Estão descritos aspectos morfológicos e ultraestruturais do espermatozóide de Curimata inornata V... more Estão descritos aspectos morfológicos e ultraestruturais do espermatozóide de Curimata inornata Vavi, 1989 (Pisces,Teleostei) observados com microsopia óptica e microscopia eletrônica de transmissão. O espermatozóide é constituído de cabeça, contendo um núcleo ovoide com cromatina granular densa, uma peça intermediária curta e uma cauda com a constituição axonêmica clássica de microtúbulos de 9p+2.
Extensão Rural em Foco: Apoio à Agricultura Familiar, Empreendedorismo e Inovação - Volume 2, 2020
Os parasitos do gênero Calyptospora são encontrados em órgãos e tecidos, como brânquias, fígado, ... more Os parasitos do gênero Calyptospora são encontrados em órgãos e tecidos, como brânquias, fígado, gônadas e outros. Na maioria dos casos é observado células iniciais do ciclo de vida, ou no formato de vacúolos parasitóforos, com quatro esporocistos, cada um contendo dois esporozoítos. Para o desenvolvimento deste trabalho foram utilizados 10 espécimes do peixe Crenicichla sp., coletados no Rio Uraim no município Paragominas, no estado do Pará. Após a captura, os animais foram acondicionados em sacos plásticos com aeração artificial, transportados até o Laboratório de Pesquisa Carlos Azevedo na UFRA-Belém o qual foram anestesiados e examinadas amostras da superfície corpórea e assim retirados pequenos fragmentos de locais com suspeita de parasitismos e observados e fotografados em um fotomicroscópio de luz. Dos espécimes analisados, 60% apresentaram parasitismo por protozoários do gênero Calyptospora no parênquima hepático de Crenicichla sp. Observa-se ainda a necessidade de obter conhecimentos, principalmente no sentido de potencializar estudos sobre a ictioparasitologia. Diante do pressuposto, o objetivo deste trabalho é avaliar a o parasitismo por Calyptospora sp. no peixe Crenicichla sp. oriundo do rio Uraim Paragominas, Pará.
Sphaeromyxa azevedoi n. sp. is described from the gall bladder of the goby Gobioides grahamae (Go... more Sphaeromyxa azevedoi n. sp. is described from the gall bladder of the goby Gobioides grahamae (Gobiidae) captured on the Paracauari River in Salvaterra, on Marajó Island, northern Brazil. A total of 50 G. grahamae specimens were analysed, and 15 (30%) were parasitised by the plasmodia and myxospore of Sphaeromyxa azevedoi n. sp. Large plasmodia were observed floating in the bile. These plasmodia were flat, rounded, oval or elongated, and of varying sizes. The mature myxospores, found singly or in pairs, were 27.1 ± 2.7 (20.5-30.1) μm Length and 3.8 ± 0.2 (3.5-4.4) μm Width in the valvular view. The myxospore has two polar capsules of equal size, 8.1 ± 0.6 (7.4-9.4) μm in length and 2.9 ± 0.2 (2.3-3.3) μm in width. A polar tubule was observed in each capsule, arranged perpendicularly to the principal axis, with three or four coils. The histological analysis showed that the plasmodia and myxospore are located in the lumen of the gall bladder, arranged in pairs, and the epithelium of the gall bladder presented multifocal necrosis. The SSU rDNA of Sphaeromyxa azevedoi n. sp. clusters in the 'balbianii' group of the Sphaeromyxa clade. The morphological characteristics and molecular phylogeny of Sphaeromyxa azevedoi n. sp. support its classification as a new species of the genus Sphaeromyxa, which represents an important advancement in the understanding of the diversity of the myxozoan parasite fauna of Brazilian fishes, especially considering that the new species may be detrimental to the host, a commercially important Brazilian fish species.
FIGURE 5. Phylogenetic tree generated by Bayesian Inference (BI) applied to the partial SSU rRNA ... more FIGURE 5. Phylogenetic tree generated by Bayesian Inference (BI) applied to the partial SSU rRNA gene sequences of Myxobolus arariensis sp. n. and related myxosporeans, rooted at Kudoa thyrsites and K. alliaria. The GenBank accession numbers are shown adjacent to the species names. The numbers at the nodes indicate the bootstrap support for the Bayesian Inference. M. arariensis is shown in bold type. The taxonomic order of all the species selected for the phylogenetic analysis is shown. Any values below 50% are indicated by an asterisk. GenBank Accession numbers follow the species name.
FIGURE 4. A. Histological section of the cyst and musculature of Rhamdia quelen stained with Guti... more FIGURE 4. A. Histological section of the cyst and musculature of Rhamdia quelen stained with Gutierrez, showing mature spores (MS) and imature spores (IS) of Myxobolus arariensis n. sp. (*), causing bulging (arrow) and disorganization of the muscle fibers (M). B. thick fibrous (F) wall and the adjacent musculature (M).
FIGURE 1. A. Musculature of Rhamdia quelen (Quoy and Gaimard 1824) infected by Myxobolus arariens... more FIGURE 1. A. Musculature of Rhamdia quelen (Quoy and Gaimard 1824) infected by Myxobolus arariensis n. sp. showing the whitish, ovoid pseudocyst (arrow) Scale bar: 0.6 mm. B. Fresh spores, frontal view (arrow heads). Scale bar: 10 µm.
ABSTRACT: Among the various ultrastructural studies on different species of the genus Henneguya (... more ABSTRACT: Among the various ultrastructural studies on different species of the genus Henneguya (Myxozoa), nothing has been published about the ultrastructure of the Brazilian myxozoan species. Only some light microscopy studies have been recorded. Our study describes some particularities of the life cycle stages of an unidentified species of Henneguya found in gill filaments of a fish of commercial importance, Haplosternum littorale , obtained from the low Amazon River near Belem, Brazil.
Ministerio da Educacao e Cultura, Universidade Federal Rural da Amazonia e Superintendencia de De... more Ministerio da Educacao e Cultura, Universidade Federal Rural da Amazonia e Superintendencia de Desenvolvimento da Amazonia.
The genre Nematopsis Schneider, 1892 is a parasite apicomplexo represented by several species tha... more The genre Nematopsis Schneider, 1892 is a parasite apicomplexo represented by several species that occur in some cases, such as pathogens in bivalve molluscs. Nematopsis sp. was found in the gills and mantles of bivalve Anomalocardia brasiliana (cockles nv), collected in the coastal region of Florianopolis- (SC) and Crassostrea rizophorae (Nv- mangrove oyster) of the Parana coast region near Curitiba (PR) This parasite occurs in the form of oocysts within the parasitophorous vacilolos located within phagocytic cells (phagocytes). The oocyst measures about 24-26 pm and is externally surrounded by a fine network of anastomosed microfibrils radiating from the oocyst wall. And comprising an outer wall within which lies a uninucleate cell the sporozoite. Its main cytoplasmic structures, the apical complex consisting of rhoptries, micronemes, microtabulos which are the structures that allow the inclusion of these parasites in the phylum Apicomplexa Levine, 1972.
The present study describes Hoferellus jutubensis n. sp., a myxozoan parasite found in the urinar... more The present study describes Hoferellus jutubensis n. sp., a myxozoan parasite found in the urinary bladder of the driftwood catfish Ageneiosus inermis, captured on Jutuba Island in the state of Pará, northern Brazil. A total of 30 A. inermis specimens were examined, of which 26 (86.7%) had myxospores and polysporic plasmodia of varying shapes and sizes dispersed in the lumen of the urinary bladder, either floating freely or attached to the epithelium. In the apical view, the myxospores of Hoferellus jutubensis n. sp. are rounded, 6.1 ± 0.2 (5.7-6.3) μm long and 5.5 ± 0.3 (5.2-6.0) μm wide, with two sub-spherical polar capsules, equal in size and shape, 2.5 ± 0.2 (2.3-2.7) μm long and 1.7 ± 0.2 (1.4-2.2) μm wide. The phylogenetic analysis of a partial sequence of the SSU rDNA gene, indicated that the new species is the sister taxon of Hoferellus azevedoi, with these two species forming a Brazilian lineage of Hoferellus. The comparison of the morphological and molecular data with those of the existing members of the genus confirmed the species status of Hoferellus jutubensis n. sp., which adds one further Hoferellus taxon to the known myxosporean diversity of the Amazon basin.
The present study describes a new coelozoic, eukaryotic microparasite of the genus Ellipsomyxa Kø... more The present study describes a new coelozoic, eukaryotic microparasite of the genus Ellipsomyxa Køie, 2003 (Ceratomyxidae: Myxozoa) found parasitizing the gallbladder of Satanoperca jurupari Heckel, 1840 collected in the Curiaú River Environmental Protection Area in Macapá, Amapá state, Brazil. The fish were collected using mesh cast net. The gallbladders were examined, preserved in 80% alcohol for molecular analysis (SSU rDNA gene), and fixed in Davidson for histological slide preparation. The new parasite had a prevalence of 81% in the gallbladder, asymmetric plasmodia, irregular free spores in the bladder fluid, with no cyst formation. The spores are elliptical, with characteristics of the genus Ellipsomyxa, and they had a mean length of 10.11 (8.56-10.5) μm, mean width of 7.81 (5.96-9.56) μm, and thick walls. The polar capsules are sub-spherical in shape, slightly asymmetrical, with a mean length of 3.12 (2.31-3.99) μm and mean width of 2.5 (2.22-2.95) μm, containing polar filament with five or six coils perpendicular to the longitudinal axis of the capsule. The Bayesian Inference assigned the new species to a subclade formed by a lineage of Ellipsomyxa species from the Amazon region. Ellipsomyxa tucujuensis n. sp. is the sixth species of this genus described in fish from the Amazon region, and the first for the state of Amapá.
A new myxozoan was found parasitizing the freshwater catfish, Rhamdia quelen (Quoy & Gaimard), in... more A new myxozoan was found parasitizing the freshwater catfish, Rhamdia quelen (Quoy & Gaimard), in the Marajó island, Amazon region, Brazil. The new species is described based on the results of morphological and molecular analyses. The parasite is approximately 1.5 mm in diameter and develops in the musculature of the host in the form of spherical, whitish cysts, which are visible macroscopically between the epaxial and hypaxial layers. When ruptured, these cysts produced ellipsoidal spores with a mean length of 11.4 μm (10.7–12.6) and width of 7.2 μm (6.4–7.9). Anomalous spores with a caudal elongation, vesicles in the peripheral portion of the spore and ornamentation of the valves were also observed. The results of the phylogenetic analysis of sequences of the 18S rDNA gene using Bayesian Inference indicated clear differences among the Myxobolus species that reinforced the taxonomic position of the parasite, confirming its status as a new species, denominated Myxobolus arariensis n...
Myxozoans of the family Ceratomyxidae are common coelozoic parasites of marine, anadromous, and f... more 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.
This study describes aspects of infection caused by Myxozoa of the genus Henneguya sp. in gills o... more This study describes aspects of infection caused by Myxozoa of the genus Henneguya sp. in gills of fish belonging to the species Metynnis hypsauchen. Two sampling were made in the Capim river, close to the Ribeira community, in the municipality of Ipixuna do Pará, State of Pará, Brazil, during the months of August 2018 and March 2019. The animals were captured and transported live to the Laboratório de Pesquisa Carlos Azevedo, at the Universidade Federal Rural da Amazônia (UFRA), in Belém, Pará, Brazil. The animals were examined, and after parasitism was confirmed, Differential Interference Contrast Microscopes were used, to evaluate the parasite spores. Ziehl-Neelsen stain techniques were used in histology. Necroscopic analyses of Metynnis hypsauchen specimens found parasites in 80% of the hosts (16/20), with whitish-colored cysts in the branchial filaments, containing mature spores of the genus Henneguya. The histopathological analysis indicated large areas with cystic lesions with associated ischemic necrosis. The descriptions from this study indicate that the parasite drastically compromises the host's respiratory system. Additionally, it is worth noting that parasite fauna studies of fishes in the Capim river are still a vast topic for research; this is the first record of infection by Henneguya sp. in Metynnis hypsauchen, captured in the Capim river in Ipixuna do Pará.
Article type : Original Article Silva et al.-New Calyptospora Species from the Amazon Region Titl... more Article type : Original Article Silva et al.-New Calyptospora Species from the Amazon Region Title: 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).
Morphological and Molecular Characteristics of Kudoa viseuensis n. sp. (Myxosporea: Multivalvulid... more Morphological and Molecular Characteristics of Kudoa viseuensis n. sp. (Myxosporea: Multivalvulida), Found in the Muscle of Batrachoides surinamensis (Teleostei: Batrachoididae) in the Brazilian Amazon Region lsid:zoobank.org:act:AF886D76-EC95-4EA7-8F0D-DA2D4B956A60
Ninety-seven specimens of spotfin hatchetfish, Thoracocharax stellatus, an ornamental freshwater ... more Ninety-seven specimens of spotfin hatchetfish, Thoracocharax stellatus, an ornamental freshwater species from the Amazon basin, were captured in the basin of the Guamá River in the municipality of Belém, in northern Brazil, and analysed for coccidiosis infection. Overall, 26 of the specimens were infected by apicomplexan parasites of the genus Goussia, with unsporulated forms being found in the gastric epithelium and sporulated forms in the intestinal lumen. The spheroid oocysts (mean diameter: 13.2 ± 1.7 μm) have four elliptical sporocysts. A partial sequence of the SSU rDNA of the new species was obtained, which contained 1,121 base pairs, with 43.8% guanine + cytosine (G + C), and the bases distributed as follows: A = 28.1%, C = 18.3%, G = 25.5% and T = 28.1%. The combined analysis of the morphometric and phylogenetic evidence confirmed that the specimens represented the genus Goussia and were allocated to a new species, Goussia guamaensis n. sp., which is described here.
Estão descritos aspectos morfológicos e ultraestruturais do espermatozóide de Curimata inornata V... more Estão descritos aspectos morfológicos e ultraestruturais do espermatozóide de Curimata inornata Vavi, 1989 (Pisces,Teleostei) observados com microsopia óptica e microscopia eletrônica de transmissão. O espermatozóide é constituído de cabeça, contendo um núcleo ovoide com cromatina granular densa, uma peça intermediária curta e uma cauda com a constituição axonêmica clássica de microtúbulos de 9p+2.
Extensão Rural em Foco: Apoio à Agricultura Familiar, Empreendedorismo e Inovação - Volume 2, 2020
Os parasitos do gênero Calyptospora são encontrados em órgãos e tecidos, como brânquias, fígado, ... more Os parasitos do gênero Calyptospora são encontrados em órgãos e tecidos, como brânquias, fígado, gônadas e outros. Na maioria dos casos é observado células iniciais do ciclo de vida, ou no formato de vacúolos parasitóforos, com quatro esporocistos, cada um contendo dois esporozoítos. Para o desenvolvimento deste trabalho foram utilizados 10 espécimes do peixe Crenicichla sp., coletados no Rio Uraim no município Paragominas, no estado do Pará. Após a captura, os animais foram acondicionados em sacos plásticos com aeração artificial, transportados até o Laboratório de Pesquisa Carlos Azevedo na UFRA-Belém o qual foram anestesiados e examinadas amostras da superfície corpórea e assim retirados pequenos fragmentos de locais com suspeita de parasitismos e observados e fotografados em um fotomicroscópio de luz. Dos espécimes analisados, 60% apresentaram parasitismo por protozoários do gênero Calyptospora no parênquima hepático de Crenicichla sp. Observa-se ainda a necessidade de obter conhecimentos, principalmente no sentido de potencializar estudos sobre a ictioparasitologia. Diante do pressuposto, o objetivo deste trabalho é avaliar a o parasitismo por Calyptospora sp. no peixe Crenicichla sp. oriundo do rio Uraim Paragominas, Pará.
Sphaeromyxa azevedoi n. sp. is described from the gall bladder of the goby Gobioides grahamae (Go... more Sphaeromyxa azevedoi n. sp. is described from the gall bladder of the goby Gobioides grahamae (Gobiidae) captured on the Paracauari River in Salvaterra, on Marajó Island, northern Brazil. A total of 50 G. grahamae specimens were analysed, and 15 (30%) were parasitised by the plasmodia and myxospore of Sphaeromyxa azevedoi n. sp. Large plasmodia were observed floating in the bile. These plasmodia were flat, rounded, oval or elongated, and of varying sizes. The mature myxospores, found singly or in pairs, were 27.1 ± 2.7 (20.5-30.1) μm Length and 3.8 ± 0.2 (3.5-4.4) μm Width in the valvular view. The myxospore has two polar capsules of equal size, 8.1 ± 0.6 (7.4-9.4) μm in length and 2.9 ± 0.2 (2.3-3.3) μm in width. A polar tubule was observed in each capsule, arranged perpendicularly to the principal axis, with three or four coils. The histological analysis showed that the plasmodia and myxospore are located in the lumen of the gall bladder, arranged in pairs, and the epithelium of the gall bladder presented multifocal necrosis. The SSU rDNA of Sphaeromyxa azevedoi n. sp. clusters in the 'balbianii' group of the Sphaeromyxa clade. The morphological characteristics and molecular phylogeny of Sphaeromyxa azevedoi n. sp. support its classification as a new species of the genus Sphaeromyxa, which represents an important advancement in the understanding of the diversity of the myxozoan parasite fauna of Brazilian fishes, especially considering that the new species may be detrimental to the host, a commercially important Brazilian fish species.
FIGURE 5. Phylogenetic tree generated by Bayesian Inference (BI) applied to the partial SSU rRNA ... more FIGURE 5. Phylogenetic tree generated by Bayesian Inference (BI) applied to the partial SSU rRNA gene sequences of Myxobolus arariensis sp. n. and related myxosporeans, rooted at Kudoa thyrsites and K. alliaria. The GenBank accession numbers are shown adjacent to the species names. The numbers at the nodes indicate the bootstrap support for the Bayesian Inference. M. arariensis is shown in bold type. The taxonomic order of all the species selected for the phylogenetic analysis is shown. Any values below 50% are indicated by an asterisk. GenBank Accession numbers follow the species name.
FIGURE 4. A. Histological section of the cyst and musculature of Rhamdia quelen stained with Guti... more FIGURE 4. A. Histological section of the cyst and musculature of Rhamdia quelen stained with Gutierrez, showing mature spores (MS) and imature spores (IS) of Myxobolus arariensis n. sp. (*), causing bulging (arrow) and disorganization of the muscle fibers (M). B. thick fibrous (F) wall and the adjacent musculature (M).
FIGURE 1. A. Musculature of Rhamdia quelen (Quoy and Gaimard 1824) infected by Myxobolus arariens... more FIGURE 1. A. Musculature of Rhamdia quelen (Quoy and Gaimard 1824) infected by Myxobolus arariensis n. sp. showing the whitish, ovoid pseudocyst (arrow) Scale bar: 0.6 mm. B. Fresh spores, frontal view (arrow heads). Scale bar: 10 µm.
ABSTRACT: Among the various ultrastructural studies on different species of the genus Henneguya (... more ABSTRACT: Among the various ultrastructural studies on different species of the genus Henneguya (Myxozoa), nothing has been published about the ultrastructure of the Brazilian myxozoan species. Only some light microscopy studies have been recorded. Our study describes some particularities of the life cycle stages of an unidentified species of Henneguya found in gill filaments of a fish of commercial importance, Haplosternum littorale , obtained from the low Amazon River near Belem, Brazil.
Ministerio da Educacao e Cultura, Universidade Federal Rural da Amazonia e Superintendencia de De... more Ministerio da Educacao e Cultura, Universidade Federal Rural da Amazonia e Superintendencia de Desenvolvimento da Amazonia.
The genre Nematopsis Schneider, 1892 is a parasite apicomplexo represented by several species tha... more The genre Nematopsis Schneider, 1892 is a parasite apicomplexo represented by several species that occur in some cases, such as pathogens in bivalve molluscs. Nematopsis sp. was found in the gills and mantles of bivalve Anomalocardia brasiliana (cockles nv), collected in the coastal region of Florianopolis- (SC) and Crassostrea rizophorae (Nv- mangrove oyster) of the Parana coast region near Curitiba (PR) This parasite occurs in the form of oocysts within the parasitophorous vacilolos located within phagocytic cells (phagocytes). The oocyst measures about 24-26 pm and is externally surrounded by a fine network of anastomosed microfibrils radiating from the oocyst wall. And comprising an outer wall within which lies a uninucleate cell the sporozoite. Its main cytoplasmic structures, the apical complex consisting of rhoptries, micronemes, microtabulos which are the structures that allow the inclusion of these parasites in the phylum Apicomplexa Levine, 1972.
The present study describes Hoferellus jutubensis n. sp., a myxozoan parasite found in the urinar... more The present study describes Hoferellus jutubensis n. sp., a myxozoan parasite found in the urinary bladder of the driftwood catfish Ageneiosus inermis, captured on Jutuba Island in the state of Pará, northern Brazil. A total of 30 A. inermis specimens were examined, of which 26 (86.7%) had myxospores and polysporic plasmodia of varying shapes and sizes dispersed in the lumen of the urinary bladder, either floating freely or attached to the epithelium. In the apical view, the myxospores of Hoferellus jutubensis n. sp. are rounded, 6.1 ± 0.2 (5.7-6.3) μm long and 5.5 ± 0.3 (5.2-6.0) μm wide, with two sub-spherical polar capsules, equal in size and shape, 2.5 ± 0.2 (2.3-2.7) μm long and 1.7 ± 0.2 (1.4-2.2) μm wide. The phylogenetic analysis of a partial sequence of the SSU rDNA gene, indicated that the new species is the sister taxon of Hoferellus azevedoi, with these two species forming a Brazilian lineage of Hoferellus. The comparison of the morphological and molecular data with those of the existing members of the genus confirmed the species status of Hoferellus jutubensis n. sp., which adds one further Hoferellus taxon to the known myxosporean diversity of the Amazon basin.
The present study describes a new coelozoic, eukaryotic microparasite of the genus Ellipsomyxa Kø... more The present study describes a new coelozoic, eukaryotic microparasite of the genus Ellipsomyxa Køie, 2003 (Ceratomyxidae: Myxozoa) found parasitizing the gallbladder of Satanoperca jurupari Heckel, 1840 collected in the Curiaú River Environmental Protection Area in Macapá, Amapá state, Brazil. The fish were collected using mesh cast net. The gallbladders were examined, preserved in 80% alcohol for molecular analysis (SSU rDNA gene), and fixed in Davidson for histological slide preparation. The new parasite had a prevalence of 81% in the gallbladder, asymmetric plasmodia, irregular free spores in the bladder fluid, with no cyst formation. The spores are elliptical, with characteristics of the genus Ellipsomyxa, and they had a mean length of 10.11 (8.56-10.5) μm, mean width of 7.81 (5.96-9.56) μm, and thick walls. The polar capsules are sub-spherical in shape, slightly asymmetrical, with a mean length of 3.12 (2.31-3.99) μm and mean width of 2.5 (2.22-2.95) μm, containing polar filament with five or six coils perpendicular to the longitudinal axis of the capsule. The Bayesian Inference assigned the new species to a subclade formed by a lineage of Ellipsomyxa species from the Amazon region. Ellipsomyxa tucujuensis n. sp. is the sixth species of this genus described in fish from the Amazon region, and the first for the state of Amapá.
A new myxozoan was found parasitizing the freshwater catfish, Rhamdia quelen (Quoy & Gaimard), in... more A new myxozoan was found parasitizing the freshwater catfish, Rhamdia quelen (Quoy & Gaimard), in the Marajó island, Amazon region, Brazil. The new species is described based on the results of morphological and molecular analyses. The parasite is approximately 1.5 mm in diameter and develops in the musculature of the host in the form of spherical, whitish cysts, which are visible macroscopically between the epaxial and hypaxial layers. When ruptured, these cysts produced ellipsoidal spores with a mean length of 11.4 μm (10.7–12.6) and width of 7.2 μm (6.4–7.9). Anomalous spores with a caudal elongation, vesicles in the peripheral portion of the spore and ornamentation of the valves were also observed. The results of the phylogenetic analysis of sequences of the 18S rDNA gene using Bayesian Inference indicated clear differences among the Myxobolus species that reinforced the taxonomic position of the parasite, confirming its status as a new species, denominated Myxobolus arariensis n...
Myxozoans of the family Ceratomyxidae are common coelozoic parasites of marine, anadromous, and f... more 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.
This study describes aspects of infection caused by Myxozoa of the genus Henneguya sp. in gills o... more This study describes aspects of infection caused by Myxozoa of the genus Henneguya sp. in gills of fish belonging to the species Metynnis hypsauchen. Two sampling were made in the Capim river, close to the Ribeira community, in the municipality of Ipixuna do Pará, State of Pará, Brazil, during the months of August 2018 and March 2019. The animals were captured and transported live to the Laboratório de Pesquisa Carlos Azevedo, at the Universidade Federal Rural da Amazônia (UFRA), in Belém, Pará, Brazil. The animals were examined, and after parasitism was confirmed, Differential Interference Contrast Microscopes were used, to evaluate the parasite spores. Ziehl-Neelsen stain techniques were used in histology. Necroscopic analyses of Metynnis hypsauchen specimens found parasites in 80% of the hosts (16/20), with whitish-colored cysts in the branchial filaments, containing mature spores of the genus Henneguya. The histopathological analysis indicated large areas with cystic lesions with associated ischemic necrosis. The descriptions from this study indicate that the parasite drastically compromises the host's respiratory system. Additionally, it is worth noting that parasite fauna studies of fishes in the Capim river are still a vast topic for research; this is the first record of infection by Henneguya sp. in Metynnis hypsauchen, captured in the Capim river in Ipixuna do Pará.
Article type : Original Article Silva et al.-New Calyptospora Species from the Amazon Region Titl... more Article type : Original Article Silva et al.-New Calyptospora Species from the Amazon Region Title: 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).
Morphological and Molecular Characteristics of Kudoa viseuensis n. sp. (Myxosporea: Multivalvulid... more Morphological and Molecular Characteristics of Kudoa viseuensis n. sp. (Myxosporea: Multivalvulida), Found in the Muscle of Batrachoides surinamensis (Teleostei: Batrachoididae) in the Brazilian Amazon Region lsid:zoobank.org:act:AF886D76-EC95-4EA7-8F0D-DA2D4B956A60
Ninety-seven specimens of spotfin hatchetfish, Thoracocharax stellatus, an ornamental freshwater ... more Ninety-seven specimens of spotfin hatchetfish, Thoracocharax stellatus, an ornamental freshwater species from the Amazon basin, were captured in the basin of the Guamá River in the municipality of Belém, in northern Brazil, and analysed for coccidiosis infection. Overall, 26 of the specimens were infected by apicomplexan parasites of the genus Goussia, with unsporulated forms being found in the gastric epithelium and sporulated forms in the intestinal lumen. The spheroid oocysts (mean diameter: 13.2 ± 1.7 μm) have four elliptical sporocysts. A partial sequence of the SSU rDNA of the new species was obtained, which contained 1,121 base pairs, with 43.8% guanine + cytosine (G + C), and the bases distributed as follows: A = 28.1%, C = 18.3%, G = 25.5% and T = 28.1%. The combined analysis of the morphometric and phylogenetic evidence confirmed that the specimens represented the genus Goussia and were allocated to a new species, Goussia guamaensis n. sp., which is described here.
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