Morphology and phylogeny of Coccomyxa bragantinensis n. sp. (Cnidaria: Myxozoa) found parasitising the Coco Sea catfish, Bagre bagre (Siluriformes: Ariidae), captured off the coast of Northern Brazil.

The present study describes Coccomyxa bragantinensis n. sp., which was found parasitising the gallbladder of the Coco Sea catfish, Bagre bagre, captured off Ajuruteua beach, in the region of Bragança in Pará state, northern Brazil. Most (77.5%) of the 40 fish specimens examined (31/40) had myxospores floating in the bile liquid. These spores are partially ellipsoid, with a tapering anterior extremity and a rounded, elongated posterior extremity with a single piriform polar capsule containing a helicoidal polar filament, with 5-6 coils. A partial sequence of 957 bp of the SSU rDNA gene was obtained from the specimens and deposited in GenBank (xxx). The new species described here - Coccomyxa bragantinensis n. sp. - is phylogenetically similar to Coccomyxa morovi, although it differs from all the other Coccomyxa species and is the first species of this genus to be described from Brazil on the basis of molecular evidence.

Sphaeromyxa azevedoi n. sp. (Myxozoa: Sphaeromyxidae) infecting the gall bladder of Gobioides grahamae (Perciformes: Gobiidae) in the Amazon region.

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.

Utrastructure and molecular phylogeny of the myxozoan Kudoa ocellatus n. sp. (Myxozoa: Kudoidae), a parasite of the Oscar, Astronotus ocellatus (Agassiz, 1831; Teleostei: Cichlidae), a fish from northern Brazil.

Kudoa ocellatus n. sp. was found in the musculature of Astronotus ocelattus (Agassiz, 1831) from the Arari River on Marajó Island in Pará, Brazil. The new species forms pseudocysts in the epaxial and hypaxial musculature composed of various spores that are pseudoquadrate in the apical view. In the lateral view, the spores were triangular or pyramidal. In the lateral view, the spores were 46 ± 0.11 µm (4.5-4.8) in length and 6.6 ± 0.3 µm (6.2-7.2) in width, with four pyriform polar capsules of equal size that measured 2.0 ± 0.16 µm (1.8-2.2) in length and 1.5 ± 0.18 µm (1.3-1.8) in width. Based on the partial (1418 bps) sequence of the SSU rDNA gene, Kudoa ocellatus n. sp. was distinct from all the other Kudoa species deposited in GenBank. The phylogenetic Bayesian Inference and P distance placed the new species together with the other Kudoa species that parasitize freshwater Amazonian fish. The morphological evidence, together with the SSU rDNA gene sequence, supported the description of Kudoa ocellatus n. sp., a distinct new species of the genus, which parasitizes a freshwater Amazonian cichlid.

Morphology and molecular phylogeny of Hoferellus jutubensis n. sp. (Cnidaria: Myxozoa) found parasitising Ageneiosus inermis (Siluriformes: Auchenipteridae), in the Brazilian Amazon region.

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.

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.

Morphology and Phylogeny of Calyptospora paranaidji n. sp. (Eimeriorina: Calyptosporidae), an Apicomplexan Parasite of the Hepatic Tissue of Cichla piquiti Kullander & Ferreira, 2006, From a Reservoir in the Brazilian Amazon Region.

The coccidians of the family Calyptosporidae are parasites of the tissue and organs of fish and aquatic invertebrates, in particular in the tropical region. In contrast with other apicomplexans of the suborder Eimeriorina, the diversity and ecology of the species of the genus Calyptospora have been poorly investigated, resulting in a lacuna that restricts the understanding of the distribution and prevalence of this group of eukaryote microparasites in the Amazon region. In the present study, the integrated comparative analysis of morphological characteristics, histological and structural traits, and the sequences of a fragment of the 18S rRNA gene, provides support for the identification of a new species of Calyptospora, found parasitizing the hepatic tissue of the piscivorous blue peacock bass, Cichla piquiti, captured in the reservoir of the Estreito hydroelectric dam on the middle Tocantins River in northern Brazil. This new species was named Calyptospora paranaidji n. sp.

A new species of Myxosporea, Henneguya quelen, from silver catfish Rhamdia quelen (Siluriforme: Pimelodidae) in the Amazonian region.

Henneguya quelen n. sp. (Myxosporea) is described from the kidney of the silver catfish, Rhamdia quelen (Quoy & Gaimard, 1824), from Marajó Island. In all, 40% of the 57 silver catfish collected from the Paracauari River in the municipality of Salvaterra presented cysts in the kidney. The cysts were whitish, spherical, and 0.45 mm in diameter. The histological analyses revealed tubular renal compression and cellular degeneration in the area adjacent to the xenomas. The spores are ellipsoid, with well-marked valves, caudal projection, and two elongated polar capsules of equal size. The mature spores measure approximately 15.6 µm in length, with the caudal appendage split posteriorly; 24.3 µm in length, for a total spore length of 40.0 µm; and a width of 4.1 µm. The polar capsules are pyriform, 5.5 µm long and 1.7 µm wide. A phylogenetic analysis based on Bayesian inference confirmed that the specimens represented a new species, which was denominated Henneguya quelen n. sp.

Morfologia e morfometria da traqueia da preguiça (bradypus variegatus): conhecimentos para procedimentos de emergência / Morphological and morphometric trachea sloth (bradypus variegatus): knowledge for emergency procedures

Por ser uma espécie pouco estudada, principalmente do ponto de vista morfológico, objetivou-se conhecer a anatomia da traqueia da preguiça (Bradypus variegatus) a fim de fornecer informações para facilitar a eleição de tubo endotraqueal adequado, máscara laríngea ou cânula de traqueostomia para anestesia e procedimentos de emergência, uma vez que a mesma revelou-se possuidora de uma morfologia especial. Foram investigados 11animais jovens de idades diferentes, sendo quatro machos e sete fêmeas, provenientes do Museu Emilio Goeldi e doados a UFRA. Os exemplares foram perfundidos via intramuscular com solução aquosa de formol a 10% para fins de conservação e posteriormente foram dissecados em nível cervico-torácico, por meio de mesoscopia, expondo-se desde a laringe até os brônquios principais direito e esquerdo ao nível do hilo pulmonar. As traqueias foram divididas em cinco regiões (região cervical, região da primeira flexura, região da segunda flexura, região da terceira flexura e região da carina) as quais foram mensuradas altura e largura, assim como o comprimento traqueal total e parte do material foi submetido à técnicas de rotina histológica. Macroscopicamente, destacou-se a presença de sinuosidades acentuadas em porção médio caudal, contemplando a carina. O comprimento médio traqueal foi de 14,6cm. Microscopicamente, a traqueia era constituída por placas separadas de cartilagem hialina constituindo cada anel, sendo revestido por epitélio estratificado ciliado. Apesar da traqueia da preguiça comum apresentar revestimento padrão encontrado na traqueia de outros animais, na literatura não há registros de outras espécies que tenham morfologia macroscópica nas condições descritas, o que nos leva a sugerir, quando necessário acesso para ventilação de emergência, a prática da IOT e não a de traqueostomia.

As the sloth (Bradypus variegatus) is a little studied species, especially from a morphological point of view, this research aimed to define the anatomy of its trachea. The information would facilitate the selection of a proper endotracheal tube, laryngeal mask or tracheostomy tube for anesthesia and emergency procedures, since it appeared to have a special morphology. Eleven young animals of different ages were investigated, four males and seven females, obtained from the Emilio Goeldi Museum and donated to UFRA. The specimens were infused intramuscularly with 10% aqueous formaldehyde for preservation and were later dissected at the cervico-thoracic level, by mesoscopia, exposing the area from the larynx to the right and left primary bronchi at the hilum. The tracheae were divided into five regions (cervical, first flexure, second flexure, third flexure, and carina) for which length and width were measured, as well as the total tracheal length. Sharp windings were seen in the middle caudal portion, including the carina. The average tracheal length was 14.6 cm. Microscopically, the trachea was made up of separate plates of hyaline cartilage forming each ring, lined with ciliated epithelium. Despite the trachea of the common sloth displaying the same lining pattern found in other animals, there are no reports in the literature of other species having a macroscopic morphology as described here, which leads us to suggest, where appropriate access to emergency ventilation, the practice of IOT and not tracheostomy.

Morphological aspects of Clinostomidae metacercariae (Trematoda: Digenea) in Hoplerytrinus unitaeniatus and Hoplias malabaricus (Pisces: Erythrinidae) of the Neotropical region, Brazil.

Species of fish of Marajó Island, State of Pará, Brazil, were examined to identify the trematodes parasitizing 102 Hoplerytrinus unitaeniatus (gold wolf fish) and 104 Hoplias malabaricus (thraira). Metacercariae of two species of trematodes, 170 specimens of Clinostomatopsis sorbens and 10 Ithyoclinostomum dimorphum were found and identified. The parasitary indices of C. sorbens from H. unitaeniatus and H. malabaricus, were 43.14% and 30.77% for prevalence, 2.52 and 1.84 for mean intensity, 1.09 and 0.57 for mean abundance and 1 to 9 and 1 to 7 for range of infection, respectively, on both fish the site of infection was the mesentery. The parasitary indices of I. dimorphum from H. unitaeniatus were 2.94% for prevalence, 2.66 for mean intensity, 0.08 for mean abundance, 1 to 4 for range of infection, and the sites of infection were the mesentery and the muscle. Metacercariae of I. dimorphum were collected in muscles of a specimen of H. malabaricus, with 0.96% of prevalence, intensity of infection of 2 parasites and 0.02 of abundance. New morphological data of external and internal structures are presented. This is the first record of metacercariae of C. sorbens and I. dimorphum in Amazonian fish.