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1.
Polystoma dawiekoki n. sp. is described as a new species of the Polystomatidae parasitic in the urinary bladder of the plain grass frog Ptychadena anchietae. This parasite was collected at Mkuze town and Mkuze Game Reserve in northern Kwazulu-Natal Province, in the Kruger National Park in Mpumalanga Province, South Africa, and at Bulwa in Tanga Province, East Usambara Mountains, Tanzania. It is distinguished from other African Polystoma species by a combination of characters, including the body size, size and shape of marginal hooklets and the haptor length to body length ratio. The presence of adult, as well as subadult, parasites in the same individuals, as is known for Eupolystoma, represents a significant evolutionary departure from the pattern of transmission typical of Polystoma in most of the other anuran hosts.  相似文献   

2.
Polystoma nacialtuneli n. sp. is described from the urinary bladder of the eastern spadefoot, Pelobates syriacus from Turkey. This is the fifth polystome species known from Turkey and the third species in Pelobates. We show that this new parasite species can be distinguished from other polystome species in the area by a combination of characteristics, including parasite size and the shape and size of the hamuli. Polystoma pelobatis from Pelobates cultripes has a pair of well-developed hamuli, while P. fuscus from Pe. fuscus characteristically has a pair of underdeveloped hamuli barely larger than the marginal hooklets. Polystoma nacialtuneli n. sp. has well-developed hamuli that vary significantly in shape. Phylogenetic relationships of P. nacialtuneli n. sp. within Polystoma, supplemented with molecular divergences estimated from internal transcribed spacer 1 (ITS1) sequences, indicate that they are well separated from their closest relatives, i.e. P. fuscus and P. pelobatis from Pe. fuscus and Pe. cultripes, respectively.  相似文献   

3.
A new species of polystomatid monogenean, Polystoma cuvieri, is described from the urinary bladder of the leptodactylid frog Physalaemus cuvieri Fitzinger in Paraguay. This new species possesses a reticulated intestine and hamuli of about 350 microns long. The closest species is Polystoma napoensis Vaucher, 1987, described from Osteocephalus spp. in Ecuador. The Paraguayan material is distinguished by the blade size of the hamuli. The hamuli blades appear to be useful in Polystoma systematics.  相似文献   

4.
A new genus, Pseudokuhnia, is established for Kuhnia minor, family Mazocraeidae. It differs from Kuhnia in the presence of two dorso-lateral vaginae, supported by surface ridges; differently shaped large genital hooks, large hamuli and ovary; an opisthaptor which is ventral to and well separated from the body proper; and a rudimentary antero-supplementarium of the clamps. The Atlantic population of P. minor differs from the Pacific population mainly in the larger size of the hamuli and the smaller size of the large and small genital hooks.  相似文献   

5.
Microcotyle omanae n. sp. (Monogenea: Microcotylidae) is described from the gills of Cheimerius nufar (Valenciennes) (Sparidae) from the Arabian Sea. The new species closely resembles Microcotyle arripis Sandars, 1945, M. helotes Sandars, 1944, M. caudata Goto, 1984 and M. sebastis Goto, 1984, which have also been found in the Indo-Pacific. Microcotyle omanae n. sp. differs from M. arripis, M. helotes and M. caudata by its greater number of testes, from M. arripis, M. helotes by its greater length of the genital atrium, length/width ratio of the genital atrium and length of the eggs, and from M. helotes also in greater width of the clamps, from M. caudata and M. sebastis in its greater number of clamps and additionally from M. sebastis by its smaller genital atrial spines and clamps and by the ratio between length and width of the genital atrium. Moreover, the mature specimens of the new species have greater average body length than all above mentioned species. Correlations between 15 morphometric characters and body length are analysed in the new species, and their significance for species differentiation is discussed.  相似文献   

6.
Polystoma fuscus n. sp. (Polystomatidae, Polystomatinae) is described from the urinary bladder of Pelobates fuscus (Pelobatidae) in Bulgaria. Its general morphology is similar to that of other members of the genus but distinguished from them by the underdeveloped hamuli similar to the larval hamular primordia. The new species is also differentiated from the members of the genera of the subfamily Polystomatinae described without hamuli.  相似文献   

7.
Polystoma testimagna n. sp. is described as a new species of the Polystomatidae, parasitic in the urinary bladder of the striped stream frog Strongylopus f. fasciatus collected in the Vernon Crookes Nature Reserve, Natal, South Africa. Parasite prevalence was found to be 50.0% and 27.7% in two successive years, and the mean intensity was 1.5 and 1.6, respectively. The species occurs together with another Polystoma species in the same water body and within one kilometre from a third species. Aspects of host specificity are discussed and data on the ecology and distribution of the host presented.  相似文献   

8.
Polystoma macrocnemis n. sp. (Polystomatidae) is described from the urinary bladder of Rana macrocnemis (Ranidae) in Turkey. Its general morphology is similar to that of other members of the genus, but it is distinguished from closely related species by numerical parameters of the hamuli and also by its host species and geographical range.  相似文献   

9.
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   

10.
Considering the addition of intermediate transmission steps during life cycle evolution, developmental plasticity, canalization forces and inherited parental effect must be invoked to explain new host colonization. Unfortunately, there is a lack of experimental procedures and relevant models to explore the adaptive value of alternative developmental phenotypes during life cycle evolution. However, within the monogeneans that are characterized by a direct life cycle, an extension of the transmission strategy of amphibian parasites has been reported within species of Polystoma and Metapolystoma (Polyopisthocotylea; Polystomatidae). In this study, we tested whether the infection success of Polystoma gallieni within tadpoles of its specific host, the Stripeless Tree Frog Hyla meridionalis, differs depending on the parental origin of the oncomiracidium. An increase in the infection success of the parasitic larvae when exposed to the same experimental conditions as their parents was expected as an adaptive pattern of non-genetic inherited information. Twice as many parasites were actually recorded from tadpoles infected with oncomiracidia hatching from eggs of the bladder parental phenotype (1.63 ± 0.82 parasites per host) than from tadpoles infected with oncomiracidia hatching from eggs of the branchial parental phenotype (0.83 ± 0.64 parasites per host). Because in natural environments the alternation of the two phenotypes is likely to occur due to the ecology of its host, the differential infection success within young tadpoles could have an adaptive value that favors the parasite transmission over time.  相似文献   

11.
Acanthocheilonema delicata n. sp. (Filarioidea: Onchocercidae: Onchocercinae) is described based on adult filarioids and microfilariae obtained from subcutaneous connective tissues and skin, respectively, of Japanese badgers (Meles anakuma) in Wakayama Prefecture, Japan. No endemic species of the genus had been found in Japan. Recently, some filarioids (e.g., Acanthocheilonema reconditum, Dirofilaria spp., and Onchocerca spp.) have come to light as causative agents of zoonosis worldwide. The new species was readily distinguished from its congeners by morphologic characteristics such as body length, body width, esophagus length, spicule length, and the length of microfilariae. Based on the molecular data of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene, A. delicata n. sp. was included in the clade of the genus Acanthocheilonema but differed from two other congeneric species available for study, A. viteae and A. reconditum. Acanthocheilonema delicata n. sp. did not harbor Wolbachia. It is likely that the fauna of filarioids from mammals on the Japanese islands is characterized by a high level of endemicity.  相似文献   

12.
Three keys to the species of Neolebouria Gibson, 1976, representing three body types, are provided based on the location of the genital pore relative to the intestinal bifurcation. These are: the lanceolata body type, where the genital pore is clearly prebifurcal; the diacopae body type, where the genital pore is located at or near the level of the intestinal bifurcation; and the maorum body type, where the genital pore is clearly postbifurcal. Fifteen species were assigned to the lanceolata body type; eight species to the diacopae body type; and four species to the maorum body type. Neolebouria truncata (Linton, 1940) is redescribed and N. georgiensis Gibson, 1976 is reinstated as a valid species. Neither N. georgiensis, nor N. antarctica Szidat & Graefe, 1967 (syn. Crassicutis antarcticus Szidat & Graefe, 1967), as described by Zdzitowiecki et al. (1993), represent N. antarctica, as originally described, and N. georgiensis and N. antarctica, as described by Zdzitowiecki et al. (1993), may be conspecific.  相似文献   

13.
Malformations and increased mortality due to infection by the digenetic trematode, Riberioa ondatrae have been reported for many species of amphibians. Severe malformations have also been reported in the Common Hourglass Tree Frog, Polypedates cruciger induced by pleurolophocercous cercariae in Sri Lanka in addition to the changes in the behaviour, development and survival of the host. We exposed pre-limb bud stage tadpoles (Gosner stages 25–26) of the Asian Common Toad, Duttaphrynus melanostictus to the same pleurolophocercous type cercariae under laboratory conditions. Molecular and morphological identification showed that these cercariae belonged Acanthostomum burminis infecting freshwater snakes as definitive hosts. These cercariae induced malformations (27.8%) and reduced survival to metamorphosis (53.8%). The magnitude of the effects increased with the dose of cercariae. Types of malformations were mainly axial, such as scoliosis and kyphosis. Severe limb malformations such as extra or missing limbs as reported for amphibians exposed to R. ondatrae were not observed in the D. melanostictus. Same authors reported a higher percentage of malformations previously when P. cruciger was exposed to the cercariae A. burminis compared to D. melanostictus. However, tadpoles of D. melanostictus, which are smaller compared to those of P. cruciger, experienced higher mortality than P. cruciger tadpoles. Trematode induced malformations and mortality in amphibians are highly variable and depend on multiple factors such as host species differences such as resistance to infection and tolerance, life-history characteristics such as size at metamorphosis and length of the metamorphosis period, and other factors such as size of the amphibian at the time of trematode exposure.  相似文献   

14.
The genus Entomelas Travassos, 1930 currently includes nine species of rhabdiasid nematodes, eight of them parasitic in lizards and only one, Entomelas sylvestris Baker, 1982, parasitic in amphibians. Entomelas sylvestris was originally described from the Forest Rain Frog Breviceps sylvestris FitzSimons in South Africa and was not reported since. It was placed in the genus Entomelas without any specific arguments for this taxonomic decision, presumably mainly based on details of the buccal capsule morphology. We have found this species in the same host in Limpopo province, South Africa. Molecular phylogenetic analysis based on the newly-obtained sequence of complete ITS region and partial nuclear large ribosomal subunit (28S) gene of E. sylvestris and previously published sequences of a variety of other rhabdiasid taxa, has convincingly demonstrated that this species does not belong in Entomelas. Instead, it clustered together with the members of Rhabdias Stiles & Hassall, 1905 from amphibian hosts. Therefore, we transfer E. sylvestris into Rhabdias as Rhabdias sylvestris (Baker, 1982) n. comb. In our analysis E. sylvestris appears, albeit with weak support, as a basal/sister taxon to the rest of Rhabdias spp. which explains to some extent the differences in the buccal capsule morphology between this species and other Rhabdias spp.  相似文献   

15.
Among monogeneans that display direct life cycles, plastic developmental strategies may have been selected to counter the lack of transmission opportunities. Within amphibian polystomatids, some species of the genus Polystoma develop into two different phenotypes depending on the host physiological stage to which free swimming larvae attach. When oncomiracidia infest old tadpoles, they develop slowly and migrate during host metamorphosis towards the bladder where they reach maturity. On the other hand when larvae infest young tadpoles, they develop rapidly into neotenic phenotypes that reproduce in the branchial chamber. These alternative developments are explored through experimental infestations with Polystoma gallieni, the specific polystome of the stripeless tree frog Hyla meridionalis. When oncomiracidia were left for 6 h in water in which young tadpoles had been previously maintained for one day, they mainly developed into the neotenic phenotype regardless of the tadpole stage they encountered later. This indicates that P. gallieni could collect released host-derived signals before physical contact with its host.  相似文献   

16.
The Seto Inland Sea, the largest inland sea in Japan, is a rich fishery with high biodiversity and productivity. Monogeneans have been studied for more than 120 years, and 58 nominal species have been recorded in the Seto inland Sea. This study provided DNA information on five species of Benedenia sensu lato (Capsalidae) from marine fishes from the sea, and one of them, Benedenia kobudai n. sp., is described from Semicossyphus reticulatus (Perciformes: Labridae). This new species differs from the other congeners by the hooded appearance between the anterior attachment organs, the morphology of the penis, the absence of the lobe near the vaginal pore and the common genital pore, the position of the vaginal pore, the germarium lying near the slightly hexagonal testes, the morphology of the haptor, and the shape and position of the hamuli. Phylogenetic analysis showed B. kobudai n. sp. in a separate clade from the other Benedenia species, B. epinepheli, B. hoshinai, B. sekii, and B. seriolae collected from the sea. Each of the newly provided DNA sequences (28S rDNA, ITS1‐5.8S-ITS2, cox1) of the above four species are based on specimens obtained from the type hosts and/or type localities and are considered important for future taxonomic re-examination and confirmation of the reliability of the registered sequences. Furthermore, these four species are important causes of fish diseases in aquaculture, and it is expected that information on the distribution, host range, and occurrence of fish diseases for each capsalid secured by molecular identification will be accumulated.The Life Science Identifier (LSID): urn:lsid:zoobank.org:pub:26C15D17-CFD1-450D-9FCE-EFFF692D2133.  相似文献   

17.
河南黄柏山国家森林公园两栖动物多样性调查   总被引:2,自引:1,他引:1  
2008 ~2010年采用踏查法和访问法对河南省黄柏山国家森林公园两栖动物资源进行调查.结果显示,黄柏山国家森林公园现有两栖动物21种,隶属于2目7科16属;区系组成以东洋界成分为主;蛙科( Ranidae)为优势科,中华蟾蜍指名亚种(Bufo gargarizans gargarizans)、黑斑侧褶蛙(Peloph...  相似文献   

18.
Paurodontella parapitica n. sp., collected from the rhizosphere of an apple tree in Kermanshah province, western Iran, is described. The new species is characterized by a body length of 505 to 723 µm (females) and 480 to 600 µm (males), lip region continuous by depression; 7 to 8 μm broad, 3 to 4 µm high, stylet length 7 to 9 µm or 1 to 1.3 times the lip region diameter, short postuterine sac of 4 to 6 μm long, lateral fields with five to six incisures; outer incisures crenated and inner incisures weakly crenated, excretory pore situated 90 to 100 µm from anterior end; functional males common in the population, with spicules 24 to 26 μm long. Tail of both sexes similar, almost straight and elongate-conoid. The new species resembles in morphology and morphometrics to four known species of the genus, namely P. apitica, P. minuta, P. myceliophaga, and P. sohailai. The results of phylogenetic analyses based on sequences of D2/D3 expansion region of 28S rRNA gene revealed this genus is polyphyletic in four different clades in Tylenchid.  相似文献   

19.
Although diverse natural products have been isolated from the benthic, filamentous cyanobacterium Lyngbya majuscula, it is unclear whether this chemical variation can be used to establish taxonomic relationships among disparate collections. We compared morphological characteristics, secondary-metabolite compositions, and partial 16S ribosomal DNA (rDNA) sequences among several collections of L. majuscula Gomont, Lyngbya spp., and Symploca spp. from Guam and the Republic of Palau. The morphological characteristics examined were cell length, cell width, and the presence or absence of a calyptra. Secondary metabolites were analyzed by two-dimensional thin-layer chromatography. Each collection possessed a distinct cellular morphology that readily distinguished Lyngbya spp. from Symploca spp. Each collection yielded a unique chemotype, but common chemical characteristics were shared among four collections of L. majuscula. A phylogeny based on secondary-metabolite composition supported the reciprocal monophyly of Lyngbya and Symploca but yielded a basal polytomy for Lyngbya. Pairwise sequence divergence among species ranged from 10 to 14% across 605 bp of 16S rDNA, while collections of L. majuscula showed 0 to 1.3% divergence. Although the phylogeny of 16S rDNA sequences strongly supported the reciprocal monophyly of Lyngbya and Symploca as well as the monophyly of Lyngbya bouillonii and L. majuscula, genetic divergence was not correlated with chemical and morphological differences. These data suggest that 16S rDNA sequence analyses do not predict chemical variability among Lyngbya species. Other mechanisms, including higher rates of evolution for biosynthetic genes, horizontal gene transfer, and interactions between different genotypes and environmental conditions, may play important roles in generating qualitative and quantitative chemical variation within and among Lyngbya species.  相似文献   

20.
The Western Ghats of India harbors a rich diversity of amphibians with more than 77% species endemic to this region. At least 42% of the endemic species are threatened due to several anthropogenic stressors. However, information on amphibian diseases and their impacts on amphibian populations in this region are scarce. We report the occurrence of Batrachochytridium dendrobatidis (Bd), an epidermal aquatic fungal pathogen that causes chytridiomycosis in amphibians, from the Western Ghats. In the current study we detected the occurrence of a native Asian Bd strain from three endemic and threatened species of anurans, Bombay Night Frog Nyctibatrachus humayuni, Leith''s Leaping Frog Indirana leithii and Bombay Bubble Nest Frog Raorchestes bombayensis, for the first time from the northern Western Ghats of India based on diagnostic nested PCR, quantitative PCR, DNA sequencing and histopathology. While, the Bd infected I. leithii and R. bombayensis did not show any external symptoms, N. humayuni showed lesions on the skin, browning of skin and sloughing. Sequencing of Bd 5.8S ribosomal RNA gene, and the ITS1 and ITS2 regions, revealed that the current Bd strain is related to a haplotype endemic to Asia. Our findings confirm the presence of Bd in northern Western Ghats and the affected amphibians may or may not show detectable clinical symptoms. We suggest that the significance of diseases as potential threat to amphibian populations of the Western Ghats needs to be highlighted from the conservation point of view.  相似文献   

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