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1.
Syst Parasitol ; 97(5): 491-500, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32737666

RESUMO

Prior to the present study, species of the trematode family Monorchiidae Odhner, 1911 had been reported from four of the ten families of tetraodontiform fishes: the Balistidae, Monacanthidae, Ostraciidae and Tetraodontidae. Here we report the first monorchiid from the family Triacanthidae, Pseudohurleytrema yolandae n. sp. infecting Tripodichthys angustifrons (Hollard), from Moreton Bay, Queensland, Australia. The species conforms well to the morphological concept of the subfamily Hurleytrematinae Yamaguti, 1958, and the genus Pseudohurleytrema Yamaguti, 1954, in the possession of filamented eggs, a bipartite terminal organ, and a unipartite seminal vesicle. Relative to the other three recognised species of Pseudohurleytrema, the present species is distinctive in the size of the testis and eggs, position of the ovary, and the form of the vitellarium and excretory vesicle. We consider Pseudohurleytrema magnum Kaikabad & Bilqees in Bilqees, 1991 as a species inquirenda. Sequence data for the 28S ribosomal RNA gene and cox1 mitochondrial gene were generated for P. yolandae, providing the first molecular data for the genus. Phylogenetic analysis showed that P. yolandae does not form a clade with the other three hurleytrematine genera for which there are molecular data (Helicometroides Yamaguti, 1934, Hurleytrematoides Yamaguti, 1953 and Provitellus Dove & Cribb, 1998), forming a poorly-supported clade with Proctotrema addisoni Searle, Cutmore & Cribb, 2014 within the clade of the subfamily Monorchiinae Odhner, 1911. The four hurleytrematine genera resolved as four distinct clades, indicating that the current subfamilial classification requires comprehensive revision.


Assuntos
Tetraodontiformes/parasitologia , Trematódeos/classificação , Animais , Baías , DNA de Helmintos/genética , Filogenia , Queensland , RNA Ribossômico 28S/genética , Especificidade da Espécie , Trematódeos/anatomia & histologia , Trematódeos/genética
2.
Parasitol Res ; 119(10): 3255-3283, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32856113

RESUMO

Seven new species of Urocleidoides from the gills and skin of nine Neotropical fish hosts (Anostomidae, Parodontidae, and Gymnotidae) are described: Urocleidoides digitabulum n. sp. on Leporinus friderici, Leporinus octofasciatus, and Megaleporinus elongatus (Anostomidae); Urocleidoides solarivaginatus n. sp. on L. friderici, L. octofasciatus, and Leporinus striatus (Anostomidae); Urocleidoides falxus n. sp. and Urocleidoides sapucaiensis n. sp. on M. elongatus; Urocleidoides tenuis n. sp. on Apareiodon piracicabae and Apareiodon affinis (Parodontidae); Urocleidoides sinus n. sp. on L. striatus, Schizodon nasutus, and Schizodon intermedius (Anostomidae); and Urocleidoides uncinus n. sp. on Gymnotus sylvius (Gymnotidae). Urocleidoides paradoxus was also found in this study on L. friderici and included in the phylogenetic analysis. Molecular data (partial 28S rDNA and mitochondrial cytochrome oxidase subunit I) were obtained for U. digitabulum n. sp., U. tenuis n. sp., U. sinus n. sp., and U. uncinus n. sp. The identification of Urocleidoides is amended herein to include all taxonomic modifications observed in this genus over time and add new characteristics observed in the species in the present study. Phylogenetic analysis revealed Urocleidoides digitabulum n. sp. and Urocleidoides sinus n. sp. (parasites of anostomids) closely related in the tree topologies. Furthermore, the new species described herein parasitized phylogenetically distant host species (Characiformes and Gymnotiformes), suggesting the effect of the dynamic process of ecological fitting.


Assuntos
Caraciformes/parasitologia , Gimnotiformes/parasitologia , Platelmintos/isolamento & purificação , Animais , Brasil , DNA Mitocondrial/genética , DNA Ribossômico/genética , Peixes , Brânquias/parasitologia , Especificidade de Hospedeiro , Filogenia , Platelmintos/classificação , Platelmintos/genética , RNA Ribossômico 28S/genética
3.
BMC Infect Dis ; 20(1): 614, 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32811466

RESUMO

BACKGROUND: The most common aetiological agents of mucormycosis are Rhizopus, Mucor, Apophysomyces and Lichtheimia. Apophysomyces is comparatively rare, as it has been reported in less than 3% of mucormycosis cases. The genus Apophysomyces includes six species, and only A. elegans, A. mexicanus, A. variabilis and A. ossiformis have been reported to cause infections in both immunocompetent and immunocompromised patients. CASE PRESENTATION: We present a case of a 46-year-old male patient with bilateral blepharoedema, corneal opacity in the left eye and poorly controlled diabetes mellitus. The patient was subjected to total maxillectomy, exenteration of the left orbit and treatment with liposomal amphotericin B. Direct mycological analysis with KOH 10% revealed hyaline, coenocytic, long and wide hyphae. Apophysomyces ossiformis was identified from maxillary biopsy using 18S-ITS1-5.8S-ITS2-28S rRNA gene amplification and sequencing. The patient requested to be transferred to another hospital to continue treatment, where he died on the ninth day after admittance. CONCLUSION: To the best of our knowledge, this is the first case of rhino-orbital mucormycosis due to A. ossiformis with a fatal outcome. This case reveals the need to identify the fungus causing mucormycosis with molecular methods to identify adequate treatment therapies for patients with this infection.


Assuntos
Complicações do Diabetes/microbiologia , Mucorales/genética , Mucormicose/complicações , Doenças Orbitárias/complicações , Rinite/complicações , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Biópsia , Complicações do Diabetes/tratamento farmacológico , Complicações do Diabetes/cirurgia , Evolução Fatal , Humanos , Hospedeiro Imunocomprometido , Masculino , Maxila/microbiologia , Maxila/patologia , Maxila/cirurgia , Pessoa de Meia-Idade , Mucormicose/tratamento farmacológico , Mucormicose/microbiologia , Mucormicose/cirurgia , Doenças Orbitárias/tratamento farmacológico , Doenças Orbitárias/microbiologia , Doenças Orbitárias/cirurgia , RNA Ribossômico 28S/genética , Rinite/tratamento farmacológico , Rinite/microbiologia , Rinite/cirurgia
4.
Parasitol Res ; 119(11): 3729-3737, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32779020

RESUMO

A new Eimeria species is described from a common bronzewing pigeon (Phaps chalcoptera) (Latham, 1790) in Western Australia. Sporulated oocysts of Eimeria chalcoptereae n. sp. (n = 30) are subspheroidal, 22-25 × 21-24 (23.5 × 22.6) µm; length/width (L/W) ratio 1.0-1.1 (1.04) µm. Wall bi-layered, 1.0-1.4 (1.2) µm thick, outer layer smooth, c.2/3 of total thickness. Micropyle barely discernible. Oocyst residuum is absent, but 2 to 3 small polar granules are present. Sporocysts (n = 30) ellipsoidal, 13-14 × 7-8 (13.5 × 7.2) µm; L/W ratio 1.8-2.0 (1.88). Stieda body present, flattened to half-moon-shaped, 0.5 × 2.0 µm; sub-Stieda present, rounded to trapezoidal, 1.5 × 2.5 µm; para-Stieda body absent; sporocyst residuum present, usually as an irregular body consisting of numerous small granules that appear to be membrane-bound. Sporozoites vermiform, with a robust refractile body and centrally located nucleus. Isolated Eimeria oocysts were analysed at the 18S and 28S ribosomal RNA and the mitochondrial cytochrome oxidase (COI) loci. Analyses revealed that Eimeria chalcoptereae n. sp. shared the highest number of molecular features with an Eimeria sp. previously identified from a domestic pigeon in Australia (KT305927-29), with similarities at these three loci of 98.53%, 97.32% and 94.93%, respectively. According to morphological and molecular analysis, the isolated coccidian parasite is a new species of Eimeria named Eimeria chalcoptereae n. sp. after its host, the common bronzewing pigeon (Phaps chalcoptera) (Columbiformes: Columbidae) (Latham, 1790).


Assuntos
Doenças das Aves/parasitologia , Coccidiose/veterinária , Columbidae/parasitologia , Eimeria/citologia , Eimeria/genética , Animais , Coccidiose/parasitologia , DNA de Protozoário/genética , Eimeria/classificação , Eimeria/crescimento & desenvolvimento , Complexo IV da Cadeia de Transporte de Elétrons/genética , Oocistos/citologia , Filogenia , Proteínas de Protozoários/genética , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Esporozoítos/citologia , Austrália Ocidental
5.
Nucleic Acids Res ; 48(15): 8686-8703, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32710630

RESUMO

H/ACA small nucleolar RNAs (snoRNAs) guide pseudouridylation as part of a small nucleolar ribonucleoprotein complex (snoRNP). Disruption of H/ACA snoRNA levels in stem cells impairs pluripotency, yet it remains unclear how H/ACA snoRNAs contribute to differentiation. To determine if H/ACA snoRNA levels are dynamic during differentiation, we comprehensively profiled H/ACA snoRNA abundance in multiple murine cell types and during differentiation in three cellular models, including mouse embryonic stem cells and mouse myoblasts. We determined that the profiles of H/ACA snoRNA abundance are cell-type specific, and we identified a subset of snoRNAs that are specifically regulated during differentiation. Additionally, we demonstrated that a decrease in Snora27 abundance upon differentiation corresponds to a decrease in pseudouridylation of its target site within the E-site transfer RNA (tRNA) binding region of the 28S ribosomal RNA (rRNA) in the large ribosomal subunit. Together, these data point toward a potential model in which H/ACA snoRNAs are specifically regulated during differentiation to alter pseudouridylation and fine tune ribosome function.


Assuntos
Diferenciação Celular/genética , Células-Tronco Embrionárias Murinas , RNA Nucleolar Pequeno/genética , Ribonucleoproteínas Nucleolares Pequenas/genética , Animais , Sequência de Bases/genética , Camundongos , Mioblastos/metabolismo , Conformação de Ácido Nucleico , Pseudouridina/genética , RNA Ribossômico 28S/genética , Ribossomos/genética
6.
Syst Parasitol ; 97(4): 321-334, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32495189

RESUMO

A new species of deep-sea digenean, Steringophorus merretti n. sp., is described from the bythitid fish Cataetyx laticeps in deep waters of the Goban Spur, Northeastern Atlantic. It is distinguishable from other described members of the genus by its tiny eggs and large cirrus-sac. A phylogenetic tree, based on 28S rDNA sequences, indicates that this species is embedded within a clade of deep-sea species and is sister to the eurybathic species S. thulini Bray & Gibson, 1980. Steringotrema robertpoulini Pérez-Ponce de León, Anglade & Randhawa, 2018 falls within the Steringophorus Odhner, 1905 clade. In view of this the morphological and biological characteristics of species of Steringophorus and Steringotrema are discussed.


Assuntos
Peixes/parasitologia , Trematódeos/classificação , Animais , Oceano Atlântico , Peixes/anatomia & histologia , Peixes/genética , Filogenia , RNA Ribossômico 28S/genética , Especificidade da Espécie
7.
Syst Parasitol ; 97(4): 379-387, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32495190

RESUMO

Adult opecoelid digeneans consistent with Tellervotrema beringi (Mamaev, 1965) were found in the intestine of the deep-water fish Antimora microlepis Bean collected off the northern Kuril Islands (Russia). Earlier, T. beringi was recorded only in macrourid fish. This is the first record of a species of Tellervotrema Gibson & Bray, 1982 from fishes of the family Moridae (Gadiformes). A partial 28S rRNA gene sequence was obtained for this species and was compared with the available sequences on GenBank from other opecoelids. The phylogenetic analysis did not support the current taxonomic hypothesis that the genus Tellervotrema belongs to the subfamily Podocotylinae Dollfus, 1959. Our results demonstrated that species of this genus formed a clade with those of the genera Mesobathylebouria Martin, Huston, Cutmore & Cribb, 2019 and Abyssopedunculus Martin, Huston, Cutmore & Cribb, 2019. The morphological synapomorphies of the Tellervotrema + (Mesobathylebouria + Abyssopedunculus) clade are currently unclear, and this group does not have an adequate subfamilial classification.


Assuntos
Filogenia , Trematódeos/classificação , Trematódeos/genética , Animais , Gadiformes/parasitologia , RNA Ribossômico 28S/genética , Federação Russa , Especificidade da Espécie
8.
Mol Phylogenet Evol ; 150: 106859, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32497831

RESUMO

Parapanteles Ashmead (Braconidae: Microgastrinae) is a medium-sized genus of microgastrine wasps that was erected over a century ago and lacks a unique synapomorphic character, and its monophyly has not been tested by any means. Parapanteles usually are parasitoids of large, unconcealed caterpillars (macrolepidoptera) and have been reared from an unusually large diversity of hosts for a relatively small microgastrine genus. We used Cytochrome Oxidase I sequences ("DNA barcodes") available for Parapanteles and other microgastrines to sample the generic diversity of described and undescribed species currently placed in Parapanteles, and then sequenced four additional genes for this subsample (wingless, elongation factor 1-alpha, ribosomal subunit 28s, and NADH dehydrogenase subunit 1). We constructed individual gene trees and concatenated Bayesian and maximum-likelihood phylogenies for this 5-gene subsample. In these phylogenies, most Parapanteles species formed a monophyletic clade within another genus, Dolichogenidea, while the remaining Parapanteles species were recovered polyphyletically within several other genera. The latter likely represent misidentified members of other morphologically similar genera. Species in the monophyletic clade containing most Parapanteles parasitized caterpillars from only five families - Erebidae (Arctiinae), Geometridae, Saturniidae, Notodontidae, and Crambidae. We do not make any formal taxonomic decisions here because we were not able to include representatives of type species for Parapanteles or other relevant genera, and because we feel such decisions should be reserved until a comprehensive morphological analysis of the boundaries of these genera is accomplished.


Assuntos
Himenópteros/classificação , Animais , Teorema de Bayes , Complexo IV da Cadeia de Transporte de Elétrons/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Himenópteros/genética , Proteínas de Insetos/classificação , Proteínas de Insetos/genética , NADH Desidrogenase/classificação , NADH Desidrogenase/genética , Filogenia , RNA Ribossômico 28S/classificação , RNA Ribossômico 28S/genética
9.
Parasitol Res ; 119(7): 2113-2128, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32476059

RESUMO

Members of the myxosporean genus Kudoa are defined as having a myxospore with four or more shell valves (SVs) and a corresponding number of polar capsules (PCs). Here, we employed integrated taxonomic approaches to four kudoid isolates from Acentrogobius chlorostigmatoides and Konosirus punctatus from the South China Sea, off Guangdong, Pentanemus quinquarius from the Southeast Atlantic Ocean, off West African coast, and Atheresthes stomias from the Bering Sea, off Alaska, and concluded that all these kudoids were novel species, named Kudoa acentrogobia n. sp., Kudoa guangdongensis n. sp., Kudoa iidae n. sp., and Kudoa aburakarei n. sp., respectively. Kudoa guangdongensis n. sp., forming pseudocysts in the trunk muscle myofibers of K. punctatus, had large-sized tripod myxospores with three wing-like SV extensions and three PCs (one prominent PC and two rudimentary PCs). Phylogenetic analyses based on the 18S and 28S ribosomal RNA gene (rDNA) demonstrated its affinity to the genus Kudoa, not to Unicapsula characterized by a myxospore with one prominent PC and two rudimentary PCs, suggesting the atypical nature of this new species in the context of myxospore morphology. Three other kudoid isolates had four SVs and PCs in a semi-quadrated, ray-like, or cruciform myxospore, respectively, forming pseudocysts in the trunk muscle myofibers. Kudoa iidae n. sp. forming pseudocysts in the muscles of P. quinquarius from Southeast Atlantic Ocean had unique myxospores with ray-like form, showing close morphological resemblance to Kudoa rayformis, which were recorded from the muscle of Scomberomorus sierra from the Pacific Ocean off Panama. These two species had a phylogenetic relationship of morphological convergence, evolving separately in different sea areas. It is fairly difficult to differentiate K. acentrogobia n. sp. and K. aburakarei n. sp., prevalent in their host fishes, from kudoid species with similar myxospore morphology (e.g., Kudoa nova and Kudoa thyrsites, respectively), but distinct in phylogeny from known Kudoa spp. Combined taxonomic identification of multivalvulid myxosporeans based on both morphological criteria of isolated myxozoans and their molecular characterization could disclose their real biodiversity and phylogeny.


Assuntos
Myxozoa/classificação , Filogenia , Animais , Oceano Atlântico , China , DNA Ribossômico/genética , Doenças dos Peixes/parasitologia , Peixes/parasitologia , Músculo Esquelético/parasitologia , Myxozoa/citologia , Myxozoa/genética , Oceano Pacífico , RNA Ribossômico 28S/genética
10.
Syst Parasitol ; 97(4): 335-345, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32583335

RESUMO

Enterohaematotrema Mehra, 1940 is emended herein based upon a review of the literature and a description of a new species (Enterohaematotrema triettruongi n. sp.) infecting yellow-headed temple turtles, Heosemys annandalii (Boulenger) (Cryptodira: Geoemydidae), in the Mekong River, Vietnam. The new species differs from the published descriptions of its congeners Enterohaematotrema palaeorticum Mehra, 1940 and Enterohaematotrema hepaticum (Simha, 1958) Simha & Chattopadhyaya, 1980 by having two distinctive oesophageal glands, a short and eversible cirrus (vs protrusive with 3 distinct processes), a dorsal common genital pore that is sinistral (vs ventral and medial), a transverse (vs longitudinal) external seminal vesicle, an oviducal seminal receptacle that is sinistral (vs dextral), and a vitellarium distributing from the caecal bifurcation (anterior to the ventral sucker) to the caecal tips (vs vitellarium not extending anteriad beyond ventral sucker in E. palaeorticum or vitellarium wholly posterior to the terminal genitalia in E. hepaticum). A phylogenetic analysis of the D1-D3 domains of the nuclear large subunit ribosomal DNA (28S) recovered Enterohaematotrema and Platt Roberts & Bullard, 2016 as sister taxa that share a recent common ancestor with the clade comprising Ruavermis Dutton & Bullard, 2020 and Coeuritrema Mehra, 1933. These flukes collectively comprise a monophyletic group of southeast Asian turtle blood flukes. This analysis also indicated that the massive, longitudinal metraterm of species of Enterohaematotrema and Uterotrema Platt & Pichelin, 1994 represents homoplasy (convergent evolution). The present study comprises the first morphological study of original specimens of any species of Enterohematotrema in more than 50 years and is the first molecular phylogenetic placement of the genus among the various turtle blood fluke lineages.


Assuntos
Filogenia , Schistosomatidae/classificação , Tartarugas/parasitologia , Animais , RNA Ribossômico 28S/genética , Rios , Schistosomatidae/anatomia & histologia , Schistosomatidae/genética , Especificidade da Espécie , Vietnã
11.
Syst Parasitol ; 97(4): 403-408, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32562126

RESUMO

Leidynemella shahi n. sp. is described based on material from Panesthia angustipennis cognata Bey-Bienko and Salganea raggei Roth in the Yunnan Province, China. The new species is very similar to L. fusiformis Cobb in Chitwood & Chitwood, 1934, but differs from the latter in the position of the nerve-ring and vulva, and in the length of the eggs. In addition, molecular analysis of partial 28S rDNA sequences also supported the distinct status of the new species.


Assuntos
Baratas/parasitologia , Nematoides/classificação , Animais , China , Nematoides/anatomia & histologia , Nematoides/genética , RNA Ribossômico 28S/genética , Especificidade da Espécie
12.
Int J Syst Evol Microbiol ; 70(5): 3475-3482, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32379017

RESUMO

This study describes a novel fungal species belonging to the genus Gongronella. During a previous work focusing on metalaxyl degradation by Mucorales strains, two isolates from vineyard soil samples collected in the Alentejo region, south Portugal, were identified as a putative novel species based on combined molecular and MALDI-TOF MS data. This new species is described here using a polyphasic approach that combines morphology, internal transcribed spacer of ribosomal DNA (ITS) and 28S ribosomal DNA (LSU) sequence data analysis and proteomic profiling by MALDI-TOF MS. Phenotypic and molecular data enabled this novel species to be clearly distinguished from other Gongronella species with results of combined ITS+LSU analysis showing that the Gongronella species is related to Gongronella butleri and Gongronella brasiliensis. Therefore, from the results of morphological and molecular analyses, isolates MUM 10.262 and MUM 10.263 seem to represent a new Gongronella species and the name Gongronella eborensis sp. nov. is proposed, with the ex-type strain MUM 10.262 (=CCMI 1100=CBS 128763).


Assuntos
Mucorales/classificação , Filogenia , Microbiologia do Solo , DNA Espaçador Ribossômico/genética , Mucorales/isolamento & purificação , Técnicas de Tipagem Micológica , Portugal , Proteômica , RNA Ribossômico 28S/genética , Análise de Sequência de DNA , Vitis
13.
Syst Parasitol ; 97(4): 357-367, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32462534

RESUMO

Ameloblastella martinae n. sp. is described from the gills of the pimelodid catfishes (Siluriformes: Pimelodidae) Sorubim lima (Bloch & Schneider) (type-host) and Hemisorubim platyrhynchos (Valenciennes) in the Peruvian Amazonia, and on Pseudoplatystoma corruscans (Spix & Agassiz) and P. recticulatum Eigenmann & Eigenmann in Argentina. The new species is distinguished from other congeners mainly by the morphology of the male copulatory organ (MCO), which has a form of a corkscrew with tight rings, whereas in other species of Ameloblastella Kritsky, Mendoza-Franco & Scholz, 2000, the MCO is formed by a delicate and coiled tube forming loose rings. Sclerotised structures (haptoral elements and MCO) of specimens of A. martinae n. sp. were used to compare two parasite populations (from Peru and Argentina) using Euclidean distances. Despite the geographical isolation and different host-associations, both populations belong to the same species. The phylogenetic position of A. martinae n. sp. was analysed using partial sequences of the 28S rDNA gene along with 46 species of dactylogyrid parasites of siluriforms (Siluriformes) under Maximum Likelihood (ML) and Bayesian Inference (BI) criteria. Phylogenetic reconstructions showed that Ameloblastella represented by five species, including its type-species A. chavarriai (Price, 1936) from the heptapterid Rhamdia guatemalensis and A. martinae n. sp., was recovered as a well-supported monophyletic group (in both analyses, ML and BI). An additional species, Ameloblastella sp., was found on P. corruscans and P. reticulatum in Argentina. The morphology of the MCO and haptoral elements suggests that Ameloblastella sp. may represent a new species. However, the few specimens found and the lack of genetic sequences of this species precluded its formal description.


Assuntos
Peixes-Gato/parasitologia , Trematódeos/classificação , Animais , Água Doce , Brânquias/parasitologia , Masculino , Filogenia , RNA Ribossômico 28S/genética , América do Sul , Especificidade da Espécie , Trematódeos/anatomia & histologia , Trematódeos/genética
14.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 32(2): 159-167, 2020 Apr 24.
Artigo em Chinês | MEDLINE | ID: mdl-32458605

RESUMO

OBJECTIVE: To characterize a species of the genus Tricula and parasitized trematodes in schistosomiasis-endemic areas of Yunnan Province using a molecular analysis, so as to understand their taxonomic positions. METHODS: Tricula spp. and Oncomelania snails were collected from Xiangyun County, Yunnan Province, and cercaria parasitizing snails were observed using crushing followed by microscopy. Cercaria parasitizing Tricula snails at various morphologies were sampled using a shedding method. Genomic DNA was extracted from snail soft tissues and cercariae, and the 16S rRNA, COI, 28S rDNA genes in snails and the ND1 and 28S rDNA genes in cercariae were amplified using a PCR assay and sequenced. The species of Tricula snails and their parasitized trematodes was characterized using sequence alignment and phylogenetic analysis. RESULTS: Among 382 Tricula snails detected, there were three types of trematode cercariae found, including the non-forked (20.94%, 80/382), double-forked (3.40%, 13/382) and swallow shapes (7.07%, 27/382). Sequence and phylogenetic analyses showed that the 16S rRNA, COI and 28S rDNA gene sequences of this species of Tricula had high homology to those in Delavaya dianchiensis, and were clustered in a branch. Sequencing analysis of the ND1 and 28S rDNA genes revealed that the non-forked cercariae belonged to the family Pleu- rogenidae, the swallow-shaped cercariae belonged to the family Opecoelidae, and the double-forked cercariae belonged to another species of the genus Schistosoma that was different from S. sinensium and S. ovuncatum. CONCLUSIONS: The species and taxonomy of Triculla spp. and their parasitized trematodes are preliminarily determined in schistosomiasis-endemic areas of Yunnan Province; however, further studies are required to investigate the more definite taxonomy and pathogenicity.


Assuntos
Cercárias , Filogenia , Caramujos/classificação , Caramujos/parasitologia , Trematódeos , Animais , Cercárias/genética , Cercárias/isolamento & purificação , China , Complexo IV da Cadeia de Transporte de Elétrons/genética , Doenças Endêmicas , NADH Desidrogenase/genética , RNA Ribossômico 16S/genética , RNA Ribossômico 28S/genética , Esquistossomose/epidemiologia , Esquistossomose/parasitologia , Caramujos/genética , Trematódeos/genética , Trematódeos/isolamento & purificação
15.
J Parasitol ; 106(2): 261-267, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32294757

RESUMO

The genus Rhabdochona Railliet, 1916 is one of the most speciose group of nematodes, parasites of freshwater fishes, with approximately 103 species described worldwide. Twenty-two species have been recorded in the Americas, 14 of them in Mexico. In this paper we describe a new species of Rhabdochona on the basis of light and scanning electron microscopy and molecular tools. Rhabdochona adentata n. sp. was recovered from the gallbladder of the freshwater Oaxaca killifish, Profundulus oaxacae (Meek, 1902) (Profundulidae) captured in the Río Grande, State of Oaxaca, Mexico. Rhabdochona adentata n. sp. differs markedly from its congeners by possessing an unusual prostom lacking anterior teeth, small simple deirids, and the location of the excretory pore at the level of the union of the muscular and glandular esophagus. Sequences of cytochrome c oxidase subunit I (COI) from mitochondrial deoxyribonucleic acid and the D2 + D3 domains of the large ribosomal subunit (28S) were obtained from 3 specimens and were analyzed using maximum likelihood and Bayesian inference analyses. Phylogenetic analyses using COI and 28S genes recovered 1 new lineage of Rhabdochona. The new species is described on the basis of a detailed morphological study. This parasite represents the first species of Rhabdochona without prostomal teeth and with a different site of infection, the gallbladder.


Assuntos
Ciprinodontiformes/parasitologia , Doenças dos Peixes/parasitologia , Infecções por Spirurida/veterinária , Spiruroidea/classificação , Animais , Teorema de Bayes , DNA/química , DNA/isolamento & purificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Doenças dos Peixes/epidemiologia , Água Doce , Vesícula Biliar/parasitologia , Funções Verossimilhança , Masculino , México/epidemiologia , Microscopia Eletrônica de Varredura/veterinária , Filogenia , Prevalência , RNA Ribossômico 28S/genética , Rios , Infecções por Spirurida/epidemiologia , Infecções por Spirurida/parasitologia , Spiruroidea/genética , Spiruroidea/ultraestrutura
16.
BMC Evol Biol ; 20(1): 37, 2020 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-32171235

RESUMO

BACKGROUND: Various ecological groups of earthworms very likely constitute sharply isolated niches that might permit speciation of their symbiotic ciliates, even though no distinct morphological features appear to be recognizable among ciliates originating from different host groups. The nuclear highly variable ITS1-5.8S-ITS2 region and the hypervariable D1/D2 region of the 28S rRNA gene have proven to be useful tools for the delimitation of species boundaries in closely related free-living ciliate taxa. In the present study, the power of these molecular markers as well as of the secondary structure of the ITS2 molecule were tested for the first time in order to discriminate the species of endosymbiotic ciliates that were isolated from the gastrointestinal tract of three ecologically different groups of lumbricid earthworms. RESULTS: Nineteen new ITS1-5.8S-ITS2 region and D1/D2-28S rRNA gene sequences were obtained from five astome species (Anoplophrya lumbrici, A. vulgaris, Metaradiophrya lumbrici, M. varians, and Subanoplophrya nodulata comb. n.), which were living in the digestive tube of three ecological groups of earthworms. Phylogenetic analyses of the rRNA locus and secondary structure analyses of the ITS2 molecule robustly resolved their phylogenetic relationships and supported the distinctness of all five species, although previous multivariate morphometric analyses were not able to separate congeners in the genera Anoplophrya and Metaradiophrya. The occurrence of all five taxa, as delimited by molecular analyses, was perfectly correlated with the ecological groups of their host earthworms. CONCLUSIONS: The present study indicates that morphology-based taxonomy of astome ciliates needs to be tested in the light of molecular and ecological data as well. The use of morphological identification alone is likely to miss species that are well delimited based on molecular markers and ecological traits and can lead to the underestimation of diversity and overestimation of host range. An integrative approach along with distinctly increased taxon sampling would be helpful to assess the consistency of the eco-evolutionary trend in astome ciliates.


Assuntos
Cilióforos/classificação , Cilióforos/isolamento & purificação , DNA Espaçador Ribossômico/genética , Trato Gastrointestinal/parasitologia , Oligoquetos/parasitologia , RNA Ribossômico 28S/genética , Animais , Cilióforos/genética , DNA Espaçador Ribossômico/análise , Ecologia , Genes de RNAr/genética , Interações Hospedeiro-Parasita/fisiologia , Oligoquetos/classificação , Oligoquetos/genética , Filogenia , RNA Ribossômico , RNA Ribossômico 28S/análise , Análise de Sequência de DNA
17.
BMC Evol Biol ; 20(1): 36, 2020 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-32171237

RESUMO

BACKGROUND: The family Aegisthidae is known as typical component of deep-sea hyperbenthic waters that gradually colonized other marine environments. The phylogenetic relationships within this family have been examined here including hyperbenthic, planktonic, benthic forms and two associated Aegisthidae species. RESULTS: Ninety four specimens belong to 14 genera were studied using 18S and 28S rRNA and COI mtDNA. Bayesian analysis supports the monophyly of 10 genera whereas Andromastax, Jamstecia, Nudivorax and Aegisthus revealed to be paraphyletic. The first offshoot of the phylogenetic tree is a clade consists of the undescribed genus Aegisthidae gen.1 sister to the two monophyletic genera Cerviniella and Hase, whereas the other Cerviniinae members (represented by Cervinia and Expansicervinia) assemble a monophylum, sister to the hyperbenthic and planktonic aegisthid genera, resulting in the paraphyly of the subfamily Cerviniinae. Hence, we defined the new subfamily Cerviniellinae subfam. nov. encompassing the three benthic genera Cerviniella, Hase and Eucanuella. The subfamily Cerviniinae has been re-defined to include Cervinia, Expansicervinia and Paracerviniella. Members of the subfamily Pontostratiotinae were clustered into two clades, one consists of the genus Stratiopontotes sister to an undescribed genus + Cerviniopsis and Siphonis. The second contains Pontostratiotes sister to the members of the planktonic subfamily Aegisthinae, resulting in the paraphyly of the Pontostratiotinae. Therefore, the Pontostratiotinae has been re-defined to include only members of the genus Pontostratiotes; whereas the subfamily Cerviniopseinae has been re-erected and re-defined containing Stratiopontotes, Cerviniopsis, Siphonis, Aegisthidae gen. 2, Herdmaniopsis, Hemicervinia and Tonpostratiotes. Within this subfamily, the associated Siphonis clusters as sister to the Cerviniopsis represents an example of convergent evolution in which the possession of a stylet-like mandible and an oral cone reminiscent of the Siphonostomatoida. The planktonic Aegisthus, Andromastax, Jamstecia, Nudivorax and Scabrantenna confirm the monophylom Aegisthinae, sister to the Pontostratiotinae. CONCLUSIONS: Our DNA based phylogeny reveals the deep-sea origin of Aegisthidae by placing benthic Aegisthidae gen.1 and Cerviniellinae subfam. nov. as the most basal lineages. Secondary adaptations to hyperbenthic and planktonic realms, as well as associated lifestyle were discovered here by the derived positions of Pontostratiotinae, Aegisthinae and Siphonis respectively.


Assuntos
Aclimatação/fisiologia , Copépodes/anatomia & histologia , Copépodes/classificação , Ecossistema , Água do Mar , Animais , Copépodes/genética , DNA Mitocondrial/análise , DNA Mitocondrial/genética , Ecótipo , Filogenia , Filogeografia , RNA Ribossômico 28S/análise , RNA Ribossômico 28S/genética , Análise de Sequência de DNA
18.
J Helminthol ; 94: e136, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32138801

RESUMO

Many members of Fasciolidae are common trematodes in cattle, buffaloes, sheep, elephants, pigs, with some capable of infecting humans also. In this study, the complete or near-complete sequences of ribosomal transcription unit (rTU or rDNA), each of Fasciola hepatica (Australia), Fascioloides jacksoni (Sri Lanka), Fasciolopsis buski (Vietnam) and three isolates of F. gigantica (Vietnam), were obtained and characterized. The full length of rDNA for each F. hepatica, 'hybrid' Fasciola sp., Fas. jacksoni and Fa. Buski, was 7657 bp, 7966 bp, 7781 bp and 8361 bp, with the complete intergenic spacer region (IGS) (862 bp, 1170 bp, 987 bp and 561 bp), respectively. The rDNA of two 'pure' F. gigantica isolates from Vietnam was 6794 bp with unsequenced IGS. For 28S rRNA genes the Fasciola spp. are equal, 1958 bp for 18S, 160 bp for 5.8S, 3863 bp and 454 bp for ITS1 but ITS2 differ by one nucleotide (Thymine) (359 or 360 bp). The ITS1 of the sensu lato Fa. buski has some distinguishable features, 286 bp for ITS2, 3862 bp for 28S and four repeat units of 356-361 bp each found in ITS1. The 28S rDNA analysis showed the lowest level of divergence (0-0.57%) between F. hepatica and F. gigantica and higher (2.23-2.62%) and highest (6-6.42%) for Fas. jacksoni and Fasciolopsis, respectively. The tree of 43 strains/species clearly produced a well-supported phylogeny, where 18 fasciolids consistently grouped, forming a discrete Fasciolidae clade, distinct from Philophthalmidae, Echinostomatidae and Echinochasmidae in Echinostomatoidea. Fascioloides jacksoni is outside Fasciola spp.: basal with Fas. magna, as previously demonstrated.


Assuntos
DNA de Helmintos/genética , Fasciolidae/classificação , Fasciolidae/genética , Filogenia , Animais , Bovinos/parasitologia , Doenças dos Bovinos/parasitologia , DNA Ribossômico/genética , DNA Espaçador Ribossômico/genética , Elefantes/parasitologia , Humanos , RNA Ribossômico 28S/genética , Análise de Sequência de DNA
19.
Parasit Vectors ; 13(1): 45, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32020879

RESUMO

BACKGROUND: Microcotyle erythrini van Beneden & Hesse, 1863 (Platyhelminthes: Monogenea) and other closely related species of the genus are often considered as cryptic. Records in hosts other than the type-host with no species confirmation by molecular analyses have contributed to this situation. METHODS: Gill parasites of five sparid fishes, Boops boops (L.), Pagellus erythrinus (L.), P. acarne (Risso), Dentex dentex (L.) and Pagrus pagrus (L.), from the Western Mediterranean off Spain were collected. Specimens of Microcotyle spp. were characterised both molecularly and morphologically. Partial fragments (domains D1-D3) of the 28S rRNA gene and the cytochrome c oxidase subunit 1 (cox1) gene were amplified and used for molecular identification and phylogenetic reconstruction. Principal components analysis was used to look for patterns of morphological separation. RESULTS: Molecular analyses confirmed the identity of three species: M. erythrini ex P. erythrinus and Pa. pagrus; M. isyebi Bouguerche, Gey, Justine & Tazerouti, 2019 ex B. boops; and a species new to science described herein, M. whittingtoni n. sp. ex D. dentex. The specific morphological traits and confirmed hosts (P. erythrinus and Pa. pagrus) are delimited here in order to avoid misidentifications of M. erythrini (sensu stricto). Microcotyle erythrini (s.s.) is mostly differentiated by the shape of its haptor, which is also longer than in the other congeners. New morphological and molecular data are provided for M. isyebi from the Spanish Mediterranean enlarging the data on its geographical range. Microcotyle whittingtoni n. sp. is described from D. dentex and distinguished from the remaining currently recognised species of the genus by the number and robustness of the clamps. CONCLUSIONS: New diagnostic morphological traits useful to differentiate Microcotyle spp. are suggested: (i) haptor dimensions including lobes; (ii) the thickness of the clamps; (iii) the size and shape of spines of the genital atrium; (iv) the extension of the posterior extremities of vitelline fields; and (v) the shape of egg filaments. The use of new morphological approaches may allow considering these species of Microcotyle as being pseudocryptic. The use of representative undamaged specimens that have been genetically confirmed as conspecific is considered crucial to avoid abnormally wide morphological ranges that prevent species differentiation.


Assuntos
Classificação , Perciformes/parasitologia , Trematódeos/anatomia & histologia , Trematódeos/classificação , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Brânquias/parasitologia , Filogenia , RNA Ribossômico 28S/genética , Trematódeos/genética
20.
J Parasitol ; 106(1): 133-156, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32048913

RESUMO

Four new species of Paraorygmatobothrium are described from carcharhinid shark species from the Gulf of Mexico and the U.S. coast of the northwestern Atlantic Ocean. Paraorygmatobothrium bullardi n. sp. is described from Carcharhinus brevipinna as its type host, and from Carcharhinus acronotus and Carcharhinus limbatus. Paraorygmatobothrium campbelli n. sp. is described from Rhizoprionodon terraenovae. Paraorygmatobothrium deburonae n. sp. is described from Carcharhinus isodon as its type host, as well as from C. brevipinna, C. limbatus, and R. terraenovae. Paraorygmatobothrium mattisi n. sp. is described from R. terraenovae as its type host, and from C. brevipinna and C. limbatus. These 4 species differ from other species of Paraorygmatobothrium and from each other in bothridial microthrix shape, and in various combinations of features such as the total length of the worm, apical sucker size, bothridial musculature, proglottid number, testes number, and genital pore position. Difficulty in differentiating these 4 species from one another, and from other species of Paraorygmatobothrium, points to limitations in the use of morphology alone to recognize species diversity in this genus. A phylogenetic analysis of Paraorygmatobothrium and related genera, based on partial (D1-D3) 28S rDNA sequence data, confirms that the genus is not monophyletic. Genetic distances of COI revealed that sequence divergence between species of Paraorygmatobothrium is generally at least an order of magnitude larger than COI divergence within a species. Patterns of host use for 3 of the new species are consistent with previous findings that point to a lack of host specificity in Paraorygmatobothrium.


Assuntos
Cestoides/classificação , Infecções por Cestoides/veterinária , Doenças dos Peixes/parasitologia , Tubarões/parasitologia , Animais , Oceano Atlântico , Cestoides/genética , Cestoides/fisiologia , Cestoides/ultraestrutura , Infecções por Cestoides/parasitologia , DNA Ribossômico/química , Complexo IV da Cadeia de Transporte de Elétrons/genética , Golfo do México , Especificidade de Hospedeiro , Intestinos/parasitologia , Microscopia Eletrônica de Varredura/veterinária , Filogenia , RNA Ribossômico 28S/genética , Tubarões/classificação
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