, with two symmetrical oval polar capsules, 1.9 ± 0.3 µm in length and 1.7 ± 0.2 µm in width, containing polar filaments with three or four coils, located near the central suture, with symmetrical lateral elongations 14.3 ± 1.1 µm in length and binucleate amoeboid sporoplasm. The integrated comparative analysis of the morphological characteristics and partial SSU rRNA sequences supported the identification of a new species of coelozoic Ceratomyxa, found in the gallbladder of H. unimaculatus, from the Tocantins basin, in the municipalities of Estreito and Imperatriz in eastern Brazilian Amazonia.The new species was denominated Ceratomyxa fonsecai n. sp.

A new species of Clinostomum Leidy, 1856 in East Asia based on genomic and morphological data.

Metacercariae of Clinostomum Leidy, 1856 are frequently encountered in freshwater fish. In 2015, a provisional species of Clinostomum in People's Republic of China (PRC) was distinguished from C. complanatum (Rudolphi, 1819) in Europe based on divergent cytochrome c oxidase I (CO1). However, in subsequent studies in East Asia, the same divergent CO1 genotype was identified as C. complanatum. These matching sequences suggest that either the provisional East Asian species was incorrectly distinguished from C. complanatum in 2015 or that C. complanatum in East Asia was misidentified in later studies. We tested these alternatives by sequencing the mitochondrial genome of C. complanatum in Italy, which was 5.7% divergent from a previously published sequence from Clinostomum in PRC, including differences in 80 of 3390 (2.4%) translated amino acids. Partial CO1 sequences of specimens from PRC and those from Italy, Romania, and Turkey also each formed reciprocally monophyletic clades. Partial CO1 from the East Asian clade varied by mean 3.6% (range 2.4-4.8%) from C. complanatum from Italy, Romania, and Turkey; mean intra-clade CO1 variation was 0.3% (range 0-1.9%). Metacercariae from Europe and East Asia display significant morphometric variation, and data from the literature suggest morphological differences in the genital complex of adults. Although sequences of nuclear rDNA did not differ between isolates from the west and East Asia, taken together, these results lead us to describe a new species of Clinostomum.

Genome-wide identification of ABC transporters in monogeneans.

ATP-Binding Cassette (ABC) transporters are proteins that actively mediate the transport of a wide variety of molecules, including drugs. Thus, in parasitology, ABC transporters have gained attention as potential targets for therapeutic drugs. Among the parasitic Platyhelminthes, ABC transporters have been identified and classified in a few species of Trematoda and Cestoda but not in Monogenea. Monogeneans are mainly ectoparasites of marine and freshwater fish, although they can also be found on other aquatic organisms. Severe epizootics caused by monogeneans have been reported around the world, mainly in confined and/or overcrowded fish. The purpose of this study was to identify the ABC transporters in four species of monogeneans (Gyrodactylus salaris, Protopolystoma xenopodis, Eudiplozoon nipponicum and Neobenedenia melleni) for which genomic resources are publicly available. For comparative purposes, ABC transporters were also identified in endoparasitic (Schistosoma mansoni and Echinococcus granulosus) and free-living (Macrostomun lignano and Schmidtea mediterranea) platyhelminths. Thirty-two putative ABC transporters were identified in the genome of G. salaris, 40 in the genome of P. xenopodis, 46 in the transcriptome of E. nipponicum and 9 in a rather limited ESTs set available for N. melleni. Of the eight ABC subfamilies (A-H) known in metazoans, subfamily H was the only one not found in any monogenean species. In contrast, ABCC was the best represented subfamily. Phylogenetic analyses showed a few cases of one-to-one orthologous relationships, which agree with results from other metazoan species. We found some monogenean ABC members related to subfamilies B, C and G involved in drug resistance in humans. This information may be useful for future functional studies on ABC transporters in monogeneans.