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1.
Falcaustra desilvai sp. nov. (Ascaridida, Kathlaniidae) from the large intestine of Cnemaspis aff. tropidogaster (Squamata, Gekkonidae) is described and illustrated. Falcaustra desilvai represents the 4th nematode species from Sri Lanka to be assigned to the genus and is distinguished from other Sri Lankan species by the distribution pattern of caudal papillae (12 precloacal, 2 adcloacal, 10 postcloacal, and 1 median), length of spicules (956–1046 μm) and absence of a pseudosucker.  相似文献   

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A new species of Soboliphyme from the endemic Iberian mole (Talpa occidentalis) is described. Soboliphyme occidentalis sp. nov. can be readily distinguished from all of its congeners primarily by the position of the vulva, which clearly shows a posterior oesophageal location, and the number of male caudal papillae. S. occidentalis sp. nov. is the only species that has four pairs of caudal papillae. S. abei, S. caucasica and S. jamesoni can be distinguished from S. occidentalis sp. nov. by not having a notched sucker, the anterior position of the vulva and two polar plugs in the eggs. S. jamesoni has an armate oral sucker and longer spicule; S. caucasica a longer spicule and shorter eggs, and S. abei has shorter eggs, which separate these species from S. occidentalis sp. nov. In the rest of the species with a notched oral sucker, S. baturini and S. hirudiniformis are differentiated from S. occidentalis sp. nov. by the anterior position of the vulva, two polar plugs in the egg and the spicule length in S. baturini and S. hirudiniformis and the size of eggs in S. baturini and S. hirudiniformis. S. ataahai, S. soricis and S. urotrichi have the vulva at the oesophago-intestinal junction, 9–10 male caudal papillae (S. ataahai and S. urotrichi), absence of male caudal papillae (S. soricis), armate oral sucker and long spicule in S. ataahai and one row of six circumoral spines in S. urotrichi. A key to the species of Soboliphyme is presented.  相似文献   

4.
Lemuricola (Madoxyuris) bauchoti Chabaud, Brygoo et Petter, 1965 is redescribed from material collected from the ring-tailed lemur, Lemur catta, from the Beza Mahafaly Special Reserve in Madagascar using the scanning electron microscope. This is a new host record and the first oxyurid reported from the ring-tailed lemur. Previously, records of each species of the subgenus Madoxyuris have been restricted to a single host species, but the close relationship between these nematodes and their Strepsirrhini hosts will only be proven when additional records fill in the gaps in their distribution.  相似文献   

5.
Rhabdias mcguirei sp. nov., is described on the basis of specimens found in the lungs of northern Philippine flying lizards, Draco spilopterus (Reptilia, Agamidae) collected in Aurora province, Luzon Island, Philippines. It is characterized by a rounded oral opening, a buccal capsule consisting of anterior and posterior parts, and the shape of the cuticular inflation in the anterior part of the body: the cuticle is less inflated in the anterior-most part, with the inflation gradually thickening up to the level of the oesophageal-intestinal junction. The new species is differentiated from the 11 most closely related species of Rhabdias previously known from lizards.  相似文献   

6.
Having studied 67 birds of six species of the family Corvidae, Sarcocystis cysts were found in 16 (23.9%) individuals belonging to three species. The highest prevalence of infection (35.9%) was determined in the hooded crow (Corvus cornix). Two types of sarcocysts, which were temporarily called cysts type I and type V, were determined in the corvids examined. By light microscope, type I cyst wall seemed to be thin (< 1.0 microm) and smooth. Banana shaped cystozoites measured 6.0-8.0 microm in length. By light microscope, type V cyst wall seemed striated and reached up to 2.5 microm. Banana shaped cystozoites measured 6.1-7.9 x 1.4-1.8 microm. Ultrastructurally, the cyst wall amounted to 2.1 microm and had stump-like protrusions that differed greatly in size and shape. The parasitophorous vacuolar membrane had indentations and clearly visible (up to 0.2 microm in length) microprojections, which also differed considerably in size and shape. The ultrastructure of type V cyst wall differed from all those Sarcocystis spp. described thus far. On the basis of this-Sarcocystis cornixi sp. nov.-is proposed for this type of sarcocysts. Partial sequences of 18S rRNA and 28S rRNA genes were determined for this species and a phylogenetic analysis of the Sarcocystidae family was performed. In the phylogenetic tree, S. cornixi is grouped together with Frenkelia microti, F. glareoli, S. muris, S. neurona and the unnamed Sarcocystis species whose intermediate hosts are birds. S. cornixi is the most closely related to Sarcocystis sp. (cyst type I) from the white-fronted geese.  相似文献   

7.
A new species of dracunculoid nematode, Mexiconema africanum sp. n. (Daniconematidae), is described from the abdominal cavity and the intestine (rarely also the gall bladder) of the catfish Auchenoglanis occidentalis (Valenciennes) (Claroteidae, Siluriformes) from Lake Turkana, Kenya. The new species differs from two other congeners mainly in the absence of two large cell nuclei in the glandular oesophagus, presence of well-developed lateral cephalic elevations, more numerous (14) cephalic papillae and a much longer body of the gravid female (18–22 mm); from Mexiconema cichlasomae Moravec, Vidal and Salgado Maldonado, 1992 also in less numerous (two) caudal processes and a different arrangement of genital papillae in the male. M. africanum is the first representative of the dracunculoid family Daniconematidae described from Africa.  相似文献   

8.
All trypanosome species classified in the subgenus Herpetosoma in sciurid hosts have been recorded from ground and tree squirrels to date, but not from any flying squirrels. We describe in this paper a novel trypanosome species, Trypanosoma (Herpetosoma) kuseli sp. n., from Siberian flying squirrels (Pteromys volans) imported from China, and compare it with T. (H.) otospermophili in Richardson's ground squirrels (Spermophilus richardsonii) and Columbian ground squirrels (Spermophilus columbianus) from the USA. Due to a short free flagellum, the new species appeared stumpy compared with T. otospermophili (length of free flagellum 7.0 +/- 0.8 microm, total length 32.1 +/- 0.8 microm, n = 13 and length of free flagellum 15.5 +/- 1.6 microm, total length 35.9 +/- 1.0 microm, n = 13, respectively). Another conspicuous morphological feature of the new species was an anteriorly positioned kinetoplast, found approximately at the midpoint between the nucleus and the posterior end. These characters have not been recorded from any squirrel Herpetosoma trypanosome species. Comparison of the nucleotide sequences of the small and large subunit rRNA genes indicated that T. kuseli sp. n. was more homologous to T. otospermophili than murid Herpetosoma species, such as T. grosi, T. lewisi, T. musculi, T. microti and T. evotomys.  相似文献   

9.
A new isosporoid coccidian (Apicomplexa, Eimeriidae) species from the grey-hooded flycatcher, Mionectes rufiventris, from Brazil, is reported in the current study. Isospora mionectesi sp. nov. oocysts are ellipsoidal, 28.3 × 21.2 μm, with smooth, bilayered wall, ∼1.3 μm. Micropyle and oocyst residuum are absent, but one or two polar granules are present. Sporocysts are elongate ellipsoidal, 19.7 × 11.7 μm. Stieda body rounded and substieda body prominent. Sporocyst residuum is subspherical and compact. Sporozoites are vermiform with one refractile body and a nucleus.  相似文献   

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On the basis of the already published morphological, 18S rDNA, 28S rDNA data (Kutkienė et al., Parasitol Res 99:562–565, 2006; Parasitol Res 102:691–696, 2008; Parasitol Res 104:329–336, 2009), and ITS-1 region investigation results of sarcocysts presented in this paper, Sarcocystis albifronsi sp. nov. from the white-fronted goose (Anser albifrons) and Sarcocystis anasi sp. nov. from the mallard duck (Anas platyrhynchos) are described.  相似文献   

12.
Dracunculus brasiliensis sp. n. (Dracunculidae), is described based on a single female specimen found in the body cavity of the anaconda, Eunectes murinus (L.) (Ophidia: Boidae), from the Mexiana Island, Amazon River delta, Brazil and one female previously recorded from the subcutaneous tissue of this host species imported from South America into Europe (ZOO in the Czech Republic). The new species is characterised mainly by markedly large, anteriorly protruding dorsal and ventral double papillae of the internal circle and small lateral papillae of the same circle, a widely rounded caudal end, the excretory pore situated just posterior to the nerve ring, a distinctly transversely striated cuticle and by the length (396–429 μm) of larvae from uterus. This is the first species of Dracunculus described from reptiles in South America.  相似文献   

13.
Leishmania (Viannia) braziliensis is the major causative agent of American tegumentary leishmaniasis, a disease that has a wide geographical distribution and is a severe public health problem. The cysteine proteinase B (CPB) from Leishmania spp. represents an important virulence factor. In this study, we characterized and localized cysteine proteinases in L. (V.) braziliensis promastigotes. By a combination of triton X-114 extraction, concanavalin A-affinity, and ion exchange chromatographies, we obtained an enriched fraction of hydrophobic proteins rich in mannose residues. This fraction contained two proteinases of 63 and 43 kDa, which were recognized by a CPB antiserum, and were partially sensitive to E-64 in enzymatic assays with the peptide Glu-Phe-Leu. In confocal microscopy, the CPB homologues localized in the peripheral region of the parasite. This data together with direct agglutination and flow cytometry assays suggest a surface localization of the CPB homologues. The incubation of intact promastigotes with phospholipase C reduced the number of CPB-positive cells, while anti-cross-reacting determinant and anti-CPB antisera recognized two polypeptides (63 and 43 kDa) derived from phospholipase C treatment, suggesting that some CPB isoforms may be glycosylphosphatidylinositol-anchored. Collectively, our results suggest the presence of CPB homologues in L. braziliensis surface and highlight the need for further studies on L. braziliensis cysteine proteinases, which require enrichment methods for enzymatic detection.  相似文献   

14.
Proctocaecum blairi sp. nov. is described from specimens found in the intestine of an Australian freshwater crocodile, Crocodylus johnstoni, from Northern Territory, Australia. The most important diagnostic features of the new species are the body proportions and size, the position of the pharynx (relative length of the prepharynx and oesophagus), the relative length and position of the vitelline fields, and the number, shape and size of the circumoral spines. The new species is morphologically most similar to Proctocaecum atae, P. elongatum, P. crocodili, P. gairhei and Acanthostomum slusarskii. It differs from all of these species in having a much longer prepharynx, and differs from both P. atae and P. crocodili in having a much longer body and posteriorly situated vitelline fields. Proctocaecum blairi sp. nov. differs from P. elongatum in having a shorter body, a greater forebody to hindbody ratio, a much smaller ventral sucker, and a higher number of circumoral spines (23 vs 21 in P. elongatum). The new species differs from P. gairhei in possessing a much larger body length:width ratio and an ovary separated from the anterior testis by a seminal receptacle. Acanthostomum slusarskii lacks a gonotyl and has fewer circumoral spines than the new species. Proctocaecum blairi sp. nov. is the third species of Proctocaecum and the fourth cryptogonimid species known from crocodiles in Australia.  相似文献   

15.

Background  

Radix Wikstroemiae is a common Chinese herbal medicine. The ethyl acetate fraction of the ethanolic extract of W. indica possesses potent in vitro antiviral activity against respiratory syncytial virus (RSV). This study aims to identify the antiviral components of the active fraction.  相似文献   

16.
By light microscopy, cysts of Sarcocystis sp. (cyst type I) from the goldeneye (Bucephala clangula) seemed filamentous with a smooth and thin (<1 μm) cyst wall. Ultrastructurally, the cyst wall surface was irregular with minute undulations of the primary cyst wall. These sarcocysts had type-1 cyst wall. Cystozoites were banana-shaped and measured 7.0–8.5 μm in length. By light microscopy, cysts of Sarcocystis sp. (cyst type II) from the mallard (Anas platyrhynchos) were ribbon-shaped, very long, and thin. On the surface of the wall (up to 1.5 μm), they had palisade-like villar protrusions closely crowded together. Electron micrographs showed villar protrusions (up to 1.3 μm in length) different in size and shape. The latter had short microprojections especially obvious in the oblique sections. Cystozoites were slightly bent with blunt ends, broader at one end, and measured 13.0–16.1 × 1.8–2.5 μm. Phylogenetic analysis based on the comparison of partial 28S rRNR gene sequences of Sarcocystis sp. (cyst type II) derived from the mallard, Sarcocystis sp. (cyst type I) and Sarcocystis sp. (cyst type III) both derived from the white-fronted goose (Anser albifrons) suggested that these sequences belonged to separate Sarcocystis species.  相似文献   

17.
Galba truncatula snails were experimentally infected with either of two different isolates of Fasciola gigantica, originating from Egypt or China, to determine the influence of these isolates on the characteristics of snail infections. The survival rates of G. truncatula on day 30 post-exposure were 90.0% and 60.2% in the Egyptian and Chinese groups, respectively. The frequency of cercaria-shedding snails within the Egyptian group was 79.8%, whereas in the Chinese group it was 22.4%. The parasite origin had a significant effect on the durations of the prepatent and patent periods. The mean number of cercariae shed from the Egyptian group was significantly greater than that shed from the Chinese group (a mean of 275.5 per cercaria-shedding snail compared with 29.0). These results could be explained by the fact that G. truncatula might be a natural intermediate host for F. gigantica in Egypt, and the greater adaptability of the Egyptian miracidia of F. gigantica to unusual snail hosts. These results demonstrate the influence of the geographic origin of the parasite on the success of trematodes infecting snails.  相似文献   

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Macroderoides texanus n. sp. is described based on 16 specimens collected from the intestine of the North American alligator gar, Atractosteus spatula. Of the five established species of Macroderoides, the new species is morphologically most similar to Macroderoides spiniferus and Macroderoides trilobatus. M. texanus n. sp. differs from M. spiniferus by having the ovary situated immediately posterior to the cirrus sac rather than at mid-way between the cirrus sac and anterior testis, the ventral sucker situated further posteriorly, and the vitelline fields extending somewhat posterior to posterior testis rather than to the middle of posterior testis. M. texanus n. sp. differs from M. trilobatus by having the ovary positioned immediately adjacent to, or overlapping the cirrus sac rather than at some distance posterior to it, and by having significantly larger eggs. Additionally, the new species has two distinctive rows of spines on the postero-ventral surface of the oral sucker that are lacking in M. spiniferus and M. trilobatus. Comparison of approximately 2,700-base-pair sequences of nuclear rDNA (partial 18S, complete ITS region and partial 28S) from M. texanus n. sp., M. spiniferus and M. trilobatus, strongly supports the status of M. texanus n. sp. as a new species.  相似文献   

20.
Angiostrongylus costaricensis can infect several mollusks, and its migration route in intermediate hosts has been studied only in Sarasinula marginata. To verify the susceptibility of Omalonyx sp. as an intermediate host of A. costaricensis and to analyze the nematode migration route, individuals were infected with stage 1 larvae. Obtained stage 3 larvae were orally inoculated in mice, and after 30 days, adult worms and stage 1 larvae were recovered, demonstrating Omalonyx susceptibility and suitability to infection. To define the parasite migration routes, specimens of Omalonyx with 30 min, 1 h, 2 h, 4 h, 6 h, 8 h, 2 days, 5 days, 10 days, 12 days, 15 days, 20 days, 21 days, 25 days, 28 days, and 30 days of infection were fixed and serially sectioned. Histological sections were stained with hematoxylin–eosin. The results were compared to those described in S. marginata. Oral and cutaneous infections were noted. After the penetration, larvae were retained, mainly in the fibromuscular tissue, by hemocytes, or they spread to the whole organism through the circulation, following the anatomical structure of the vasculature. The perilarval hemocyte reaction in Omalonyx was more intense until stage 2 larva instar, decreasing in the presence of stage 3 larvae. Differences in some aspects of hemocyte reaction between S. marginata and Omalonyx exemplify interspecific peculiarities in snail response to the same parasite. Fapemig, FIOCRUZ, and Pibic UFMG.  相似文献   

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