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1.
Rev Bras Parasitol Vet ; 29(2): e000620, 2020.
Article in English | MEDLINE | ID: mdl-32609239

ABSTRACT

This study describes Henneguya sacacaensis n. sp. in specimens of the Osteichthyes Satanoperca jurupari (Heckel, 1840), collected in the Rio Curiaú Environmental Protection Area in the city of Macapá, state of Amapá Brazil. Using optical microscopy and molecular analysis, these cyst-shaped parasites were analyzed. The gills of 57.14% of the analyzed S. jurupari contained hundreds of spores. The cysts found on the gill lamellae were oval-shaped and whitish. The Henneguya spores had an average length of 46.5 (41.3-56.92) µm. The fusiform body of the Henneguya measured 16.5 (13.16-20.01) µm long and 5.1 (3.91-6.12) µm in width, the two polar capsules had a taper of 3.83 (3.4-4.32) µm and a width of 1.68 (1.4-1.99) µm, and the tail measured 30 (22.47-41.67) µm in length, containing a polar filament coiled seven to nine times. Morphogical and phylogenetic analysis allowed the preposition of a new species, Henneguya sacacaensis n. sp, that belongs to the family Myxobolidae and the genus Henneguya.


Subject(s)
Cichlids , Fish Diseases , Myxozoa , Parasitic Diseases, Animal , Animals , Brazil , Cichlids/parasitology , Fish Diseases/parasitology , Gills/parasitology , Myxozoa/classification , Myxozoa/cytology , Myxozoa/genetics , Parasitic Diseases, Animal/parasitology , Phylogeny , Species Specificity
2.
Parasitol Res ; 119(3): 871-878, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31897794

ABSTRACT

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.


Subject(s)
Characiformes/parasitology , Fish Diseases/parasitology , Myxozoa/physiology , Parasitic Diseases, Animal/parasitology , Plasmodium/parasitology , Animals , Brazil , Fresh Water/parasitology , Gallbladder/parasitology , Myxozoa/classification , Myxozoa/cytology , Myxozoa/genetics , Phylogeny , Plasmodium/physiology
3.
Rev. bras. parasitol. vet ; 29(2): e000620, 2020. tab, graf
Article in English | LILACS | ID: biblio-1138063

ABSTRACT

Abstract This study describes Henneguya sacacaensis n. sp. in specimens of the Osteichthyes Satanoperca jurupari (Heckel, 1840), collected in the Rio Curiaú Environmental Protection Area in the city of Macapá, state of Amapá Brazil. Using optical microscopy and molecular analysis, these cyst-shaped parasites were analyzed. The gills of 57.14% of the analyzed S. jurupari contained hundreds of spores. The cysts found on the gill lamellae were oval-shaped and whitish. The Henneguya spores had an average length of 46.5 (41.3-56.92) µm. The fusiform body of the Henneguya measured 16.5 (13.16-20.01) µm long and 5.1 (3.91-6.12) µm in width, the two polar capsules had a taper of 3.83 (3.4-4.32) µm and a width of 1.68 (1.4-1.99) µm, and the tail measured 30 (22.47-41.67) µm in length, containing a polar filament coiled seven to nine times. Morphogical and phylogenetic analysis allowed the preposition of a new species, Henneguya sacacaensis n. sp, that belongs to the family Myxobolidae and the genus Henneguya.


Resumo Henneguya sacacaensis n. sp. é descrito em espécimes do Osteichthyes Satanoperca jurupari (Heckel, 1840), coletados na área de Proteção Ambiental do rio Curiaú na cidade de Macapá no estado do Amapá, Brasil. Com auxílio de microscopia óptica e análises moleculares, esses parasitos foram analisados e observados nas brânquias em forma de cistos, contendo centenas de esporos e apresentaram a prevalência de 57,14%. Os cistos encontrados nas lamelas branquiais tinham formatos ovais e esbranquiçados. Seus esporos apresentaram um comprimento médio de 46,5 (41,3-56,92) µm, corpo fusiforme medindo 16,5 (13,16-20,01) µm de comprimento e 5,1 (3,91-6,12) µm de largura, suas duas cápsulas polares apresentam uma conicidade de 3,83 (3,4-4,32) µm e sua largura 1,68 µm (1,4-1,99), a cauda 30 (22,47-41,67) µm de comprimento, contento um filamento polar de 7 à 9 voltas. Análises morfológicas e filogenéticas permitiram a preposição de uma nova espécie, Henneguya sacacaensis n. sp, que pertence à família Myxobolidae e ao gênero Henneguya.


Subject(s)
Animals , Parasitic Diseases, Animal/parasitology , Cichlids/parasitology , Myxozoa/cytology , Myxozoa/classification , Myxozoa/genetics , Fish Diseases/parasitology , Phylogeny , Species Specificity , Brazil , Gills/parasitology
4.
Parasitol Res ; 118(12): 3327-3336, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31728724

ABSTRACT

On the basis of morphological and molecular analyses, a new myxozoan parasite is described from the gills of the fish Hoplerythrinus unitaeniatus, collected in the municipality of Nova Xavantina, Mato Grosso State, Brazil. Plasmodia of Henneguya unitaeniata sp. nov. were oval and whitish and were found surrounded by collagen fibers forming plasmodia wall between gill filaments on the gill arch. The spores were ellipsoidal with two similar polar capsules. Morphometric analysis showed a total spore mean length of 23.8 ± 1.5 µm, spore body mean length of 14.5 ± 0.7 µm, caudal appendage mean length of 10.3 ± 1.4 µm, thickness mean length of 4.3 ± 0.3 µm, polar capsule mean length of 4.2 ± 0.5 µm, polar capsule mean width of 1.8 ± 0.3 µm, spore mean width of 4.8 ± 0.4 µm, and 4-5 polar filament coils. Phylogenetic analysis showed Henneguya unitaeniata sp. nov. as a basal species in a subclade formed by myxozoans that parasitize bryconid fishes.


Subject(s)
Characiformes/parasitology , Gills/parasitology , Myxozoa/classification , Myxozoa/growth & development , Phylogeny , Animals , Brazil , Life Cycle Stages , Myxozoa/cytology , Myxozoa/genetics , Species Specificity
5.
Rev Bras Parasitol Vet ; 28(3): 416-424, 2019 Jul 29.
Article in English | MEDLINE | ID: mdl-31365719

ABSTRACT

The aim of this was describe an infection by Kudoa orbicularis in freshwater catfish Trachelyopterus galeatus. A sample of 80 specimens of T. galeatus was collected in the municipality of Cachoeira do Arari, Marajó Island, in the state of Pará, Brazil. Pseudocysts were found in the muscle fibers of the epaxial and hypaxial regions of 85.0% of the specimens analyzed, reflecting a high infection rate. The pseudocysts contained spores that were pseudo-square in shape, with a mean length of 4.65 µm (range: 4.04-5.54) and mean width of 1.53 µm (1.56-1.74). Analyses on the morphology of the spores and a partial 934-bp sequence of the SSU rDNA gene confirmed that the microparasite was Kudoa orbicularis. This is the second record of this microparasite in a siluriform host in the Brazilian Amazon region.


Subject(s)
Catfishes/parasitology , Fish Diseases/parasitology , Myxozoa/isolation & purification , Animals , Brazil , DNA, Ribosomal/genetics , Fish Diseases/diagnosis , Fresh Water , Myxozoa/cytology , Myxozoa/genetics , Phylogeny , Polymerase Chain Reaction
6.
Rev. bras. parasitol. vet ; 28(3): 416-424, July-Sept. 2019. tab, graf
Article in English | LILACS | ID: biblio-1042514

ABSTRACT

Abstract The aim of this was describe an infection by Kudoa orbicularis in freshwater catfish Trachelyopterus galeatus. A sample of 80 specimens of T. galeatus was collected in the municipality of Cachoeira do Arari, Marajó Island, in the state of Pará, Brazil. Pseudocysts were found in the muscle fibers of the epaxial and hypaxial regions of 85.0% of the specimens analyzed, reflecting a high infection rate. The pseudocysts contained spores that were pseudo-square in shape, with a mean length of 4.65 µm (range: 4.04-5.54) and mean width of 1.53 µm (1.56-1.74). Analyses on the morphology of the spores and a partial 934-bp sequence of the SSU rDNA gene confirmed that the microparasite was Kudoa orbicularis. This is the second record of this microparasite in a siluriform host in the Brazilian Amazon region.


Resumo O objetivo deste estudo foi descrever a infecção por Kudoa orbicularis em Trachelyopterus galeatus. Foram analisados 80 espécimes de T. galeatus capturados no município de Cachoeira do Arari, ilha de Marajó, estado do Pará, Brasil. A presença de pseudocistos nas fibras musculares das regiões epiaxial e hipoaxial em 85,0% dos exemplares analisados, mostra alto grau de infecção. Os pseudocistos continham esporos de formato pseudoquadrado, medindo 4,65 (4,04-5,54) µm de comprimento e 5,25 (4,78-5,98) µm de largura, com quatro cápsulas polares de tamanho iguais medindo 2,22 (2,05-2,32) µm de comprimento e 1,53 (1,56-1,74) µm de largura. Através das análises morfológicas dos esporos e molecular de uma sequência parcial de 934bps do gene SSU rDNA, confirma que o microparasito é Kudoa orbicularis, sendo este o segundo registro desse microparasito em hospedeiro da ordem Siluriformes da Amazônia brasileira.


Subject(s)
Animals , Catfishes/parasitology , Myxozoa/isolation & purification , Fish Diseases/parasitology , Phylogeny , Brazil , DNA, Ribosomal/genetics , Polymerase Chain Reaction , Myxozoa/cytology , Myxozoa/genetics , Fish Diseases/diagnosis , Fresh Water
7.
Microb Pathog ; 128: 294-300, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30660739

ABSTRACT

A new myxozoan species, Henneguya sp., is described based on material from skin of Cyphocharax modestus. Mature myxospores are were elongate and ellipsoidal, measuring 21.4 ±â€¯1.2 (19.4-23.2) µm in total length, 5.1 ±â€¯0.3 (4.5-5.8) µm in width, 11.9 ±â€¯0.5 (10.9-12.7) µm in body length and 9.6 ±â€¯0.7 (8.4-10.5) µm in length of the caudal process. The polar capsules were elongated and had unequal sizes, with length of 5.1 ±â€¯0.4 (4.5-6.0) µm and 5.6 ±â€¯0.4 (4.9-6.3) µm for smaller and larger respectively and width of 1.8 ±â€¯0.2 (1.4-2.0) µm. The larger polar capsule had 8 turns in polar filament while the smaller polar capsule had 5 turns in polar filament. The macroscopic analysis revealed the presence of large nodules, which were located before and after the dorsal fin of the hosts. The histopathological analysis showed the development of nodules filled with plasmodia, surrounded by loose connective tissue, developed in the dermis of the skin. Many cysts containing countless spores, as well as free spores, were located in the dermis and hypodermis of the hosts, causing the disorganization of the connective tissue that is responsible for the support. This is the first record of a Henneguya species in C. modestus.


Subject(s)
Characiformes/parasitology , Fishes/parasitology , Myxozoa/isolation & purification , Myxozoa/pathogenicity , Parasitic Diseases, Animal/parasitology , Skin/parasitology , Symbiosis , Animals , Brazil , Myxozoa/anatomy & histology , Myxozoa/cytology , Parasitic Diseases, Animal/pathology , Phylogeny , Rivers , Seafood/parasitology , Species Specificity , Spores , Subcutaneous Tissue/parasitology , Subcutaneous Tissue/pathology
8.
Microb Pathog ; 123: 372-376, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30055245

ABSTRACT

Molecular data of Henneguya chydadea Barassa, Cordeiro and Arana, 2003, found in the gill filaments of Astyanax lacustris bred in fish farm in the State of Mato Grosso do Sul, Brazil was obtained in order to estimate their phylogenetic position among other platysporines myxosporean. The prevalence of the parasite was 28.1% and the range intensity was 1-3 plasmodia per fish. The shape and measurements of mature myxospores were consistent with the characteristics previously defined to H. chydadea. The SSU rDNA sequence of the myxospores of H. chydadea resulted in a total of 1405 nucleotides, and this sequence did not match any of the myxozoan available in the GenBank. Phylogenetic analysis showed H. chydadea within the clade of histozoic myxosporeans and closed together with Henneguya rotunda and Myxobolus pantanalis reported in the gill arch and fins and gill filaments of Salminus brasiliensis respectively. Nonetheless, the SSU rDNA sequences of H. chydadea, H. rotunda and M. pantanalis have only 85.2% and 84.4% similarity, respectively. This is the first molecular study of a Henneguya species that parasitizes a fish belonging to the genus Astyanax in South America. The importance of myxosporeans introduction to new locations along with infected cultured host is emphasized.


Subject(s)
Characidae/parasitology , Fish Diseases/parasitology , Gills/parasitology , Myxozoa/classification , Myxozoa/genetics , Phylogeny , Animals , Aquaculture , Base Sequence , Brazil/epidemiology , DNA, Protozoan/genetics , DNA, Ribosomal/genetics , Databases, Nucleic Acid , Fish Diseases/epidemiology , Fisheries , Molecular Typing , Myxozoa/cytology , Parasites/classification , Parasites/genetics , Prevalence
9.
Acta Parasitol ; 63(3): 495-503, 2018 Sep 25.
Article in English | MEDLINE | ID: mdl-29975658

ABSTRACT

During a parasitological survey of Astyanax altiparanae captured in the Mogi Guaçú river, Pirassununga, state of São Paulo, Brazil, a new species of myxozoa was observed infecting the kidney of 30 of 42 specimens. Plasmodia of the new myxozoa, referred to herein as Unicauda whippsi n. sp. were spherical and varied from 450 to 1000 µm in length. The mature spore was elongated and measured 11 ± 1.2 (10-12) µm long by 5.4 ± 0.6 (4.7-7.2) µm wide. Polar capsules of unequal length with the filament coiled 7-9 times and a unique caudal process characteristic of the genus Unicauda, were recorded. Phylogenetic analysis demonstrated that U. whippsi n. sp. clustered with members of the genus Unicauda and Myxobolus, confirming it's placement within the family Myxobolidae. This is the first record of a species of Unicauda infecting characiform fish, as well as the first registered occurrence of species of this genus in South America.


Subject(s)
Characidae/parasitology , Fish Diseases/parasitology , Myxozoa/classification , Parasitic Diseases, Animal/parasitology , Animals , Brazil , Kidney/parasitology , Myxobolus/classification , Myxobolus/cytology , Myxobolus/genetics , Myxobolus/isolation & purification , Myxozoa/cytology , Myxozoa/genetics , Myxozoa/isolation & purification , Phylogeny , Rivers/parasitology , Spores
10.
Acta Parasitol ; 60(3): 442-50, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26204181

ABSTRACT

Through morphological, histopathological and ultrastructural analysis of Myxobolus cuneus Adriano, Arana et Cordeiro, 2006 and Henneguya pseudoplatystoma Naldoni, Arana, Maia, Ceccarelli, Tavares, Borges, Pozo et Adriano, 2009 were identified infecting pacu respectively (Piaractus mesopotamicus) and hybrid pintado (Pseudoplatystoma corruscans x Pseudoplatystoma reticulatum) taken from Brazilian fish farms. The present study describes 18S rDNA sequencing of Myxobolus cf. cuneus infecting the spleen of farmed patinga, a hybrid fish resulting from the crossing of P. mesopotamicus x Piaractus brachypomus, and H. pseudoplatystoma found in farmed hybrid pintado from the state of Sao Paulo, Brazil. The study also provides new details of the host-parasite interface of M. cf. cuneus, which reveal that the plasmodial wall is composed of a single membrane connected to the plasmodium ectoplasm by numerous pinocytic canals. The plasmodia also displayed asynchronous development but had disporic pansporoblasts at different developmental stages; immature and mature spores were found at different depth levels of the plasmodium. Maximum likelihood phylogenetic analysis showed that M. cf. cuneus appeared as a sister species of Henneguya pellucida Adriano, Arana et Cordeiro, 2005 in a sub-clade composed mainly of myxosporean parasites of characiforms, and that H. pseudoplatystoma clustered in a sub-clade composed of Henneguya/Myxobolus spp. parasites of siluriform fish.


Subject(s)
Fish Diseases/parasitology , Myxozoa/classification , Myxozoa/isolation & purification , Parasitic Diseases, Animal/parasitology , Animals , Brazil , Catfishes/parasitology , Characiformes/parasitology , Chimera/parasitology , Cluster Analysis , DNA, Protozoan/chemistry , DNA, Protozoan/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Fish Diseases/pathology , Microscopy , Molecular Sequence Data , Myxozoa/cytology , Myxozoa/genetics , Parasitic Diseases, Animal/pathology , Phylogeny , RNA, Ribosomal, 18S/genetics , Sequence Analysis, DNA , Spleen/parasitology
11.
Acta Parasitol ; 60(3): 451-8, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26204182

ABSTRACT

Henneguya leporinicola is a parasite of the gill filament of Leporinus macrocephalus, a characiform fish belonging to the Anostomidae family, which is of major economic importance. Despite the damage it causes in fish, little is known about this parasite. Therefore, a study was undertaken with fourteen specimens of L. macrocephalus taken from fish farms in the state of Sao Paulo. The fish were collected and examined searching for lesions and/or myxosporean plasmodia. One of the specimens (7.14%) contained white elongated plasmodia in the gill filament. The mature spores had elongated bodies with polar capsules of equal size and a caudal length greater than body length. Morphological characteristics identified the parasite as H. leporinicola. Molecular analysis of the 18S rDNA sequence resulted in a 1954 bp, demonstrating significant genetic differences with previously described species of Henneguya/Myxobolus. Phylogenetic analysis comparing the 18S rDNA sequence of H. leporinicola with other species, previously described in South America, and the 20 closest species as indicated by BLASTn Max Score showed H. leporinicola as a basal branch of a subclade composed by Henneguya spp. parasite of characiform hosts.


Subject(s)
Characiformes/parasitology , Fish Diseases/parasitology , Myxozoa/classification , Myxozoa/isolation & purification , Parasitic Diseases, Animal/parasitology , Animals , Aquaculture , Brazil , Cluster Analysis , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Fish Diseases/pathology , Gills/parasitology , Gills/pathology , Histocytochemistry , Microscopy , Molecular Sequence Data , Myxozoa/cytology , Myxozoa/genetics , Parasitic Diseases, Animal/pathology , Phylogeny , RNA, Ribosomal, 18S/genetics , Sequence Analysis, DNA
12.
Parasitol Res ; 113(5): 1703-11, 2014 May.
Article in English | MEDLINE | ID: mdl-24535737

ABSTRACT

A new species of myxosporea (Henneguya rotunda n. sp.) was found in the membrane of the gill arch and the fins of Salminus brasiliensis in the Mogi Guaçu River, municipality of Pirassununga, São Paulo state, Brazil. Morphological and morphometric analyses using light microscopy revealed parasites with similar characteristics at both infection sites. The mature spores found infecting the fins had oval spore body with 7.1 ± 0.2 µm in length, 5.6 ± 0.2 µm in width, 3.7 ± 0.1 µm in thickness, 16.4 ± 1.2 µm in length of the caudal process, and 23.6 ± 1.1 µm in total length of the spore. In a frontal view, the polar capsule was observed to be symmetrical with 3.4 ± 0.2 µm in length and 1.8 ± 0.1 µm in width. Mature spores contain six to seven turns of the polar filaments. The morphometric data concerning the spores obtained from plasmodia from the membrane of the gill arch were similar to those from the fins. Ultrastructure analysis revealed that the plasmodial wall was formed by a single membrane and had numerous pinocytotic canals connecting the outside of the plasmodia to the ectoplasm zone. Beyond that, various electron-translucent vesicles also were observed at the periphery of the plasmodium. The molecular analyses of the 18S rDNA gene from the spores obtained from the gill arch membrane and fin membrane showed that these sequences shared 100% similarity. Phylogenetic studies using maximum parsimony and maximum likelihood methods demonstrated the polyphyletic clustering of the myxosporean parasites of characiform fishes. H. rotunda n. sp. clustered as a sister species of Myxobolus pantanalis, also a parasite of S. brasiliensis.


Subject(s)
Animal Fins/parasitology , Characiformes/parasitology , Fish Diseases/parasitology , Gills/parasitology , Myxozoa/classification , Myxozoa/ultrastructure , Animals , Brazil , Myxozoa/cytology , Phylogeny , RNA, Ribosomal, 18S/genetics , Rivers
13.
Parasitol Res ; 110(2): 887-94, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21842391

ABSTRACT

Henneguya azevedoi n. sp. is described from the piava (Leporinus obtusidens). Between 2005 and 2007, 60 fish were collected from the Mogi-Guaçu River near Cachoeira de Emas Falls located in the municipality of Pirassununga, state of São Paulo, Brazil. A total of 70% had plasmodia of the parasite. The plasmodia were white, spherical, and measured 40-200 µm in diameter. Histopathological analysis revealed that the development of the parasite was intralamellar and caused stretching of the epithelium, with accentuated deformation, as well as compression of the capillary and adjacent tissues. Ultrastructural analysis revealed that the wall of the plasmodium was a single membrane in direct contact with the host cells and contained pinocytic canals that extended into the plasmodium. The development of the parasite was asynchronous, with the earliest stages at the periphery and mature spores in the central region. Mature spores were elongated in the frontal view [mean ± standard deviation (range)]: 45.2 ± 0.6 (45.0-47.0) µm in total length, 10.0 ± 0.07 (9.9-10.2) µm in body length, 35.6 ± 0.9 (34.9-36.5) µm in caudal process length, and 4.4 ± 0.4 (4.0-5.0) µm in body width. The polar capsules were elongated and equal in size: 3.8 ± 0.3 (3.5-4.0) µm in length and 1.0 µm in width. The polar filaments were coiled in six to seven turns and perpendicular to the axis of the capsule. Scanning electron microscopy revealed smooth valves and a conspicuous rim around the spore body. This is the first time that a myxosporean has been reported in L. obtusidens.


Subject(s)
Characiformes/parasitology , Fish Diseases/parasitology , Gills/parasitology , Host-Parasite Interactions , Myxozoa/cytology , Myxozoa/pathogenicity , Parasitic Diseases, Animal/parasitology , Animals , Brazil , Fish Diseases/pathology , Histocytochemistry , Microscopy, Electron , Myxozoa/ultrastructure , Parasitic Diseases, Animal/pathology , Rivers
14.
J Eukaryot Microbiol ; 58(6): 525-8, 2011.
Article in English | MEDLINE | ID: mdl-21895844

ABSTRACT

Meglitschia mylei n. sp. found in the gall bladder of the teleostean fish Myleus rubripinnis (Serrasalmidae) from the middle Amazonian region of Brazil is described using light and transmission electron microscopy. The spores observed in the bile averaged 24.6±0.8 µm long, 8.7±0.4 µm wide and 5.1±0.3 µm thick and were strongly furcate and arcuate ∩-shaped composed of two symmetric equal-sized valves, up to ∼70 nm thick. Each valve possessed one opposed tapering appendage, 20.1±0.7 µm long, oriented parallel towards the basal tip of the appendages and joined along a right suture line forming a thick strand. The strand goes around the central part of the spore, which in turn surrounds two equal and symmetric spherical polar capsules (PC), 2.1±0.3 µm in diameter, located at the same level. Each capsule contains a polar filament with five (rarely six) coils. The binucleate sporoplasm was irregular in shape, contained several sporoplasmosomes, ∼175 nm in diameter and filled all the space of the two caudal appendages. Based on the arc shape of the spore with two tapering caudal appendages oriented to the basis of spores, on the number and position of the PC and of the polar filament coils and arrangements, and on the host specificity, we propose the name M. mylei n. sp. for this new myxozoan. Accordingly, this is the second described species of this genus.


Subject(s)
Characidae/parasitology , Myxozoa/cytology , Myxozoa/isolation & purification , Animals , Brazil , Female , Gallbladder/parasitology , Male , Microscopy/methods , Organelles/ultrastructure , Rivers , Spores, Protozoan/cytology
15.
PLoS One ; 6(4): e18871, 2011 Apr 25.
Article in English | MEDLINE | ID: mdl-21541340

ABSTRACT

Infectious diseases are contributing to the decline of endangered amphibians. We identified myxosporean parasites, Myxidium spp. (Myxosporea: Myxozoa), in the brain and liver of declining native frogs, the Green and Golden Bell frog (Litoria aurea) and the Southern Bell frog (Litoria raniformis). We unequivocally identified two Myxidium spp. (both generalist) affecting Australian native frogs and the invasive Cane toad (Bufo marinus, syn. Rhinella marina) and demonstrated their association with disease. Our study tested the identity of Myxidium spp. within native frogs and the invasive Cane toad (brought to Australia in 1935, via Hawaii) to resolve the question whether the Cane toad introduced them to Australia. We showed that the Australian brain and liver Myxidium spp. differed 9%, 7%, 34% and 37% at the small subunit rDNA, large subunit rDNA, internal transcribed spacers 1 and 2, but were distinct from Myxidium cf. immersum from Cane toads in Brazil. Plotting minimum within-group distance against maximum intra-group distance confirmed their independent evolutionary trajectory. Transmission electron microscopy revealed that the brain stages localize inside axons. Myxospores were morphologically indistinguishable, therefore genetic characterisation was necessary to recognise these cryptic species. It is unlikely that the Cane toad brought the myxosporean parasites to Australia, because the parasites were not found in 261 Hawaiian Cane toads. Instead, these data support the enemy-release hypothesis predicting that not all parasites are translocated with their hosts and suggest that the Cane toad may have played an important spill-back role in their emergence and facilitated their dissemination. This work emphasizes the importance of accurate species identification of pathogens relevant to wildlife management and disease control. In our case it is paving the road for the spill-back role of the Cane toad and the parasite emergence.


Subject(s)
Anura/parasitology , Introduced Species , Myxozoa/physiology , Parasites/physiology , Parasitic Diseases, Animal/parasitology , Animals , Anura/growth & development , Australia , Axons/parasitology , Axons/pathology , Brain/parasitology , Brain/pathology , Brain/ultrastructure , Brazil , DNA, Ribosomal/genetics , Endangered Species , Genotype , Geography , Hawaii , Larva/parasitology , Larva/ultrastructure , Life Cycle Stages , Liver/parasitology , Liver/pathology , Liver/ultrastructure , Molecular Sequence Data , Myelin Sheath/parasitology , Myxozoa/cytology , Myxozoa/genetics , Parasites/cytology , Parasites/genetics , Phylogeny
16.
Eur J Protistol ; 45(2): 139-46, 2009 May.
Article in English | MEDLINE | ID: mdl-19211236

ABSTRACT

A myxosporidian was found in the urinary bladder of the teleost Menticirrhus americanus Linnaeus, 1758 (Sciaenidae) collected from the South Atlantic coast of Brazil. Polysporic amoeboid plasmodia containing sporoblasts, developing pansporoblasts and spores were free in the bladder lumen. The prevalence of infection was 17.64% (15/85). Unfixed spores were spherical to subspherical, on average 10.5microm long, 9.8microm wide and 10.1microm thick (n=25), and fixed spores measured 10.1 x 9.5 x 9.7microm. The two spore valves were of equal size and each possessed prominent sutural lines and about 41 (37-45) surface ridges aligned parallel with the suture line. These ridges gave transverse sections a cog-wheel-like outline. The spores contained four pyriform polar capsules of equal size (3.20 x 2.0microm) (n=25) (fixed), each with a polar filament having 3-4 (rarely 5) coils. The binucleate sporoplasm was irregular in shape, with granular matrix and randomly distributed dense bodies. The shape and dimensions of the spore, as well as the number, position and arrangement of the surface ridges, polar capsules and polar filament indicate that this is a new species, herein designated Chloromyxum menticirrhi. The gill, liver, gall bladder and intestine of the host showed no abnormalities.


Subject(s)
Fish Diseases/parasitology , Myxozoa/classification , Myxozoa/ultrastructure , Parasitic Diseases, Animal/parasitology , Perciformes/parasitology , Urinary Bladder/parasitology , Animals , Brazil , Life Cycle Stages , Marine Biology , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Myxozoa/cytology , Myxozoa/physiology , Spores, Protozoan/cytology
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