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1.
Parasitol Res ; 120(2): 525-534, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33415389

RESUMO

The species Metchnikovella dogieli (Paskerova et al. Protistology 10:148-157, 2016) belongs to one of the early diverging microsporidian groups, the metchnikovellids (Microsporidia: Metchnikovellidae). In relation to typical ('core') microsporidia, this group is considered primitive. The spores of metchnikovellids have no classical polar sac-anchoring disk complex, no coiled polar tube, no posterior vacuole, and no polaroplast. Instead, they possess a short thick manubrium that expands into a manubrial cistern. These organisms are hyperparasites; they infect gregarines that parasitise marine invertebrates. M. dogieli is a parasite of the archigregarine Selenidium pygospionis (Paskerova et al. Protist 169:826-852, 2018), which parasitises the polychaete Pygospio elegans. This species was discovered in samples collected in the silt littoral zone at the coast of the White Sea, North-West Russia, and was described based on light microscopy. No molecular data are available for this species, and the publicly accessible genomic data for metchnikovellids are limited to two species: M. incurvata Caullery & Mesnil, 1914 and Amphiamblys sp. WSBS2006. In the present study, we applied single-cell genomics methods with whole-genome amplification to perform next-generation sequencing of M. dogieli genomic DNA. We performed a phylogenetic analysis based on the SSU rRNA gene and reconstructed a multigene phylogeny using a concatenated alignment that included 46 conserved single-copy protein domains. The analyses recovered a fully supported clade of metchnikovellids as a basal group to the core microsporidia. Two members of the genus Metchnikovella did not form a clade in our tree. This may indicate that this genus is paraphyletic and requires revision.


Assuntos
Apicomplexa/microbiologia , Microsporídios/genética , Poliquetos/parasitologia , Animais , Evolução Molecular , Genômica , Microsporídios/classificação , Microsporídios/ultraestrutura , Filogenia , Federação Russa , Esporos Fúngicos/ultraestrutura
2.
Eur J Protistol ; 73: 125670, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31968298

RESUMO

Four epibiotic sessilid peritrichs, i.e., Zoothamnium wilberti n. sp., Baikalonis microdiscus n. sp., Epistylis anastatica (Linnaeus, 1767) Ehrenberg, 1830, and Rhabdostyla commensalisMöbius, 1888, were isolated from one syllid polychaete and three crustacean hosts in Qingdao, China. For each species, specimens were observed both in vivo and following silver staining. Their SSU rDNA was also sequenced for phylogenetic analyses. Zoothamnium wilberti n. sp. is characterized by the appearance of its colony, which is up to 350 µm high, and usually has fewer than 16 zooids, and the dichotomously branched stalk with transverse wrinkles, the conspicuously conical peristomial disc, and infundibular polykinety 3 comprising three isometric ciliary rows. Baikalonis microdiscus n. sp. can be recognized by its barrel-shaped zooid, small peristomial disc, smooth and short stalk, and its unusual infundibular polykinety 3 comprising a long inner row and a short outer row. Two poorly known species, i.e., Epistylis anastatica and Rhabdostyla commensalis, are redescribed and redefined. Phylogenetic analyses reveal that: (i) R. commensalis is closely related to the family Astylozoidae rather than to the morphologically similar Epistylididae; (ii) B. microdiscus n. sp. is sister to the family Scyphidiidae; (iii) E. anastatica groups with vorticellids and ophrydiids, which further supports the polyphyly of the genus Epistylis; and (iv) Z. wilberti n. sp. is nested within the Zoothamniidae, as expected.


Assuntos
Crustáceos/parasitologia , Oligoimenóforos/classificação , Poliquetos/parasitologia , Animais , China , DNA de Protozoário/genética , Oligoimenóforos/citologia , Oligoimenóforos/genética , Filogenia , Especificidade da Espécie
3.
Parasitol Res ; 118(11): 3129-3137, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31612284

RESUMO

The metacestodes of aploparaksid cestode Wardium cirrosa Krabbe, 1869 parasitic in gulls were found in polychaetes of the family Nereidae collected off the Black Sea coast, Ukraine. Two species of polychaetes, Hediste diversicolor (prevalence 5.3%; intensity 1-3 specimens) and Neanthes succinea (prevalence 9.9%; intensity 1-39 specimens), were infected with cysticercoids that were observed either individually or in accumulations. The preliminary identification of the material based on morphological characteristics was later confirmed by experimental infection of the definitive host, Larus cachinnans (Charadriiformes: Laridae) with metacestodes, and by the identity of the partial 28S rDNA sequences of cysticercoids and experimentally obtained adults. Although previous studies suggested freshwater leeches as the intermediate host for W. cirrosa, our study provides the evidence for marine polychaetes to serve as intermediate hosts. This study is the first to present the morphological characteristics of metacestodes of W. cirrosa in addition to molecular data for this species, as well as reporting the possibility of several cysticercoids developing from a single oncosphere. Morphology of the adult specimens obtained in the experiment was compared with adults of W. cirrosa previously collected from L. cachinnans in Ukraine. The results of our study suggest that further research focused on the elucidation of the life cycles of cestodes within the genus Wardium should consider marine invertebrates as potential intermediate hosts.


Assuntos
Cestoides/fisiologia , Poliquetos/parasitologia , Animais , Cestoides/anatomia & histologia , Cestoides/classificação , DNA de Helmintos , DNA Ribossômico , Feminino , Interações Hospedeiro-Parasita , Estágios do Ciclo de Vida , Masculino , Ucrânia
4.
J Parasitol ; 105(2): 252-262, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30945986

RESUMO

In a survey of marine annelids for myxosporean infection in Charleston Harbor, South Carolina, we collected 3,214 polychaetes from 21 families and found infections in 6 spionid individuals. Based on gross morphology and COI sequencing, all infected spionids were identified as Streblospio benedicti. Infection prevalence was 0.8% (6/734) of that species of spionid, and 0.2% of all 3,214 polychaetes examined. Pansporocysts contained 8 actinospores and developed in the tegument of the annelid host. This is the first myxozoan infection recorded from this polychaete species, second in the family, and the first marine myxozoan found in the Americas. It is the first marine species found to develop in the tegument of its annelid host; a site of development observed only once before, in Ceratonova shasta infections of its freshwater sabellid polychaete host. Mature actinospores were morphologically simple, truncated ellipsoids, lacking processes or ornamentation, 9.0 ± 0.5 µm × 6.0 ± 0.4 µm. Their sack-like shape was similar to 9 of the 12 actinospores described previously from polychaetes; 10/12 had been and ascribed originally to the morphological collective group Tetractinomyxon despite 9 of these having few similarities to the original description of this group. We propose to name the simple, spherical to ellipsoidal spore morphotype Saccimyxon to encompass both our novel actinospore and the 9 other sack-like polychaete actinospore types in the literature. In the present study, 18S rDNA sequencing demonstrated that the myxozoans that infected the 6 spionids were genetically the same species (type sample 1,737 nucleotides, GenBank accession number MH791159) and was not >95% similar to any sequence in GenBank. Phylogenetic analysis showed that the myxozoan species we encountered is basal to the kudoids and thus likely to have a morphologically simple myxospore stage with fewer than 4 valves. However, without a genetic match, the presumptive vertebrate host remains unknown.


Assuntos
Myxozoa/classificação , Poliquetos/parasitologia , Animais , DNA Ribossômico/química , Sedimentos Geológicos , Myxozoa/anatomia & histologia , Myxozoa/genética , Filogenia , RNA Ribossômico 18S/genética , South Carolina , Esporos de Protozoários/classificação , Esporos de Protozoários/genética , Esporos de Protozoários/ultraestrutura
5.
Protist ; 169(6): 826-852, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30453272

RESUMO

Archigregarines are a key group for understanding the early evolution of Apicomplexa. Here we report morphological, ultrastructural, and molecular phylogenetic evidence from two archigregarine species: Selenidium pygospionis sp. n. and S. pherusae sp. n. They exhibited typical features of archigregarines. Additionally, an axial row of vacuoles of a presumably nutrient distribution system was revealed in S. pygospionis. Intracellular stages of S. pygospionis found in the host intestinal epithelium may point to the initial intracellular localization in the course of parasite development. Available archigregarine SSU (18S) rDNA sequences formed four major lineages fitting the taxonomical affiliations of their hosts, but not the morphological or biological features used for the taxonomical revision by Levine (1971). Consequently, the genus Selenidioides Levine, 1971 should be abolished. The branching order of these lineages was unresolved; topology tests rejected neither para- nor monophyly of archigregarines. We provided phylogenies based on LSU (28S) rDNA and near-complete ribosomal operon (concatenated SSU, 5.8S, LSU rDNAs) sequences including S. pygospionis sequences. Although being preliminary, they nevertheless revealed the monophyly of gregarines previously challenged by many molecular phylogenetic studies. Despite their molecular-phylogenetic heterogeneity, archigregarines exhibit an extremely conservative plesiomorphic structure; their ultrastructural key features appear to be symplesiomorphies rather than synapomorphies.


Assuntos
Apicomplexa/classificação , Apicomplexa/isolamento & purificação , Organismos Aquáticos/classificação , Organismos Aquáticos/isolamento & purificação , Filogenia , Animais , Apicomplexa/genética , Apicomplexa/ultraestrutura , Organismos Aquáticos/genética , Organismos Aquáticos/ultraestrutura , Análise por Conglomerados , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Locomoção , Microscopia , Microscopia Eletrônica , Poliquetos/parasitologia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA
6.
Int J Parasitol ; 48(14): 1097-1106, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30367866

RESUMO

Life cycles of spirorchiids that infect the vascular system of turtles are poorly understood. Few life cycles of these blood flukes have been elucidated and all intermediate hosts reported are gastropods (Mollusca), regardless of whether the definitive host is a freshwater or a marine turtle. During a recent survey of blood fluke larvae in polychaetes on the coast of South Carolina, USA, spirorchiid-like cercariae were found to infect the polychaetes Amphitrite ornata (Terebellidae) and Enoplobranchus sanguineus (Polycirridae). Cercariae were large, furcate, with a ventral acetabulum, but no eyespots were observed. Partial sequences of D1-D2 domains of the large ribosomal subunit, the internal transcribed spacer 2, and the mitochondrial cytochrome oxidase 1 genes allowed the identification of sporocysts and cercariae as belonging to two unidentified Neospirorchis species reported from the green turtle, Chelonia mydas, in Florida: Neospirorchis sp. (Neogen 13) in A. ornata and Neospirorchis sp. (Neogen 14) in E. sanguineus. Phylogenetic analysis suggests that infection of annelids by blood flukes evolved separately in aporocotylids and spirorchiids. Our results support the contention that the Spirorchiidae is not a valid family and suggest that Neospirorchis is a monophyletic clade within the paraphyletic Spirorchiidae. Since specificity of spirorchiids for their intermediate hosts is broader than it was thus far assumed, surveys of annelids in turtle habitats are necessary to further our understanding of the life history of these pathogenic parasites.


Assuntos
Oocistos/isolamento & purificação , Poliquetos/parasitologia , Trematódeos/isolamento & purificação , Tartarugas/parasitologia , Animais , Interações Hospedeiro-Parasita
7.
J Invertebr Pathol ; 159: 49-60, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30367870

RESUMO

Gregarines are a common group of parasites that infect the intestines of marine invertebrates, and particularly polychaetes. Here, we describe for the first time four gregarine species that inhabit the intestines of three spionid species: Dipolydora cf. flava, Spio quadrisetosa and Boccardia proboscidea from the Patagonian coast, Argentina, using light and scanning electron microscopy and molecular phylogenetic analyses of small subunit (SSU) rDNA sequences. Even though the spionid species thrive in the same environments, our results showed a high host specificity of the gregarine species. Selenidium cf. axiferens and Polyrhabdina aff. polydorae were both identified from the intestine of D. cf. flava. The new species, Polyrhabdina madrynense sp. n. and Selenidium patagonica sp. n., were described from the intestines of S. quadrisetosa and the invasive species B. proboscidea, respectively. All specimens of D. cf. flava and S. quadrisetosa were infected by gregarines (P = 100%), recording the highest mean intensity values of infection (MI = 80; 60 respectively), in contrast to B. proboscidea (P = 60%; MI = 38). We associated this finding with the recent invasion of this host. It is expected that in the future, an increase of its population density might favour a rising intensity of this gregarine infection.


Assuntos
Apicomplexa/genética , Interações Hospedeiro-Parasita/fisiologia , Poliquetos/parasitologia , Animais , Apicomplexa/classificação , Oceano Atlântico , DNA de Protozoário/genética , Filogenia , Prevalência
8.
Genome Biol Evol ; 10(10): 2736-2748, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30239727

RESUMO

Metchnikovellids are highly specialized hyperparasites, which infect and reproduce inside gregarines (Apicomplexa) inhabiting marine invertebrates. Their phylogenetic affiliation was under constant discussion until recently, when analysis of the first near-complete metchnikovellid genome, that of Amphiamblys sp., placed it in a basal position with respect to most Microsporidia. Microsporidia are a highly diversified lineage of extremely reduced parasites related to Rozellida (Rozellosporidia = Rozellomycota = Cryptomycota) within the Holomycota clade of Opisthokonta. By sequencing DNA from a single-isolated infected gregarine cell we obtained an almost complete genome of a second metchnikovellid species, and the first one of a taxonomically described and well-documented species, Metchnikovella incurvata. Our phylogenomic analyses show that, despite being considerably divergent from each other, M. incurvata forms a monophyletic group with Amphiamplys sp., and confirm that metchnikovellids are one of the deep branches of Microsporidia. Comparative genomic analysis demonstrates that, like most Microsporidia, metchnikovellids lack mitochondrial genes involved in energy transduction and are thus incapable of synthesizing their own ATP via mitochondrial oxidative phosphorylation. They also lack the horizontally acquired ATP transporters widespread in most Microsporidia. We hypothesize that a family of mitochondrial carrier proteins evolved to transport ATP from the host into the metchnikovellid cell. We observe the progressive reduction of genes involved in DNA repair pathways along the evolutionary path of Microsporidia, which might explain, at least partly, the extremely high evolutionary rate of the most derived species. Our data also suggest that genome reduction and acquisition of novel genes co-occurred during the adaptation of Microsporidia to their hosts.


Assuntos
Evolução Biológica , Genoma Fúngico , Microsporídios/genética , Animais , Apicomplexa/microbiologia , Poliquetos/parasitologia
9.
Protist ; 169(3): 333-350, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29864699

RESUMO

This study describes a novel species of Haplozoon, H. ezoense n. sp., a dinoflagellate parasite isolated from the intestines of Praxillella pacifica (Polychaeta). Trophonts (feeding stages) of H. ezoense n. sp. were isolated and studied with scanning and transmission electron microscopy, and molecular phylogenetic analyses was performed using 18S rDNA and 28S rDNA. Trophonts had an average length of 120µm, and were linear, forming a single longitudinal row comprising a trophocyte with a stylet, an average of 14 gonocytes (width=10µm), and bulbous cells that we concluded were likely sporocytes. The surface of H. ezoense n. sp. was covered with projections of the amphiesma. Sections viewed under TEM revealed multiple triple membrane-bound organelles reminiscent of relic non-photosynthetic plastids within the gonocytes. Haplozoon ezoense n. sp., H. praxillellae, and H. axiothellae formed a well-supported clade in the 18S rDNA datasets. The sequences of H. ezoense n. sp. differed from H. praxillellae, a species of Haplozoon isolated from the same host species in the Northeast Pacific, at 88/1,748 bases; and 155/1,752 bases from H. axiothellae. Concatenated 18S rDNA and 28S rDNA datasets were unable to resolve the deeper relationships of Haplozoon in the context of dinoflagellates.


Assuntos
Dinoflagelados/classificação , Dinoflagelados/isolamento & purificação , Filogenia , Plastídeos/ultraestrutura , Animais , Análise por Conglomerados , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Dinoflagelados/genética , Dinoflagelados/ultraestrutura , Trato Gastrointestinal/parasitologia , Estudos Longitudinais , Microscopia , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Poliquetos/parasitologia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Análise de Sequência de DNA
10.
J Eukaryot Microbiol ; 65(5): 637-647, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29399925

RESUMO

Marine gregarines are unicellular parasites of invertebrates commonly found infecting the intestine and coelomic spaces of their hosts. Situated at the base of the apicomplexan tree, marine gregarines offer an opportunity to explore the earliest stages of apicomplexan evolution. Classification of marine gregarines is often based on the morphological traits of the conspicuous feeding stages (trophozoites) in combination with host affiliation and molecular phylogenetic data. Morphological characters of other life stages such as the spore are also used to inform taxonomy when such stages can be found. The reconstruction of gregarine evolutionary history is challenging, due to high levels of intraspecific variation of morphological characters combined with relatively few traits that are taxonomically unambiguous. The current study combined morphological data with a phylogenetic analysis of small subunit rDNA sequences to describe and establish a new genus and species (Cuspisella ishikariensis n. gen., n. sp.) of marine gregarine isolated from the intestine of a polynoid host (Lepidonotus helotypus) collected from Hokkaido, Japan. This new species possesses a set of unusual morphological traits including a spiked attachment apparatus and sits on a long branch on the molecular phylogeny. Furthermore, this study establishes a molecular phylogenetic position for Loxomorpha cf. harmothoe, a previously described marine gregarine, and reveals a new group of gregarines that infect polynoid hosts.


Assuntos
Apicomplexa/isolamento & purificação , Poliquetos/parasitologia , Animais , Apicomplexa/classificação , Apicomplexa/genética , Apicomplexa/ultraestrutura , DNA de Protozoário/genética , Intestinos/parasitologia , Japão , Filogenia , Trofozoítos/genética , Trofozoítos/crescimento & desenvolvimento , Trofozoítos/isolamento & purificação , Trofozoítos/ultraestrutura
11.
J Eukaryot Microbiol ; 65(2): 211-219, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28833883

RESUMO

Gregarine apicomplexans are unicellular parasites commonly found in the intestines and coeloms of invertebrate hosts. Traits associated with the conspicuous feeding stage of gregarines, known as the trophozoite, have been used in combination with molecular phylogenetic data for species delimitation and the reconstruction of evolutionary history. Trophozoite morphology alone is often inadequate for inferring phylogenetic relationships and delimiting species due to frequent cases of high intraspecific variation combined with relatively low interspecific variation. The current study combined morphological data with small subunit (SSU) rDNA sequences to describe and establish two novel marine gregarine species isolated from the intestine of a polychaete host Lumbrineris inflata collected in British Columbia (Canada): Paralecudina anankea n. sp. and Lecudina caspera n. sp. The sister species to the host is Lumbrineris japonica, which can be found on the opposite side of the Pacific Ocean (Japan) and contains two different species of gregarine parasites: Paralecudina polymorpha and Lecudina longissima. Molecular phylogenetic analyses placed P. anankea n. sp. as the sister species to P. polymorpha and L. caspera n. sp. as the sister species to L. longissima. This phylogenetic pattern demonstrates a co-evolutionary history whereby speciation of the host (Lumbrineris) corresponds with simultaneous speciation of the two different lineages of intestinal gregarines (Paralecudina and Lecudina).


Assuntos
Apicomplexa/classificação , Apicomplexa/genética , Filogenia , Poliquetos/parasitologia , Animais , Colúmbia Britânica , DNA de Protozoário/genética , DNA Ribossômico/genética , Intestinos/parasitologia , Japão , Microscopia Eletrônica de Transmissão , Análise de Sequência de DNA , Trofozoítos/fisiologia
12.
Parasitol Int ; 67(2): 150-158, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29100926

RESUMO

Aporocotylidae comprises a diverse family of fish blood flukes, with adults found in blood or body cavity of marine, brackish, or freshwater fish. Aporocotylids are unique among the Digenea with many developing in polychaetes. The life cycle has been elucidated for only a few species that develop in polychaetes from marine/brackish environments and none for western Atlantic aporocotylids. The basis for this study was observations of blood fluke larvae in annelids from South Carolina, USA in 1982 prior to possible usage of molecular tools to specifically identify parasite larvae. Recent description of aporocotylid species and genotyping tools prompted revisiting original collection sites to examine polychaetes and fish as potential hosts. Polycirrid Enoplobranchus sanguineus and terebellids Amphitrite ornata, and Terebella lapidaria revealed infections with aporocotylid larvae. Adult blood flukes were also collected from fish commonly encountered in the same habitat: spotted seatrout (Cynoscion nebulosus), red drum (Sciaenops ocellatus), black drum (Pogonias cromis), and Atlantic croaker (Micropogonias undulatus). Sporocysts containing cercariae were found in individuals of each annelid species. Adult Cardicola parvus were found in spotted seatrout and Atlantic croaker, C. laruei in spotted seatrout, C. currani in red drum, and C. palmeri in black drum. Genotype analysis of ITS-2 and lsrDNA of all forms confirmed conspecific infections by C. parvus in E. sanguineus and A. ornata and C. laruei in T. lapidaria. This is the first description of complete life cycles of aporocotylids in the Western Atlantic and first evidence of cryptic infections of Cy. nebulosus with C. parvus.


Assuntos
Poliquetos/parasitologia , Trematódeos/fisiologia , Infecções por Trematódeos/parasitologia , Truta/parasitologia , Animais , Oceano Atlântico , Cercárias/isolamento & purificação , Genótipo , Estágios do Ciclo de Vida/fisiologia , Oocistos/isolamento & purificação , Perciformes/parasitologia , Trematódeos/genética
13.
Int J Parasitol ; 47(13): 885-891, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28807668

RESUMO

Blood flukes (Aporocotylidae) of actinopterygians (bony fishes) have been shown to infect freshwater gastropods and marine polychaetes as intermediate hosts. However, no life cycle is known for any aporocotylid of chondrichthyans (cartilaginous fishes) and no adult aporocotylid has been linked to a cercaria infecting a bivalve. Here we report two novel infections that fill these gaps. Cercariae consistent with the family Aporocotylidae were found developing in sporocysts in the gonad of the surf pipi, Donax deltoides Lamarck, 1818 (Bivalvia: Donacidae), from Stockton Beach, central New South Wales, Australia. Adult aporocotylids were found in the heart of the giant shovelnose ray, Glaucostegus typus (Anonymous [Bennett], 1830), from Moreton Bay, southeastern Queensland, Australia. Phylogenetic analyses of the 28S rDNA region generated from the new specimens resulted in phylograms in which the two parasites form a strongly supported clade with Chimaerohemecus trondheimensis van der Land, 1967, the only aporocotylid known from a holocephalan and the only other chondrichthyan-infecting aporocotylid for which sequence data are available. Most marine aporocotylids of actinopterygians also form a strongly supported clade. These findings lead us to hypothesise that the aporocotylids of chondrichthyans are distinct from all other blood flukes in infecting bivalves as intermediate hosts. Putative cophyly between three major blood fluke clades and both definitive and intermediate host groups is consistent with diversification of the Schistosomatoidea over 400million years ago.


Assuntos
Bivalves/parasitologia , Doenças dos Peixes/parasitologia , Rajidae/parasitologia , Trematódeos/fisiologia , Infecções por Trematódeos/veterinária , Animais , Sequência de Bases , Teorema de Bayes , Análise por Conglomerados , DNA Ribossômico/análise , DNA Ribossômico/química , Doenças dos Peixes/transmissão , Funções Verossimilhança , Microscopia Eletrônica de Varredura , New South Wales , Filogenia , Poliquetos/parasitologia , Queensland , RNA Ribossômico 28S/genética , Alinhamento de Sequência , Trematódeos/anatomia & histologia , Trematódeos/classificação , Trematódeos/genética , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/transmissão
14.
Eur J Protistol ; 61(Pt A): 265-277, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28778555

RESUMO

Microscopic and phylogenetic analyses were performed on endocommensal astome ciliates retrieved from the middle intestine of a marine cirratulid polychaete, Cirriformia tentaculata, collected in the bay of Roscoff (English Channel, Northwest French coast) and on the Southwest English coast. Three morphotypes of the astome genus Durchoniella were identified, two corresponding to described species (the type species Durchoniella brasili (Léger and Duboscq, 1904) De Puytorac, 1954 and Durchoniella legeriduboscqui De Puytorac, 1954) while a third morphotype remains undescribed. Their small subunit (SSU) rRNA gene sequences showed at least 97.2% identity and phylogenetic analyses grouped them at the base of the subclass Scuticociliatia (Oligohymenophorea), as a sister lineage to all astomes from terrestrial oligochaete annelids. Ultrastructural examination by transmission electron microscopy and fluorescence in situ hybridization analyses revealed the presence of endocytoplasmic cocci and rod-shaped bacteria surrounded by a very thin membrane. These endocytoplasmic bacteria may play a role in the association between endocommensal astome ciliates and cirratulid polychaetes inhabiting in anoxic coastal sediments.


Assuntos
Oligoimenóforos/classificação , Oligoimenóforos/fisiologia , Filogenia , Poliquetos/parasitologia , Animais , Microscopia Eletrônica de Transmissão , Oligoimenóforos/genética , Oligoimenóforos/ultraestrutura , RNA Ribossômico 18S/genética
15.
J Parasitol ; 103(5): 541-546, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28639504

RESUMO

Fish blood flukes of the genus Cardicola (Digenea: Aporocotylidae) are important pathogens in tuna aquaculture. Recent advances in marine blood fluke research have led to the elucidation of the lifecycles of 3 Cardicola spp. infecting tuna; all 3 flukes utilize terebellid polychaetes as the intermediate host. In our survey, we obtained large numbers of Nicolea gracilibranchis infected by larval Cardicola orientalis at our tuna farming site. To determine the spatial and temporal changes in the distribution of N. gracilibranchis surrounding tuna culture cages and their infection by C. orientalis, we conducted monthly sampling for a period of 1 yr. Terebellids were most abundant on the floats and ropes of culture cages, but a significantly higher proportion of infected N. gracilibranchis was detected on ropes, particularly up to 4 m in depth. Cardicola orientalis infection in N. gracilibranchis was clearly seasonal, with a higher infection rate between April and July. Our findings indicate that the infected terebellids inhabit specific microhabitats, and both abiotic and biotic factors likely influence blood fluke infection in the intermediate terebellid host. This information is important to better understand the general biology of marine aporocotylids and may be useful to develop a control strategy for blood fluke infection in tuna aquaculture.


Assuntos
Doenças dos Peixes/parasitologia , Poliquetos/parasitologia , Trematódeos/fisiologia , Infecções por Trematódeos/veterinária , Atum/parasitologia , Animais , Vetores de Doenças , Doenças dos Peixes/transmissão , Pesqueiros , Japão , Distribuição Aleatória , Estações do Ano , Temperatura , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/transmissão , Água/química , Água/parasitologia
16.
Parasitol Int ; 66(1): 972-977, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27835838

RESUMO

Farming of Pacific bluefin tuna (PBT), Thunnus orientalis, is a rapidly growing industry in Japan. Aporocotylid blood flukes of the genus Cardicola comprising C. orientalis, C. opisthorchis and C. forsteri are parasites of economic importance for PBT farming. Recently, terebellid polychaetes have been identified as the intermediate hosts for all these parasites. We collected infected polychaetes, Terebella sp., the intermediate host of C. opisthorchis, from ropes and floats attached to tuna cages in Tsushima, Nagasaki Prefecture, Japan. Also, Neoamphitrite vigintipes (formerly as Amphitrite sp. sensu Shirakashi et al., 2016), the intermediate host of C. forsteri, were collected from culture cages in Kushimoto, Wakayama Prefecture, Japan. The terebellid intermediate hosts harbored the sporocysts and cercariae in their body cavity. Developmental stages of these blood flukes were molecularly identified using species specific PCR primers. In this paper, we describe the cercaria and sporocyst stages of C. opisthorchis and C. forsteri and compare their morphological characteristics among three Cardicola blood flukes infecting PBT. We also discuss phylogenetic relations of the six genera of the terebellid intermediate hosts (Artacama, Lanassa, Longicarpus, Terebella, Nicolea and Neoamphitrite) of blood flukes infecting marine fishes, based on their morphological characters.


Assuntos
Poliquetos/parasitologia , Trematódeos/anatomia & histologia , Trematódeos/genética , Animais , Cercárias/isolamento & purificação , Cercárias/ultraestrutura , Primers do DNA , DNA Espaçador Ribossômico , Doenças dos Peixes/parasitologia , Pesqueiros , Interações Hospedeiro-Parasita , Japão , Estágios do Ciclo de Vida , Microscopia , Oocistos/crescimento & desenvolvimento , Oocistos/ultraestrutura , Filogenia , Reação em Cadeia da Polimerase , Trematódeos/crescimento & desenvolvimento , Trematódeos/isolamento & purificação , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/veterinária , Atum/parasitologia
17.
Parasitol Int ; 66(1): 839-842, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27693561

RESUMO

Cardicola opisthorchis is a blood fluke pathogen significantly affecting cultured Pacific bluefin tuna Thunnus orientalis in Japan. It is known that the intermediate host of C. opisthorchis is a terebellid polychaete Terebella sp. In order to study the intrapolychaete larval development of C. opisthorchis, we transplanted sporocysts, which contained a large number of cercariae, of C. opisthorchis obtained from Terebella sp. into sporocyst-free Terebella sp., which had been maintained at 20°C. The transplanted sporocysts switched from cercarial to sporocystal production by 17days after transplantation (d.a.t.) and daughter sporocysts were released into the polychaete body cavity at 25d.a.t. Subsequently, the released daughter sporocysts produced daughter sporocysts again. Thereafter, daughter sporocysts that contained cercariae appeared at 38d.a.t. and gradually increased. At 51d.a.t., 136 sporocysts that had multiplied from the original two transplanted sporocysts were observed in the body of one polychaete, and cercariae were released from daughter sporocysts inside the polychaete body cavity. Subsequently the cercariae were found to be released outside the polychaete at 57d.a.t. This is the first successful case of in situ observation of the development of a blood fluke within the intermediate host.


Assuntos
Estágios do Ciclo de Vida , Oocistos/crescimento & desenvolvimento , Poliquetos/parasitologia , Trematódeos/crescimento & desenvolvimento , Animais , Cercárias/crescimento & desenvolvimento , Doenças dos Peixes/parasitologia , Pesqueiros , Interações Hospedeiro-Parasita , Japão , Infecções por Trematódeos/parasitologia , Atum/parasitologia
18.
Zootaxa ; 4174(1): 355-385, 2016 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-27811805

RESUMO

The type material of four monotypic genera, Leaniricola, Oestrella, Praxillinicola and Trophoniphila (Copepoda, Cyclopoida), described by M'Intosh (1885) from deep water polychaete hosts collected during the H.M.S. Challenger expedition, is re-examined. Leaniricola rotundata M'Intosh (1885) is removed from its floating status as species inquirenda in the Nereicolidae and fixed as the type of a new family, Leaniricolidae fam. nov., based on the presence of an oral cone and massive, three-dimensionally expanded, mandibular gnathobases which are used to anchor the parasite in the parapodial integument of its host. The ectoparasitic Praxillinicola kroyeri (M'Intosh, 1885), previously treated as a species inquirenda in the Clausiidae, cannot be placed in any of the currently recognized poecilostome families and is here fixed as the type of a new family, Praxillinicolidae fam. nov. Females are characterized by unique bilobate antennules, contained within anterior sockets shared with the reduced antennae, and by paired labral hooks, both of which probably serve as auxiliary attachment organs. Despite its highly transformed body P. kroyeri has retained the plesiomorphic condition of the female genital system, with the gonopores positioned dorsolaterally and the paired copulatory pores lying close together on the midventral surface. The position of the mesoparasitic Trophoniphila bradyi M'Intosh, 1885 in the Bradophilidae is confirmed based on the presence of a median copulatory pore in the female, the disproportionately large egg sacs, the shape of the ectosoma and host utilization. Both sexes of Bradophila pygmaea Levinsen, 1878 are re-examined and the male is redescribed in detail. Flabellicola Gravier, 1918a is treated as a genus incertae sedis in the Bradophilidae. The anal prominence, previously reported in the female of Oestrella (= Melinnacheres) levinseni M'Intosh, 1885 (Saccopsidae), proved upon re-examination to be one of the paired genital apertures. The third and fourth pairs of appendages reported in male saccopsids are here interpreted as the maxillae and maxillipeds, respectively.


Assuntos
Copépodes/anatomia & histologia , Copépodes/classificação , Poliquetos/parasitologia , Animais , Copépodes/fisiologia , Feminino , Masculino , Oceanos e Mares
19.
J Invertebr Pathol ; 137: 49-53, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27150245

RESUMO

We used PCR to screen pooled individuals of Manayunkia speciosa from western Lake Erie, Michigan, USA for myxosporean parasites. Amplicons from positive PCRs were sequenced and showed a Ceratonova species in an estimated 1.1% (95% CI=0.46%, 1.8%) of M. speciosa individuals. We sequenced 18S, ITS1, 5.8S, ITS2 and most of the 28S rDNA regions of this Ceratonova sp., and part of the protein-coding EF2 gene. Phylogenetic analyses of ribosomal and EF2 sequences showed the Lake Erie Ceratonova sp. is most similar to, but genetically distinct from, Ceratonova shasta. Marked interspecific polymorphism in all genes examined, including the ITS barcoding genes, along with geographic location suggests this is an undescribed Ceratonova species. COI sequences showed M. speciosa individuals in Michigan and California are the same species. These findings represent a third parasite in the genus Ceratonova potentially hosted by M. speciosa.


Assuntos
Myxozoa/genética , Poliquetos/parasitologia , Animais , Genes de Protozoários/genética , Lagos/parasitologia , Michigan , Doenças Parasitárias em Animais/parasitologia , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
20.
Protist ; 167(3): 279-301, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27239726

RESUMO

Urosporids (Apicomplexa: Urosporidae) are eugregarines that parasitise marine invertebrates, such as annelids, molluscs, nemerteans and echinoderms, inhabiting their coelom and intestine. Urosporids exhibit considerable morphological plasticity, which correlates with their different modes of motility and variations in structure of their cortical zone, according to the localisation within the host. The gregarines Urospora ovalis and U. travisiae from the marine polychaete Travisia forbesii were investigated with an emphasis on their general morphology and phylogenetic position. Solitary ovoid trophozoites and syzygies of U. ovalis were located free in the host coelom and showed metabolic activity, a non-progressive movement with periodic changes of the cell shape. Solitary trophozoites of U. travisiae, attached to the host tissue or free floating in the coelom, were V-shaped. Detached trophozoites demonstrated gliding motility, a progressive movement without observable cell body changes. In both gregarines, the cortex formed numerous epicytic folds, but superfolds appeared exclusively on the surface of U. ovalis during metabolic activity. SSU rDNA sequences obtained from U. ovalis and U. travisiae revealed that they belong to the Lecudinoidea clade; however, they are not affiliated with other coelomic urosporids (Pterospora spp. and Lithocystis spp.), but surprisingly with intestinal lecudinids (Difficilina spp.) parasitising nemerteans.


Assuntos
Apicomplexa/classificação , Apicomplexa/isolamento & purificação , Poliquetos/parasitologia , Animais , Apicomplexa/citologia , Apicomplexa/genética , Análise por Conglomerados , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Locomoção , Microscopia , Filogenia , RNA Ribossômico 18S/genética , Análise de Sequência de DNA
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