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1.
Folia Parasitol (Praha) ; 712024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39301677

RESUMO

Myxozoans are microscopical parasites widely distributed in fish, with over 2,600 described species, but their actual diversity is still underestimated. Among salmonids, more than 70 myxozoan species have been identified. This study focuses on species of Chloromyxum Mingazzini, 1890 that infect salmonid kidneys, particularly C. majori Yasutake et Wood, 1957 and C. schurovi Shulman et Ieshko, 2003. Despite their similar spore morphology, they exhibit distinct host preferences, tissue affinities and geographical distributions. Chloromyxum schurovi predominantly infects the renal tubules of Salmo salar Linnaues and S. trutta Linnaeus in Europe, while C. majori targets the glomeruli of Oncorhynchus mykiss (Walbaum) and O. tshawytscha (Walbaum) in North America. The sequence data for C. majori and C. schurovi have been either missing or questionable. In our study, we examined the kidneys of two salmonid species for chloromyxid infections, using both morphological and molecular data to characterise Chloromyxum species in salmonids. The sequence of C. schurovi obtained in our study did not match the previously published parasite data. Instead, it clustered as an independent lineage sister to the Paramyxidium Freeman et Kristmundsson, 2018 clade gathering the species from various fish organs, including the urinary tract. Our findings clarified the taxonomic origin of the previous C. schurovi sequence as Myxidium giardi Cépède, 1906, highlighting the risks associated with the presence of myxozoan blood stages in the bloodstream of their fish host and the challenges of non-specific PCR amplification. We redescribe C. schurovi, thus contributing to a better understanding of the diversity and phylogeny of kidney-infecting species of Chloromyxum.


Assuntos
Doenças dos Peixes , Myxozoa , Doenças Parasitárias em Animais , Filogenia , Truta , Animais , Myxozoa/classificação , Myxozoa/genética , Myxozoa/anatomia & histologia , Myxozoa/isolamento & purificação , Doenças dos Peixes/parasitologia , Doenças Parasitárias em Animais/parasitologia , Doenças Parasitárias em Animais/epidemiologia , Truta/parasitologia , Rim/parasitologia
2.
J Parasitol ; 110(4): 393-401, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39169851

RESUMO

Myxospores discovered floating free in the bile of marine fishes from the south-central coast of Vietnam were identified using morphological and molecular methods, leading to the description of 2 new species. Ceratomyxa chauvanminhi n. sp. was detected in 16% (8/50) of cultured barramundi Lates calcarifer (Bloch) specimens, and Ceratomyxa sekoi n. sp. was found in 20% (5/25) of wild largehead hairtail Trichiurus lepturus Linnaeus specimens. The spores of C. chauvanminhi n. sp. are very shallowly ovoid, slightly crescent shaped, and 11.5 ± 0.5 (10.7-12.4) µm thick, 5.8 ± 0.2 (5.4-6.1) µm long, and 5.5 ± 0.2 (5.2-5.7) µm wide. Their posterior angles are slightly concave at 158.7° ± 4.2° (151.3°-164.8°), and they possess 2 equal spherical polar capsules 2.5 ± 0.2 (2.1-2.9) µm in diameter. The spores of C. sekoi n. sp. are 5.6 ± 0.2 (5.0-6.1) µm long, 75.5 ± 4.8 (68.9-90.0) µm thick, and 5.5 ± 0.1 (5.4-5.6) µm wide, with 2 equal, slightly anterior spherical polar capsules 2.1 ± 0.2 (1.7-2.4) µm in diameter. Although C. sekoi n. sp. spores resemble those of species of MyxodavisiaZhao, Zhou, Kent, and Whipps, 2008, characterized by long tapering valves, genetic analyses distinctly place this new species within the Ceratomyxa Thélohan, 1892 lineage. This study contributes to the understanding myxosporean diversity in Vietnamese waters and highlights the difficulty associated with distinguishing between the genera Ceratomyxa and Myxodavisia.


Assuntos
Doenças dos Peixes , Vesícula Biliar , Myxozoa , Doenças Parasitárias em Animais , Perciformes , Filogenia , Animais , Vietnã , Doenças dos Peixes/parasitologia , Doenças dos Peixes/epidemiologia , Myxozoa/classificação , Myxozoa/isolamento & purificação , Myxozoa/genética , Myxozoa/anatomia & histologia , Vesícula Biliar/parasitologia , Perciformes/parasitologia , Doenças Parasitárias em Animais/parasitologia , Doenças Parasitárias em Animais/epidemiologia , Doenças da Vesícula Biliar/parasitologia , Doenças da Vesícula Biliar/veterinária , Peixes/parasitologia , Prevalência , DNA Ribossômico/química , Smegmamorpha/parasitologia
3.
Parasitol Int ; 102: 102918, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38945391

RESUMO

The coastal waters of Vietnam are home to a wide diversity of fishes, but the parasite diversity of these potential hosts is much less well characterized. To begin addressing this knowledge gap, we carried out surveys of myxozoan parasites in fishes collected from Nha Trang Bay in Vietnam's East Sea in 2018-2019. Mugilid fishes were collected in March-April 2018, January-February 2019, and November-December 2019, and examined for myxozoans. Myxospores consistent with those of the genus Ellipsomyxa were found in the gall bladder of four mullet species, and we thoroughly characterized those from Planiliza melinoptera. Myxospores were elliptoid and devoid of striation, with a distinct sinuous suture line. Polar capsules were pyriform and oriented toward the poles of the spore. Morphological features were compared to nominal species and this species from Vietnam was distinct. Phylogenetic analysis based on partial small subunit rDNA sequence revealed that broadly, Ellipsomyxa species split into three phylogenetic lineages, and although in some branches there are groupings by host family, habitat or locality, there are no clear phylogenetic patterns. The new species we encountered in P. melinoptera had a close sister relationship with Ellipsomyxa adlardi, with both species part of a larger subclade within the Ellipsomyxa lineage. Despite this phylogenetic similarity, these species were morphologically distinct, and partial large subunit DNA sequences were only 93% similar to each other. A combination of the morphological characteristics and molecular data suggest that this is an undescribed species and we propose the name Ellipsomyxa gordeyi n. sp.


Assuntos
Doenças dos Peixes , Vesícula Biliar , Myxozoa , Filogenia , Smegmamorpha , Animais , Vietnã , Doenças dos Peixes/parasitologia , Vesícula Biliar/parasitologia , Smegmamorpha/parasitologia , Myxozoa/classificação , Myxozoa/genética , Myxozoa/anatomia & histologia , Myxozoa/isolamento & purificação , Doenças Parasitárias em Animais/parasitologia , Doenças Parasitárias em Animais/epidemiologia , Baías
4.
Syst Parasitol ; 101(3): 37, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700664

RESUMO

A synopsis of Ortholinea Shulman, 1962 (Cnidaria: Myxosporea: Ortholineidae) is presented and identifies 26 nominal species presently allocated within this genus. Species morphological and morphometric features, tissue tropism, type-host, and type-locality are provided from original descriptions. Data from subsequent redescriptions and reports is also given. Accession numbers to sequences deposited in GenBank are indicated when available, and the myxospores were redrawn based on original descriptions. The information gathered shows that Ortholinea infect a wide taxonomic variety of freshwater and marine fish. Nonetheless, the broad host specificity reported for several species is not fully supported by morphological descriptions and requires molecular corroboration. The members of this genus are coelozoic and mainly parasitize the urinary system, with few species occurring in the gallbladder. Ortholinea visakhapatnamensis is the only exception, being histozoic in the visceral peritoneum. Molecular data of the small subunit ribosomal RNA gene (SSU rDNA) is available for about one third of Ortholinea species, with genetic interspecific variation ranging between 1.65% and 29.1%. Phylogenetic analyses reveal Ortholinea to be polyphyletic, with available SSU rDNA sequences clustering within the subclades of the highly heterogenous freshwater urinary clade of the oligochaete-infecting lineage. The life cycles of two Ortholinea species have been clarified based on molecular inferences and identify triactinomyxon actinospores as counterparts, and marine oligochaetes of the family Naididae as permissive hosts to this genus.


Assuntos
Myxozoa , Especificidade da Espécie , Animais , Myxozoa/classificação , Myxozoa/genética , Myxozoa/anatomia & histologia , Filogenia , Especificidade de Hospedeiro , Peixes/parasitologia , DNA Ribossômico/genética
5.
Artigo em Inglês | MEDLINE | ID: mdl-36748489

RESUMO

We describe Ceratomyxa saurida Zhao et al. 2015 and Ceratomyxa mai sp. nov. (Myxozoa: Ceratomyxidae) from the East China Sea. C. saurida was found in the gallbladders of 3/13 specimens of its type host, Saurida elongata Temminck and Schlegel 1846 (Aulopiformes). Myxospore characters were consistent with the original description to which we have added small subunit (SSU) rRNA gene data. C. mai sp. nov. was found in gallbladders of 3/13 specimens of S. elongata and 5/13 specimens of Neobythites sivicola Jordan and Snyder 1901 (Ophidiiformes). Mature myxospores of C. mai sp. nov. were crescentic in sutural view, with a deeply concave posterior angle 142.2±8.2° (125.8‒158.2°) and an arched anterior side. Shell valves were smooth and equal, 20.9±1.9 (17.3‒24.7) µm thick and 9.2±0.5 (8.1‒9.9) µm long, and joined at a straight, thin sutural plane passing between two nematocysts (polar capsules). The nematocysts were equal-sized, pyriform, 2.6±0.2 (2.4‒2.9) µm long and 2.7±0.2 (2.4‒3.3) µm wide, with their tapered ends pointed toward each other, located in the anterior third of the spore. Sequences of the SSU rRNA gene and internal transcribed spacer 1 showed that the isolates of C. mai sp. nov. obtained from S. elongata and N. sivicola were identical. The SSU rRNA gene sequence of C. mai sp. nov. was distinct from all known myxosporeans and clustered with C. saurida, and then with Ceratomyxa filamentosi Kalatzis, Kokkari and Katharios 2013, both of which also infect Aulopiformes fishes.


Assuntos
Doenças dos Peixes , Myxozoa , Doenças Parasitárias em Animais , Animais , Myxozoa/genética , Myxozoa/anatomia & histologia , Filogenia , Análise de Sequência de DNA , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Ácidos Graxos/química , Peixes , China , DNA Ribossômico/genética
6.
Parasitol Int ; 86: 102445, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34481082

RESUMO

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.


Assuntos
Peixes-Gato , Doenças dos Peixes/parasitologia , Interações Hospedeiro-Parasita , Myxozoa/classificação , Animais , Brasil , Myxozoa/anatomia & histologia , Myxozoa/genética , Myxozoa/fisiologia
7.
Parasitol Int ; 85: 102433, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34371156

RESUMO

We described two novel myxozoan parasite species Ceratomyxa argentina n. sp. and Ceratomyxa raneyae n. sp. from the gall bladder of Raneya brasiliensis (Kaup) from the Patagonian coast of Argentina. Both species can be distinguished from other ceratomyxids by myxospore and polar capsule (nematocyst) morphology and morphometry, fish host and geographic locality. Phylogenetic reconstruction using ssrDNA gene sequences showed that the two new species are placed in a long-branching ceratomyxid clade which also include Ceratomyxa appendiculata Thélohan, 1892, Ceratomyxa anko Freeman, Yokoyama and Ogawa, 2008, Ceratomyxa pantherini Gunter, Burger and Adlard, 2010 and Pseudoalataspora kovalevae Kalavati, MacKenzie, Collins, Hemmingsen and Brickle, 2013. This study documents additional biodiversity of marine myxozoans in the South Atlantic, a region still largely unexplored for this group of parasitic cnidarians.


Assuntos
Doenças dos Peixes/parasitologia , Peixes , Myxozoa/classificação , Doenças Parasitárias em Animais/parasitologia , Animais , Argentina , Myxozoa/anatomia & histologia , Myxozoa/genética , Filogenia
8.
Syst Parasitol ; 98(4): 423-441, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34114095

RESUMO

Characterising myxozoan taxa parasitising fish hosts in catfish aquaculture ponds is crucial to understanding myxozoan community dynamics in these diverse and complex ecological systems. This work investigated the myxozoan fauna of the western mosquitofish, Gambusia affinis, a common, incidental species found in catfish aquaculture ponds in the southeastern United States. 598 fish were sampled in May of 2018 and 2019 from the pond facility of the Thad Cochran National Warmwater Aquaculture Center in Stoneville, Mississippi, USA. Fish were examined microscopically using wet mount preparations of fresh tissue and histology for myxozoans. 18S rRNA gene sequences were amplified from myxospores obtained at necropsy. Updated morphologic, histologic, and 18S rRNA gene sequence features are provided for Henneguya gambusi, Myxobolus pharyngeus, and Myxidium phyllium. Two potentially novel myxozoans were observed during this survey, an undocumented Myxobolus sp. associated with chondrolysis of bones throughout the body and a putative Myxobilatus sp. observed histologically in the renal tubules, ureters, and urinary bladder. However, inadequate samples were obtained for proper species descriptions. Lastly, the life cycle of M. pharyngeus, which is thought to utilize the oligochaete worm Dero digitata as their definitive host, was putatively confirmed by 18S rRNA sequence matching to actinospore stages from oligochaetes in catfish ponds in Mississippi. This work provides novel and expanded morphologic, histologic, molecular and biologic data of five myxozoan parasites of G. affinis, expanding our knowledge of myxozoan diversity in catfish aquaculture ponds.


Assuntos
Ciprinodontiformes/parasitologia , Myxozoa/classificação , Animais , Estágios do Ciclo de Vida , Mississippi , Myxozoa/anatomia & histologia , Myxozoa/genética , Lagoas , RNA Ribossômico 18S/genética , Especificidade da Espécie
9.
Parasitol Res ; 120(7): 2493-2503, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34115215

RESUMO

Recent anecdotal reports from seafood processors in eastern Australia have described an increased occurrence of post-mortem myoliquefaction ('jellymeat') in broadbill swordfish Xiphias gladius, and macroscopic cysts throughout the musculature of yellowfin tuna Thunnus albacares. A genus of parasitic cnidarians, Kudoa (Myxosporea, Multivalvulida), species of which are known to occur in economically important wild-caught fish species globally, can cause similar quality-deterioration issues. However, Kudoa sp. epizootiology within commercially harvested, high-value fish caught within Australia is poorly understood, despite the parasite's economic importance. To determine the causative agent responsible for the observed quality deterioration in swordfish and yellowfin tuna, muscle-tissue samples from seafood processors in Mooloolaba, Australia, collected from October 2019-February 2020, were examined for parasitic infection. Kudoid myxospores were identified from both hosts and were subquadrate in shape, with four equal-sized polar capsules. The SSU rDNA sequences from both fish shared > 99% identity to Kudoa species. Kudoa musculoliquefaciens was isolated from 87.1% of swordfish sampled, suggesting that it is a widespread parasite in swordfish from the southwest Pacific Ocean. This study provides the first molecular and morphological characterisation of Kudoa thunni in yellowfin tuna and K. musculoliquefaciens in swordfish harvested from the waters of eastern Australia, expanding the geographical distribution of K. thunni and K. musculoliquefaciens to include the Coral and Tasman Seas. We demonstrate that not all infected swordfish progress to jellymeat, show the usefulness of molecular tools for reliably identifying infection by Kudoa spp., and add to the overall knowledge of kudoid epizootiology in wild-caught fish.


Assuntos
Peixes/parasitologia , Myxozoa/classificação , Atum/parasitologia , Animais , Austrália , DNA Ribossômico/genética , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , Músculos/parasitologia , Myxozoa/anatomia & histologia , Myxozoa/genética , Oceano Pacífico , Doenças Parasitárias em Animais/epidemiologia , Doenças Parasitárias em Animais/parasitologia , Filogenia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Alimentos Marinhos/parasitologia , Especificidade da Espécie
10.
Parasitol Res ; 120(7): 2379-2389, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33978834

RESUMO

An examination of 18 fishes caught in the South China Sea detected two Unicapsula spp. in the myofibers of the trunk muscles of carangid fishes: Unicapsula aequilobata n. sp. in the Japanese scad, Decapterus maruadsi, and Unicapsula seriolae in the yellowstripe scad, Selaroides leptolepis. They formed thin filamentous pseudocysts of 0.9-2.0 (mean 1.4) mm by 0.03-0.06 (0.04) mm (n = 5) and 0.9-3.4 (2.1) mm by 0.02-0.05 (0.04) mm (n = 12), respectively. Myxospores of U. aequilobata n. sp. are composed of three equal shell valves and measured 6.7-8.5 (7.3) µm in length and 7.1-8.8 (7.6) µm in width, and contained a prominent polar capsule (PC) 3.2-3.8 (3.6) µm in diameter (n = 18) and two rudimentary PCs. A nucleotide sequence (5127 bp) of the ribosomal RNA gene (rDNA) array was obtained for the genetic characterization of this new species. Based on morphological and phylogenetic criteria, we erect U. aequilobata n. sp. as the sixteenth species in the genus Unicapsula. Nucleotide sequences of the 18S and 28S rDNA obtained from U. seriolae from the yellowstripe scad were almost identical (99.6-100% or 99.0-99.6%, respectively) to those from fish found in the seawaters around Australia and Japan. Consequently, this is a new host and geographical distribution records for U. seriolae. In addition, we illustrated the predicted secondary structure of the available 5.8S rDNA sequences of multivalvulid species, including those obtained from U. aequilobata n. sp., to assess the significance of interspecific nucleotide variations in this short rDNA unit.


Assuntos
Doenças dos Peixes/parasitologia , Myxozoa/classificação , Doenças Parasitárias em Animais/parasitologia , Animais , Austrália , China , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Ribossômico/isolamento & purificação , Doenças dos Peixes/epidemiologia , Peixes , Japão , Estrutura Molecular , Myxozoa/anatomia & histologia , Myxozoa/genética , Myxozoa/isolamento & purificação , Doenças Parasitárias em Animais/epidemiologia , Filogenia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S/genética , Água do Mar , Análise de Sequência de DNA , Esporos/ultraestrutura
11.
Parasitol Int ; 83: 102360, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33882331

RESUMO

Coelozoic parasites of the family Myxidiidae were observed in fish of the order Characiformes captured in the middle Tocantins River, Maranhão, Brazil, within the transition between the Cerrado savanna biome and the eastern extreme of the Brazilian Amazon Forest. The analysis of the morphological characteristics of the parasites, complemented with a Bayesian phylogenetic analysis, supported the description of new specie Myxidium imperatrizensis n. sp., found parasitising the gallbladder of specimens of the fish Triportheus angulatus. The study is also only the second report of the occurrence of Myxidium parasites in fish of the family Triportheidae in Brazilian rivers. The results of the present study expand the known distribution of the genera Myxidium the basin of the Tocantins River, the largest hydrographic basin located entirely within Brazil, which encompasses parts of both the Cerrado and Amazon biomes.


Assuntos
Caraciformes , Doenças dos Peixes/epidemiologia , Myxozoa/classificação , Doenças Parasitárias em Animais/epidemiologia , Animais , Brasil/epidemiologia , DNA Ribossômico/análise , Doenças dos Peixes/parasitologia , Microscopia Eletrônica de Varredura/veterinária , Myxozoa/anatomia & histologia , Myxozoa/genética , Myxozoa/ultraestrutura , Doenças Parasitárias em Animais/parasitologia , Prevalência , Rios/parasitologia
12.
Parasitol Res ; 120(7): 2445-2453, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33913003

RESUMO

A new species of Ceratomyxa infecting the gallbladder of the marine ornamental fish Acanthurus xanthopterus collected from the Vizhinjam coast of Kerala is described. The parasite exhibited a prevalence of 100%. Mature spores recovered from the gallbladder were slightly crescentic with rounded lateral extremities and possessed convex anterior and slightly concave to straight posterior margins. Spore valves two, equal, joined by a straight and prominent suture. Myxospores measured 5.5 ± 0.6 µm in length and 15.9 ± 2.3 µm in thickness. Polar capsules two, equal, spherical, positioned anteriorly on either sides of the suture, 2.3 ± 0.2 µm long and 2.2 ± 0.2 µm wide. Polar filament with four to five coils, 21.2 ± 0.6 µm when extruded. Posterior angle 173.6 ± 5.2°. Early sporogonic stages and monosporic, disporic, and multisporic plasmodial stages were spherical to irregular in shape, with or without filopodia. Histopathologic analysis revealed that spores and developing stages were attached to the gallbladder wall as well as found free in the lumen. Morphologic and morphometric comparison of the present parasite with known species of Ceratomyxa indicated significant differences. In molecular and phylogenetic analyses, the present myxosporean revealed high divergence with related forms and occupied an independent position within the Ceratomyxa clade with high nodal support. Considering the morphological, morphometric, molecular, and phylogenetic dissimilarities with the previously described species of Ceratomyxa and the differences in host and geographic locations, the present species of myxosporean is treated as new and is named Ceratomyxa xanthopteri n. sp.


Assuntos
Myxozoa/classificação , Perciformes/parasitologia , Filogenia , Animais , Doenças dos Peixes/parasitologia , Peixes , Vesícula Biliar/parasitologia , Índia , Myxozoa/anatomia & histologia , Myxozoa/genética , Doenças Parasitárias em Animais/parasitologia , Especificidade da Espécie , Esporos/citologia
13.
Syst Parasitol ; 98(2): 119-130, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33687653

RESUMO

Henneguya Thélohan, 1892 is the second most species rich genus of myxozoans, with reports from freshwater and marine fish worldwide. In the Great Lakes region of North America, muskellunge Esox masquinongy is an important game fish species that serves as an apex predator in the ecosystems of many inland lakes. The myxozoan fauna of esocid fish, especially muskellunge, remains largely understudied. During fish health assessments, muskellunge were examined for parasitic infections and myxozoan pseudocysts were observed on gill clip wet mounts. When ruptured under pressure, the intralamellar pseudocysts released thousands of myxospores consistent with those of the genus Henneguya. The myxospores were 67.3-96.6 (79.1 ± 5.9) µm in total length. The spore body was 18.6-22.6 (20.9 ± 1.0) µm × 5.4-6.9 (6.3 ± 0.4) µm in valvular view and 3.5-4.0 (3.8 ± 0.3) µm wide in sutural view. The two pyriform polar capsules positioned at the anterior of the spore body were 6.4-7.7 (7.0 ± 0.4) µm × 1.8-2.1 (2.0 ± 0.1) µm and each contained a tightly coiled polar filament with 9-10 turns. Two tapering caudal processes extended from the posterior of the spore body and were 47.3-75.6 (58.3 ± 5.8) µm in length. Histologically, large intralamellar polysporic plasmodia were surrounded by plump pillar cells and a distinct layer of plasma. Mild inflammation was present peripherally, with small numbers of necrotic germinative cells and intraplasmodial phagocytes internally. Ribosomal 18S rRNA gene sequence data were obtained from three gill pseudocysts. The three ~2000-bp sequences were identical, but shared no significant similarity with any publicly available sequence data. Phylogenetic analyses demonstrated sequence data from this Henneguya fell within a well-supported clade of Henneguya spp. reported from northern pike Esox lucius in Europe. Based on the distinct morphological, histological and molecular data, this species is designated as Henneguya michiganensis n. sp. from muskellunge in Michigan, USA.


Assuntos
Esocidae/parasitologia , Brânquias/parasitologia , Myxozoa/classificação , Animais , Great Lakes Region , Myxozoa/anatomia & histologia , Myxozoa/genética , RNA Ribossômico 18S/genética , Especificidade da Espécie
14.
Parasitol Int ; 83: 102319, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33689827

RESUMO

Myxozoans are microscopic cnidarians that mainly parasitize fishes. The present study aimed to describe a new myxozoan parasite from the gills of Boulengerella cuvieri (Spix and Agassiz, 1829) by morphological and molecular analysis. The fish was collected in 2019 at the Pindaíba River, municipality of Cocalinho, Mato Grosso State, Brazil. Whitish and circular plasmodia were found in the primary gill filaments, occupying an intralamellar position, with an average of 0.5 mm in diameter. Henneguya Thélohan, 1892 myxospores found inside the plasmodia were elongated and ellipsoidal, consisting of two long and elliptical shell valves with two long, tapering caudal appendages. Morphometric measurements revealed a total spore length of 36.1 ± 2.0 µm; spore body length of 12.8 ± 0.5 µm; spore width of 4.9 ± 0.3 µm; tail length of 23.3 ± 1.6 µm; capsule length of 7.2 ± 0.4 µm; capsule width of 1.5 ± 0.2 µm; and 10 coils in the polar filament. Phylogenetic analysis showed that the isolates from this study were grouped into the main-clade of freshwater fishes, within a group of species parasitizing fishes from Brazil. Intergenotypic difference ranged from 23%-25.9% compared with other Brazilian myxozoan isolates. Using molecular and morphological characterization, this parasite was identified as a new species of the genus Henneguya.


Assuntos
Caraciformes , Doenças dos Peixes/parasitologia , Myxozoa/classificação , Doenças Parasitárias em Animais/parasitologia , Animais , Brasil , Água Doce/parasitologia , Brânquias/parasitologia , Myxozoa/anatomia & histologia , Myxozoa/genética , Filogenia , Esporos/isolamento & purificação
15.
J Parasitol ; 107(1): 39-47, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33535231

RESUMO

Few studies have examined community structure among myxozoan species in fish. Herein myxozoan communities are described from 2 cyprinid species, the spottail shiner (Notropis hudsonius) and the common shiner (Luxilus cornutus), from mesotrophic and eutrophic localities in rivers in southwestern Quebec, Canada. Four myxozoan species were found, and total prevalence ranged from 60 to 86.7% in spottail shiners at 4 localities along the Richelieu River. Component species richness ranged from 2 to 4 and mean infracommunity richness from 0.87 to 1.47. Prevalence, component species richness, and infracommunity species richness in the spottail shiner were comparable to those from other localities in the Great Lakes and St. Lawrence River that were exposed to municipal effluents. Nine myxozoan species were found in common shiners from the Bras d'Henri micro-watershed. Component species richness varied from 6 to 8 at 4 localities, with total prevalence being 100% at all localities except 1, where it was 80%. Mean infracommunity richness ranged from 1.73 to 2.27. Prevalence, component species richness, and infracommunity species richness in the common shiner from the Bras d'Henri micro-watershed were among the highest observed for myxozoan communities from any host species to date. It is concluded that moderate levels of eutrophication are sufficient to generate species-rich communities of myxozoan parasites in fishes.


Assuntos
Cyprinidae/parasitologia , Doenças dos Peixes/parasitologia , Myxozoa/classificação , Doenças Parasitárias em Animais/parasitologia , Animais , Myxozoa/anatomia & histologia , Myxozoa/isolamento & purificação , Prevalência , Quebeque , Rios
16.
Parasitol Int ; 80: 102184, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32898661

RESUMO

Plasmodia containing myxospores belonging to the genus Henneguya Thélohan, 1892 were found in the gills of Eugerres brasilianus (Cuvier, 1830). Despite the economic importance, few parasitological studies have been done with this species. We describe Henneguya lagunensis n. sp. using morphological and molecular data. The mature myxospores were rounded, measuring 29.1 ± 2.2 µm in total length, 8.2 ± 1.0 µm in body length, 7.9 ± 0.2 µm in body width, 20.7 ± 2.4 µm in tail length and 4.8 ± 1.0 µm in thickness. The polar capsules measured 3.3 ± 0.4 in length and 1.7 ± 0.3 µm in width. Polar filaments had 4-5 turns, helical. Phylogenetic analysis showed Henneguya lagunensis n. sp. as a sister species of Henneguya cynoscioni Dyková, Buron, Roumillat and Fiala, 2011, within a clade that contained mostly Henneguya species that parasitize marine fish of the order Perciformes. This is the first report of a species of Henneguya parasitizing Eugerres brasilianus.


Assuntos
Doenças dos Peixes/parasitologia , Myxozoa/anatomia & histologia , Myxozoa/genética , Doenças Parasitárias em Animais/parasitologia , Perciformes , Animais , Brasil , DNA de Helmintos/análise , DNA Ribossômico/análise , Filogenia
17.
Syst Parasitol ; 98(1): 25-55, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33201415

RESUMO

A synopsis of the species of Zschokkella Auerbach, 1910 (Myxozoa: Bivalvulida: Myxidiidae) is presented, including 94 nominal species from piscine hosts and 3 additional nominal species from amphibian or reptilian hosts. The most relevant morphological and morphometric features of both myxospores and trophozoite stages (when available) are presented for each species in tabulated format.


Assuntos
Myxozoa/classificação , Anfíbios/parasitologia , Animais , Peixes/parasitologia , Estágios do Ciclo de Vida , Myxozoa/anatomia & histologia , Répteis/parasitologia , Especificidade da Espécie
18.
Parasitol Res ; 119(8): 2431-2438, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32394002

RESUMO

The specimens of Trachinus draco collected from the Bay of Bizerte were found to be infected with a new Ceratomyxa species described as Ceratomyxa draconis n. sp. The sequence of small subunit ribosomal RNA gene obtained in this study differs from other Ceratomyxa sequences available in GenBank. Mature spores of this species were elongated and crescent-shaped in sutural view, measuring 7.4 ± 0.77 (6.4-8.0) µm in thickness and 30.8 ± 1.65 (28.8-32.8) µm in width. The polar capsules were spherical, equal in size, and measuring 3.3 ± 0.2 (3.6-4.0) µm in diameter. The Ceratomyxa draconis n. sp. showed a clearly seasonal variation of prevalence with highest prevalence noted during summer months.


Assuntos
Doenças dos Peixes/parasitologia , Myxozoa , Doenças Parasitárias em Animais/parasitologia , Perciformes/parasitologia , Animais , Baías , DNA Ribossômico/genética , Vesícula Biliar/parasitologia , Myxozoa/anatomia & histologia , Myxozoa/classificação , Myxozoa/genética , Filogenia , Subunidades Ribossômicas Menores/genética , Estações do Ano , Tunísia/epidemiologia
19.
Parasitol Res ; 119(6): 1743-1752, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32318807

RESUMO

A new parasite species, Kudoa yasai n. sp. (Multivalvulida), is described from the king weakfish (Macrodon ancylodon), which is an important commercial fishery resource on the Brazilian Amazon coast. A total of 190 M. ancylodon specimens were obtained from the central fish market of the town of Bragança, and pseudocysts were found in the skeletal muscle fiber samples of all (100%) of the specimens, although no inflammatory reaction was observed in any of the cases. The myxospores are quadrate in shape with four polar capsules of equal size, 6.9 ± 0.94 µm long, 8.2 ± 0.39 µm wide, and 5.5 ± 0.60 µm thick. The polar capsules are 1.8 ± 0.26 µm in length and 1.4 ± 0.18 µm in width. The morphological and morphometric parameters, together with the phylogenetic analysis of a partial sequence of the 18S (SSU rDNA) gene, all indicate conclusively that Kudoa yasai n. sp. is a new species, distinct from all other Kudoa species. The study also verified the loss of quality in the meat of the host fish (M. ancylodon) sold in the Bragança market, which reinforces the need for the more systematic control of the quality of the product and the prevention of possible health problems for the consumer.


Assuntos
Músculo Esquelético/parasitologia , Myxozoa/classificação , Doenças Parasitárias em Animais/parasitologia , Perciformes/parasitologia , Alimentos Marinhos/parasitologia , Animais , Brasil , Myxozoa/anatomia & histologia , Myxozoa/genética , Filogenia , RNA Ribossômico 18S/genética , Análise de Sequência de DNA
20.
Acta Parasitol ; 65(2): 388-395, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32052241

RESUMO

BACKGROUND: Myxidium kudoi Meglitsch, 1937 has been described from the type host, blue catfish Ictalurus furcatus, with no additional host records or molecular data available for this species. PURPOSE: To provide molecular data and a novel host locality for this species and carry out phylogenetic analyses to infer the evolutionary relationship of the species to other members of the family Myxidiidae for which DNA sequence data is available. METHODS: These data were collected using myxospores from the gallbladder of a blue catfish, Ictalurus furcatus collected from Lake Texoma, Oklahoma, USA. Myxospores were morphologically consistent with the only other account of this species and not any other Myxidium species described from siluriform fishes. RESULTS: Myxospores were oblong with rounded ends and were 10.8-12.6 (11.6 ± 0.5) µm in length and 4.7-6.6 (5.7 ± 0.5) µm in width. Polar capsules were subspherical and 2.7-3.9 (3.4 ± 0.3) µm in length and 2.4-3.5 (3.1 ± 0.3) µm in diameter, with each capsule containing a polar filament with 3-4 coils. Molecular data consisted of a 2918-bp sequence of the partial 18S, complete ITS1, 5.8S, ITS2, and partial 28S ribosomal rRNA regions as well as a 2455-bp sequence of partial 28S ribosomal RNA. The partial 18S and 28S data was used in a concatenated Bayesian phylogenetic analysis to further infer the evolutionary relationships of the Myxidiidae. Additionally, the partial 18S data was used in a separate phylogenetic analysis. CONCLUSIONS: The present work reports novel morphological and molecular data for Myxidium kudoi as well as a novel locality of occurrence for this species. In concatenated phylogenetic analysis using 18S and 28S data and other molecular data from Myxozoa, M. kudoi grouped with other freshwater Myxidiidae. In the single-locus, 18S analysis, M. kudoi grouped with Myxidium rhodei from Rutilus rutilus and Myxidium amazonense from Corydoras melini, the only other Myxidium species of catfish for which molecular data are available.


Assuntos
Doenças dos Peixes/parasitologia , Ictaluridae/parasitologia , Myxozoa/anatomia & histologia , Myxozoa/genética , Doenças Parasitárias em Animais/parasitologia , Animais , Teorema de Bayes , Vesícula Biliar/parasitologia , Lagos , Myxozoa/classificação , Oklahoma , Filogenia , RNA Ribossômico 18S/química , RNA Ribossômico 28S/química , Alinhamento de Sequência , Esporos/ultraestrutura
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