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1.
Although coccidia of the genus Goussia are common parasites of fish, only 2 species have been described in amphibians: G. hyperolisi from common reed frogs Hyperolius viridiflavus from Kenya and G. neglecta from unspecified European water frogs of the genus Rana from Germany. The genus Goussia is characterized by an oocyst, with a fine oocyst wall, containing 4 dizoic sporocysts that are composed of 2 valves joined by a longitudinal suture and lacking a Stieda body (typical for the genus Eimeria). To date, infections in amphibians were generally considered to be specific to the intestine of aquatic larval stages (tadpoles) of anurans. Herein, we report on: (1) the presence of oocysts of Goussia sp. in an extra-intestinal location (liver) of tadpoles of the agile frog R. dalmatina and (2) the presence of oocysts in the liver of both juvenile and subadult R. dalmatina. These observations represent novel traits for Goussia infections in amphibians; they may explain the vertical transmission of Goussia in tadpoles.  相似文献   

2.
A myxozoan species not matching with any described genus was encountered in a survey of fish parasites of freshwater fishes in New York. The parasite was observed in the kidney tubules of bluegill sunfish Lepomis macrochirus. A new genus is described to accommodate Acauda hoffmani n. gen., n. sp., which exhibits pyriform spores with longitudinal ridges and polar capsules perpendicular to the sutural plane. Spores measure 17.9-21.8 μm long and 6.9-11.0 μm wide, with spore valves each with 11-12 ridges. Two polar capsules measure 9.4-12.5 μm long by 2.9-4.0 μm wide and contain a filament coiled 10-15 times. Phylogenetic analysis places A. hoffmani n. gen., n. sp. as a sister to a Myxobilatus and a Hoferellus species. The clustering of these 3 similar genera in the larger 'freshwater' clade of myxozoans does not support their inclusion in the Sphaerosporidae but instead supports the distinct status of the Myxobilatidae Shulman 1953.  相似文献   

3.
The fast-growing nontuberculous mycobacterial species Mycobacterium chelonae was isolated from six captive South African clawed frogs (Xenopus laevis) with chronic weight loss and nonhealing ulcerative skin lesions. Three of the M. chelonae isolates were evaluated to confirm the species identification using polymerase chain reaction restriction analysis. Disease associated with M. chelonae is reported mainly in people and in fish. To our knowledge, this is the first report of disease associated with M. chelonae in a colony of captive Xenopus sp.  相似文献   

4.
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.  相似文献   

5.
Two new myxosporean species in the gallbladders of frogs have recently spread across eastern Australia and cause disease. Cystodiscus axonis sp. n. and Cystodiscus australis sp. n. are species of Myxosporea (Myxozoa) identified from a range of Australian frogs and tadpoles including the introduced Cane toad (Rhinella marina). The new species are defined by their distinct genetic lineage, myxospore morphology and ultrastructure of the pre-sporogonic development. Spores of both species are produced in the gallbladder. Spores of C. axonis sp. n. possess distinct filiform polar appendages (FPA). The pre-sporogonic development of C. axonis sp. n. is within myelinated axons in the central nervous system of hosts, as well as bile ducts of tadpoles. Pre-sporogonic and sporogonic development of C. australis sp. n. is confined to tadpole bile ducts and myxospores of C. australis sp. n. are devoid of FPA. The genus Cystodiscus Lutz, 1889 introduced for Cystodiscus immersus Lutz, 1889 is emended to accompany myxosporean parasites affecting amphibians previously classified in the genus Myxidium sensu lato. A synopsis of described species within Cystodiscus is provided.  相似文献   

6.
Fieldwork conducted throughout Timor-Leste in September 2004 and July 2009 resulted in a collection or recording of 263 herpetological specimens (100 amphibians, 163 reptiles), comprising at least seven species of frogs and toads, 20 species of lizards, seven species of snakes, two species of turtles, and one species of crocodile. Among the amphibians, the most frequently encountered species were toads (Duttaphrynus melanostictus), rice paddy frogs (genus Fejervarya), and rhacophorid treefrogs (Polypedates cf. leucomystax). All three variants of rice paddy frogs encountered represent undescribed species similar to Fejervarya verruculosa from neighboring Wetar Island. Records of Fejervarya cancrivora and Fejervarya limnocharis for Timor Island are apparently errors based on misidentification. We obtained voucher specimens for a total of 147 lizards and voucher photographs only for four specimens of Varanus timorensis. Aside from geckos frequently associated with human habitations (e.g., Gehyra mutilata, Gekko gecko, Hemidactylus frenatus, Hemidactylus platyurus), we discovered an as yet undescribed species of bent-toed gecko, genus Cyrtodactylus, in the Same valley. Our specimens of Hemidactylus platyurus are the first record of this species from Timor-Leste. Commonly encountered skinks included four-fingered skinks (genus Carlia), wedge skinks (genus Sphenomorphus), and night skinks (genus Eremiascincus). Notable among the 15 snakes collected was the frequency of pitvipers (Cryptelytrops insularis), which amounted to over 25% of all snakes. Our specimen of the wolfsnake Lycodon subcinctus is the first record of this species for Timor-Leste. Based on these findings, it appears that the biodiversity of amphibians and reptiles in this remote corner of Wallacea is much greater than previously thought, particularly with respect to scincid lizards. The detail we provide in the species accounts is designed to allow the use of this report as a preliminary field guide to the amphibians and reptiles of Timor-Leste. However, survey work is ongoing.  相似文献   

7.
In this review some important myxosporean species of fish are depicted and described, with special reference to Myxobolus cerebralis (causing whirling disease of salmonids), Sphaerospora renicola (causing Swimbladder inflammation of common carp), Hoferellus carassii (causing kidney enlargement disease of goldfish and proliferative kidney disease [PKD] of salmonids). Detailed information on the life cycles of M. cerebralis, M. cotti, and M. pavlovskii is presented proving that these myxosporeans develop in an intermediate host, the oligochaete worm, Tubifex tubifex to actinosporeans which represent the only infective stage for susceptible fish. These findings imply that the present taxonomy for the phylum Myxozoa has to be revised. Trends for treatment of myxosporean associated diseases are summarized with special emphasis on the antibiotic Fumagillin DCH.  相似文献   

8.
The community of myxosporeans and actinosporeans inhabiting a typical Scottish highland stream and the outflow area of an adjacent salmon hatchery was analysed on the basis of their 18S rDNA sequences. Nine myxosporeans belonging to the genera Sphaerospora, Chloromyxum, Zschokkella, Myxidium, Hoferellus and Myxobilatus were identified from mature spores in different organs of the fish species present. Twelve actinosporean types belonging to the collective groups of neoactinomyxum, aurantiactinomyxon, raabeia, echinactinomyxon and synactinomyxon were found to be released from oligochaete worms collected from sediments. Twenty of the 21 sequences obtained from these myxozoans are new entries to the myxozoan database, and the genera Chloromyxum, Hoferellus and Myxobilatus were entered for the first time. Study of the molecular relationships between the different taxa and with other myxozoan sequences available showed that the myxosporeans inhabiting the urinary system clearly cluster together, independently of host species or spore morphology. However, the sequences of the two Sphaerospora species encountered show considerable differences from other members of this group and all other freshwater myxosporeans, and they were found to occupy an ancestral marine position. Three actinosporeans, i.e. Neoactinomyxum eiseniellae, Aurantiactinomyxon pavinsis and Raabeia 'type 3' were found to represent alternate life cycle stages of Chloromyxum sp., Chloromyxum truttae and Myxidium truttae, respectively (approximately 1400 identical base pairs each). Three other actinosporeans encountered (two echinactinomyxon and one raabeia type) showed over 92% sequence identity with myxosporeans from GenBank, whereas all other actinosporeans formed a closely related group devoid of any known myxosporeans.  相似文献   

9.
Lake Tanganyika harbours the most diverse endemic cichlid fish assemblage of Africa, but its monogenean fish parasites have not been investigated. Here we report, for the first time, on the Gyrodactylus parasites in this hotspot of fish biodiversity. Haptor morphometrics and nuclear ribosomal DNA sequences revealed 3 new species on Zambian Simochromis diagramma: Gyrodactylus sturmbaueri n. sp., G. thysi n. sp. and G. zimbae n. sp. Their distinct morphology and strong genetic differentiation suggest that they belong to distant lineages within the genus Gyrodactylus, and phylogenetic reconstructions suggest affinities with other genera of gyrodactylids. Additional U-shaped haptoral plates in G. thysi n. sp. and a second large spine-like structure in the male copulatory organ of G. zimbae seem to represent new features for the genus. Such large diversity on a single host species can probably be explained by host-switching events during the course of evolution, in agreement with the generally accepted concept that ecological transfer is an important aspect of gyrodactylid speciation. Additional parasitological surveys on other host species, covering a broader phylogenetic and geographical range, should clarify the evolutionary history of Gyrodactylidae on cichlids in the African Great Lake and other parts of Africa.  相似文献   

10.
Ochronconis sp. infection was found in masu salmon (Oncorhynchus masou) with visceral mycosis in Japan. The external and internal clinical signs were reddening of the anal area, swelling of the abdomen due to accumulation of ascitic fluid in the abdominal cavity and extensive swelling of the posterior kidney. Many pale brown, septate hyphae were found in the kidney by direct microscopical examination; these were usually not found in the other organs of infected fish. Histopathological examination of the kidney revealed large granulomas with the fungal hyphae and giant cells. The isolated fungus was identified as a species of the genus Ochroconis and was compared with O. tshawytschae, a known fish pathogen. Based on morphological and growth characteristics, we believe that these cases resulted from infection with a different species.  相似文献   

11.
Polystoma marmorati n. sp. is described as a new polystomatid species parasitic in the urinary bladder of the painted reed frog Hyperolius marmoratus marmoratus collected in southern Natal, South Africa. Parasite prevalence varied from 14.5 to 47.4% and the mean intensity from 1.0 to 1.1. The hamuli of the new species have a characteristic, partly fragmented appearance, a feature also seen in Polystoma batchvarivi, the only other polystome described from a species of the genus Hyperolius. The similarity between the two species, in spite of their geographical separation, is commented upon.  相似文献   

12.
从12S rRNA基因序列研究中国蛙科24种的进化关系   总被引:24,自引:0,他引:24  
测定了中国蛙科动物24种和蟾蜍科的中华大蟾蜍线粒体12S rRNA基因长约400bp片段的序列。采用邻接法,对其数据的系统发生分析表明24种可分成3个支系:第一个支系包括棘腹蛙、合江棘蛙、棘胸蛙、大头蛙、虎纹蛙、倭蛙、泽陆蛙共7种,其中3种棘蛙组成一个单系;第二个支系由3种湍蛙,即戴云湍蛙、华南湍蛙和武夷湍蛙组成,应属于湍蛙亚科;第三支系包含余下的14种蛙,其中5种林蛙和4种臭蛙分别组成一个单系;2种侧褶蛙先聚合后,再与弹琴水蛙聚合,2种粗上先聚合在一起,再与由林蛙组成的单系群聚合。第三支系首先与第二支系相聚,然后它们与第一支系形成姐妹群,即由蛙亚科的7个物种组成的第一支系,不与蛙亚科另14个物种组成的第三支系直接聚合,表明第一支系的物种可能不属于蛙亚科。此外,分子证据提示把陆蛙属、大头蛙属、虎纹蛙属、棘棘属、臭蛙属、粗皮蛙属和侧褶蛙属从原来的蛙属分出有其合理性。、  相似文献   

13.
《Comptes Rendus Palevol》2003,2(5):299-306
A new genus and new species of an ichthyodectiform fish, a new species of the pachyrizodontid Goulmimichthys, as well as specimens of Araripichthys sp. are described from the Agua Nueva Formation (Turonian) of Vallecillo, State of Nuevo León, NE Mexico. The ichthyodectiform fish shows a combination of characters from different families, warranting the creation of a new genus and questioning the monophyly of these families. We report herein the first record of Goulmimichthys and Araripichthys in North America. To cite this article: A. Blanco, L. Cavin, C.R. Palevol 2 (2003).  相似文献   

14.
Microbial contamination of cell cultures: a 2 years study.   总被引:3,自引:0,他引:3  
Cell line contamination is a major drawback of main cell banks of the world and it has cost of losing important biological products or valuable research. The causative agents are different chemicals, invertebrates, bacteria, fungi, parasites, viral species and even other cell lines. In this retrospective study, cell lines from various species such as human, fish, insect, animals either offered or accessed through usual official accession in CGBRI were studied during 2 years (2002-2004) to detect their microbial contaminations and the causative organisms. Samples were taken for sterility test upon cell lines receipt and upon each cell line sub-culture. Samples were examined for bacterial (including mycoplasmas) and fungal contamination using conventional microbiological techniques. The study excluded parasites, viruses and other contaminating agents. This study revealed 39% of specimens were contaminated. The major contaminating agents were mycoplasmas (19%) followed by mixed infection (8%), fungi (8%) and bacteria (4%). Among various bacterial species (except mycoplasmas) Bacillus sp., Enterococcus sp. and Staphylococcus sp. are main bacterial agents and among various fungi Aspergillus sp. followed by Penicillium sp., Sepedonium sp. and Botrytis sp. were main fungal causative agents of CGBRI cell line contamination. Our study also delineates each cell line contamination rate and its causative agents. This is the first report of cell culture contamination from cell banks of Middle-East countries like Iran.  相似文献   

15.
Twelve captive magnificent tree frogs Litoria splendida and 2 green tree frogs L. caerulea on a property in the Darwin rural area (Northern Territory, Australia) either died or were euthanased after becoming lethargic or developing skin lesions. Samples from both species of frog were submitted for histopathology and virus isolation. An irido-like virus was cultured from tissue samples taken from both species and was characterised using electron microscopy, restriction enzyme digests and nucleic acid amplification and sequencing. The isolates were determined to belong to the genus Ranavirus, were indistinguishable from each other and shared a 98.62% nucleotide similarity and a 97.32% deduced amino acid homology with the Bohle iridovirus over a 1161 bp region of the major capsid gene. This is the first isolation of a ranavirus from amphibians in the Northern Territory and the first report of natural infection in these 2 species of native frog. The virus is tentatively named Mahaffey Road virus (MHRV).  相似文献   

16.
A novel intracellular pathogen morphologically similar to the ehrlichiae has been isolated in cell culture and identified as the cause of an epizootic disease of salmonid fish. Like the ehrlichiae, the salmonid pathogen, designated strain LF-89, replicates within membrane-bound cytoplasmic vacuoles in host cells. This agent is the first with characteristics of this type to be isolated from a fish. Analysis of the LF-89 16S rRNA indicated that, unlike the ehrlichiae, LF-89 is a gamma proteobacterium distantly related to Coxiella burnetii and perhaps Wolbachia persica. A new genus and species (Piscirickettsia salmonis gen. nov., sp. nov.) are proposed for this organism, with ATCC(R) VR 1361 as the type strain.  相似文献   

17.
The life cycle of a new haploporid digenean, Hapladena gymnocephali sp. nov., infecting the bald glassy perchlet Ambassis gymnocephalus from the Chaliyar and Kadalundi rivers of Kozhikode district, Kerala, India, is elucidated. The new species is described in detail, its systematic position discussed and compared with related species, H. acanthuri Siddiqi & Cable, 1960 and H. spinosa Manter & Pritchard, 1961. Hapladena gymnocephali is distinctly different from the two latter species in the shape and size of body, nature of testis, extent of vitelline field and excretory bladder. Hapladena gymnocephali has a typical haploporid, two-host life cycle: the gymnocephalous, bi-ocellate, distome cercariae released by the snail Gabbia travancorica are ingested by the fish and develop directly into adults without undergoing a metacercarial stage of development. This is the first report of the genus Hapladena from India, and also the first report of the life cycle of the genus.  相似文献   

18.
Living vertebrates vary drastically in body size, yet few taxa reach the extremely minute size of some frogs and teleost fish. Here we describe two new species of diminutive terrestrial frogs from the megadiverse hotspot island of New Guinea, one of which represents the smallest known vertebrate species, attaining an average body size of only 7.7 mm. Both new species are members of the recently described genus Paedophryne, the four species of which are all among the ten smallest known frog species, making Paedophryne the most diminutive genus of anurans. This discovery highlights intriguing ecological similarities among the numerous independent origins of diminutive anurans, suggesting that minute frogs are not mere oddities, but represent a previously unrecognized ecological guild.  相似文献   

19.
This report provides a detailed ultrastructural study of the life cycle, including proliferative and sporogonic developmental stages, of the first Pleistophora species (microsporidium) obtained from an immune-incompetent patient. In 1985, the organism obtained from a muscle biopsy was initially identified as belonging to the genus Pleistophora, based on spore morphology and its location in a sporophorous vesicle. Since that initial report, at least two new microsporidial genera, Trachipleistophora and Brachiola, have been reported to infect the muscle tissue of immunologically compromised patients. Because Trachipleistophora development is similar to Pleistophora, and as Pleistophora was only known to occur in cold-blooded hosts, the question of the proper classification of this microsporidium arose. The information acquired in this study makes it possible to compare Pleistophora sp. (Ledford et al. 1985) to the known human infections and properly determine its correct taxonomic position. Our ultrastructural data have revealed the formation of multinucleate sporogonial plasmodia, a developmental characteristic of the genus Pleistophora and not Trachipleistophora. A comparison with other species of the genus supports the establishment of a new species. This parasite is given the name Pleistophora ronneafiei n. sp.  相似文献   

20.
在云南省新平县(24°N,101°32’E)采集的华西雨蛙Hyla a.annectans膀胱内检获多盘虫属1新种,新平多盘虫Polystoma xinpingensis sp.nov.。124只华西雨蛙中18只华西雨蛙感染,自然感染率为14.5%。新种与多盘虫属记录种最显著的区别在于:虫体体型小,其体长仅为2967μm。内侧肠管于虫体后1/3处仅形成2条横跨虫体的联合肠管,其它记录种肠管分支多数或形成较复杂的网状。睾丸巨大,呈滤泡状,分散分布直达虫体中部。新种的正、副模式标本保存在云南师范大学生命科学学院。  相似文献   

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