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1.
Larvae of the cyclophyllidean tapeworms Paradilepis scolecina (Rudolphi, 1819), Neogryporhynchus cheilancristrotus (Wedl, 1855) and Valipora campylancristrota (Wedl, 1855), are described from British freshwater fish. The morphometrics of the rostellar hooks, infection characteristics and host ranges of these parasites from fisheries in England and Wales are presented. Difficulties in the detection, handling and identification of these tapeworms are highlighted, and may in part explain the paucity of records from Britain. Tissue digestion was shown to be a useful technique for the examination of these parasites, providing clear and consistent preparations of the rostellar hooks for measurement. The pathological changes caused by P. scolecina to the liver of wild tench, Tinca tinca, are detailed for the first time. Tapeworms located in the hepatic parenchyma and pancreatic tissues caused little pathological damage and invoked only mild inflammatory responses. The small size of these tapeworms and their encapsulation within host tissues appear to limit the severity of pathology, compared with parasites that insert their rostellum during attachment.  相似文献   

2.
A survey of metacestodes of dilepidid tapeworms (Cyclophyllidea) occurring in fish from Mexico is presented. They belong to the following species (those first reported from Mexico marked with an asterisk): Cyclustera capito (Rudolphi, 1819); * Cyclustera cf. ralli (Underwood & Dronen, 1986); Dendrouterina pilherodiae Mahon, 1956; * Glossocercus auritus (Rudolphi, 1819); * G. caribaensis (Rysavy & Macko, 1973); * Paradilepis caballeroi Rysavy & Macko, 1973; * Paradilepis cf. urceus (Wedl, 1855); * Paradilepis sp.; Parvitaenia cochlearii Coil, 1955; * Parvitaenia macropeos (Wedl, 1855); * Valipora campylancristrota (Wedl, 1855); * V. mutabilis Linton, 1927; and * V. minuta (Coil, 1950). Metacestodes of Dendrouterina papillifera (Fuhrmann, 1908), previously reported from the gall-bladder of the pimelodid catfish Rhamdia guatemalensis from Mexico by Scholz et al. (1996), belong actually to V. minuta. Data on the morphology of metacestodes, their fish hosts and rate of infection, site and distribution in Mexico are provided.  相似文献   

3.
R. Kfir 《BioControl》1997,42(4):517-523
Larvae and pupae of diamondback moth,Plutella xylostella (L.) (Lepidoptera: Plutellidae), were collected weekly for two years on unsprayed cabbage plots. Samples were taken to the laboratory and parasitoids that emerged were identified and their incidence determined. Parasitoids were active throughout the year and parasitism was high (reaching 90–100%) except in the winter months of June–August when it was low. Twenty one species were reared: the egg-larval parasitoidsChelonus curvimaculatus Cameron and Chelonus sp. (Braconidae); the larval parasitoidsApanteles eriophyes Nixon,Cotesia plutellae (Kurdjumov),Habrobracon brevicornis (Wesmael) (Braconidae) andPeribaea sp. (Tachinidae); the larvalpupal parasitoidsDiadegma sp.,Itoplectis sp. (Ichneumonidae) andOomyzus sokolowskii (Kurdjumov) (Eulophidae); the pupal parasitoidsBrachymeria sp.,Hockeria sp. (Chalcididae),Diadromus collaris Gravenhorst (Ichneumonidae) andTetrastichus howardi (Olliff) (Eulophidae); and the hyperparasitoidsAphanogmus fijiensis (Ferrière) (Ceraphronidae),Brachymeria sp.,Hockeria sp.Proconura sp. (Chalcididae),Mesochorus sp. (Ichneumonidae),Pteromalus sp. (Pteromalidae),Eurytoma sp. (Eurytomidae) andTetrastichus sp. (Eulophidae).  相似文献   

4.
Interrelationships of the tapeworms (Platyhelminthes: Cestoda) were examined by use of small (SSU) and large (LSU) subunit ribosomal DNA sequences and morphological characters. Fifty new complete SSU sequences were added to 21 sequences previously determined, and 71 new LSU (D1-D3) sequences were determined for the complementary set of taxa representing each of the major lineages of cestodes as currently understood. New sequences were determined for three amphilinidean taxa, but were removed from both alignments due to their excessively high degree of divergence from other cestode sequences. A morphological character matrix coded for supraspecific taxa was constructed by the modification of matrices from recently published studies. Maximum-parsimony (MP) analyses were performed on the LSU, SSU, LSU+SSU, and morphological data partitions, and minimum-evolution (ME) analyses utilizing a general time reversible model of nucleotide substitution including estimates of among-site rate heterogeneity were performed on the molecular data partitions. Resulting topologies were rooted at the node separating the Gyrocotylidea from the Eucestoda. The LSU data were found to be more informative than the SSU data and were more consistent with inferences from morphology, although nodal support was generally weak for most basal nodes. One class of transitions was found to be saturated for comparisons between the most distantly related taxa (gyrocotylideans vs cyclophyllideans and tetrabothriideans). Differences in the topologies resulting from MP and ME analyses were not statistically significant. Nonstrobilate orders formed the basal lineages of trees resulting from analysis of LSU data and morphology. Difossate orders were basal to tetrafossate orders, the latter of which formed a strongly supported clade. A clade including the orders Cyclophyllidea, Nippotaeniidea, and Tetrabothriidea was supported by all data partitions and methods of analysis. Paraphyly of the orders Pseudophyllidea, Tetraphyllidea, and Trypanorhyncha was consistent among the molecular data partitions. Inferences are made regarding a monozoic (nonsegmented) origin of the Eucestoda as represented by the Caryophyllidea and for the evolution of the strobilate and acetabulate/tetrafossate conditions having evolved in a stepwise pattern.  相似文献   

5.
用透射电镜观察了扩张莫尼茨绦虫(Moniezia expansa)卵黄细胞发育的全过程。扩张莫尼茨绦虫卵黄细胞发育的规律为:(1)细胞体积不断增大;(2)质、核比不断增加而核体积几乎不发生改变,核表面从规则变为不规则,再由不规则变为规则,核内出现染色质浓缩成小块再分散的发育变化过程;(3)线粒体逐渐增多,发育不断完善;(4)粗面内质网及高尔基复合体出现由少到多,发育不断完善,再由多到少不断退化的变化;(5)由高尔基复合体组装的电子致密的小卵黄囊不断融合,至卵黄细胞成熟时仅有一卵黄囊,占据细胞大部分体积[动物学报49(2):256—261,2003]。  相似文献   

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Methods for the collection, fixation, preservation and examination of the cestodes parasitic in British freshwater fishes are described. An illustrated key to the species is provided, with the exception of the members of the genus Proteocephalus , for which the information is tabulated.  相似文献   

9.
Cestodes are reported from Didelphis albiventris Lund, 1840 and Micoureus cinereus Temminck, 1824 (Marsupialia: Didelphidae) in Argentina. These include a new species of Mathevotaenia Akhumyan, 1946 (Cestoda: Anoplocephalata) as well as M. bivittata (Janicki, 1904) and an unknown hymenolepidid cestode. Mathevotaenia argentinensis n. sp. is characterized by a relatively narrow strobila, 18-37 mm in total length and 1.0-1.5 mm in maximum width, 135-163 craspedote proglottids, 19-27 testes, and a muscular genital atrium. This species differs from M. didelphidis (Rudolphi, 1819) in the disposition of the genital ducts between the excretory canals and in the entrance of the vagina into the genital atrium posterior to the cirrus pouch; from M. paraguayae Schmidt and Martin, 1978 in the disposition of the genital ducts, absence of a seminal receptacle, and presence of an armed cirrus; and from M. boliviana Sawada and Harada, 1986 and M. pennsylvanica Chandler and Melvin, 1951 in the presence of an armed cirrus. Linstowiines appear to be the dominant cestodes in New World marsupials, with M. bivittata representing the most prevalent and widely distributed species. The hymenolepidid is the first record of this family in Neotropical marsupials.  相似文献   

10.
Karyotypes of three dilepidid species: Molluscotaenia crassiscolex, Anomotaenia bacilligera and Dilepis undula, which have not been recorded previously, were studied using conventional Giemsa staining and comparative karyometric analysis. Twelve small biarmed chromosomes were observed in mitotic cells of M. crassiscolex, 16 biarmed chromosomes of gradually decreasing size were found in cells of A. bacilligera, while 18 elements were characteristic for D. undula. These data, together with information available in literature, prove the heterogeneity and possible polyphyletic nature of the family Dilepididae.  相似文献   

11.
There has been no previous systematic statewide study of mosquitoes in Mississippi. This survey, resulting in the collection of over 400,000 specimens, was conducted by the authors from 2003 to 2007 throughout much of the state using CO2‐baited CDC light traps and larval dipping. In addition, a health department contract mosquito surveillance technician collected several thousand specimens from the state from 2001 to 2003. Lastly, specimens housed at the Mississippi State University Entomological Museum, obtained from previous surveys, were included as vouchers for species occurring in the state. The collection records and literature show 60 species as occurring or having occurred in Mississippi. Voucher specimens representing 57 of the 60 species discussed are deposited in the Mississippi Entomological Museum or in the U.S. National Museum of Natural History (USNM), Washington, D.C.  相似文献   

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13.
A checklist of tapeworms (Cestoda) of vertebrates (fishes, birds and mammals) in Finland is presented, based on published observations, specimens deposited in the collections of the Finnish Museum of Natural History (Helsinki) and the Zoological Museum of the University of Turku, and additional specimens identified by the present author. The checklist includes 170 tapeworm species from 151 host species, comprising 447 parasite species/host species combinations. Thirty of the tapeworm species and 96 of the parasite/host species combinations have not been previously reported from Finland. The total number of tapeworm species in Finland (170 spp.) is significantly lower than the corresponding figure for the Iberian Peninsula (257 spp.), Slovakia (225 spp.) and Poland (279 spp.). The difference between Finland and the other three regions is particularly pronounced for anseriform, podicipediform, charadriiform and passeriform birds, reflecting inadequate and/or biased sampling of these birds in Finland. It is predicted that there are actually ca. 270 species of tapeworms in Finland, assuming that true number of bird tapeworms in Finland corresponds to that in other European countries with more comprehensive knowledge of the local tapeworm fauna. The other main pattern emerging from the present data is the seemingly unexplained absence in (northern) Fennoscandia of several mammalian tapeworms that otherwise have extensive distributions in the Holarctic region or in Eurasia, including the northern regions. Previously unknown type specimens, that is, the holotype of Bothrimonus nylandicus Schneider, 1902 (a junior synonym of Diplocotyle olrikii Krabbe, 1874) (MZH 127096) and the syntypes of Caryophyllaeides fennica (Schneider, 1902) (MZH 127097) were located in the collections of the Finnish Museum of Natural History.  相似文献   

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Fine structure of genital atrium, Furman body, distal region of vagina and sac cirrus were investigated. The broad polymorphism of surface microstructures (microtriches) in various parts of copulative apparatus has been revealed. The constitution of prostate glands, being the modified cytons of syncitial epithelium of the intrabursal section of spermaduct wall, is described. Based on obtained and reference data, a comparative morphological analysis of copulative apparatus organization in lowest and highest cestodes was carried out. The hypothesis suggests that evolution of its organization was connected with the reduction of the muscular elements and simultaneous improvement of their managing, their isolation from surrounding parenchyma and development of supporting connective tissue elements. It is shown, that Fuhrmann's body has its own developed muscular system armed with power microtriches and being capable to evaginate into the distal region of vagina. It is supposed that S. gracilis obtains of two different ways of copulation in: by means of cirrus that executes the cross fertilization; and by means of the additional copulative formation--Furman body, which guarantees the self fertilization of worms.  相似文献   

17.
Summary

Transmission electron microscopy revealed that the eggs of Mesocestoides lineatus consisted of an oncosphere larva surrounded by various coverings. The outermost of these was the embryonic capsule, which appeared as a thin electron-dense membranous sac. The capsule enclosed inner and outer embryonic envelopes, each of which was syncytial and apparently formed from embryonic blastomeres. The envelopes became increasingly vesiculated during embryogenesis, and were attached to each other by desmosomes by the time the larva was fully formed. An electron-dense intracellular embryophore was produced by the inner envelope; it first appeared under the distal plasma membrane as a series of blocks, which grew and fused to form a thick unbroken layer. Early in development, the proximal plasma membrane of the inner envelope was connected to the larval epithelium by a multilaminate membrane complex that was ultrastructurally similar to a continuous junction. At the end of embryogenesis, this appeared to detach from its formative cells on both sides to form the distinctive oncospheral membrane. Several eggs were bound together in clusters by a cluster capsule that was ultrastructurally identical to the individual embryonic capsules. This type of egg packaging has not been described previously for any cestode. Both the cluster and individual capsules broke down by the end of embryogenesis.  相似文献   

18.
Microtriches on the scolices and adjacent strobila of seven species of diphyllobothriidean cestodes (Bothridium pithonis, Cephalochlamys namaquensis, Dibothriocephalus latus, Duthiersia expansa, D. fimbriata, Ligula intestinalis, and Schistocephalus solidus) from different hosts (frogs, snakes, lizards, birds, and mammals) and biogeographic areas were examined using scanning and transmission electron microscopy. The basic structure of the tegument of the seven species studied does not differ markedly from that found in other cestodes. The main characteristic is the presence of electron‐dense bodies and vesicles in the distal cytoplasm. However, this study has shown differences in the morphology of microtriches even among species of the same family. Two different types of microtriches were found, filitriches and spinitriches, with the latter represented by two forms. Our study reveals that capilliform filitriches are most commonly found in Diphyllobothriidea. They were observed mainly on the strobila and the scolices of all but one studied species; individuals of L. intestinalis bore only coniform spinitriches on their surface. The same type of microtriches was found on the cirrus in D. latus. Gladiate spinitriches covered the scolex in both species of Duthiersia, and gladiate spinitriches interspersed with capilliform filitriches were observed on the anterior part of the strobila in D. fimbriata and the posterior part of the scolex in B. pithonis. Individuals of C. namaquensis were covered only by small acicular filitriches. No obvious pattern in the type and distribution of microtriches was observed among species that belong to different families and parasitize distantly related definitive hosts.  相似文献   

19.
Cysticercoids of the cestode Unciunia raymondi Gigon et Beuret, 1991 (Cyclophyllidea: Dilepididae), a parasites of palaearctic thrushes (Turdus), taken from spontaneously infected Geotrupes and black wireworm Cylindrojulus in the North-eastern Altai, is described. An identity of cysticercoids of U. raymondi and Ditestolepis diaphana sensu Kisilewska, 1960 has been stated. During the development within the fibrillate membrane, the metacestode of U. raymondi separates the cercomer from the cyst anlage in the late scolexogenesis. There is no the primary lacuna in the lamellated cercomer without any musculature. Its primarily smooth surface gradually becomes sulcate and plicate. In the result of some segments break-up, the cercomer lamella comes to be perforated with its margins deeply jagged. Metacestode of U. raymondi metacestode is compared with cryptocercus of Dilepididae, which also develops within the fibrillate membrane. Based on peculiarities of the morphogenesis of cercomer, the cysticercoid U. raymondi is assigned to a new morpho-ecological type, the placocercus.  相似文献   

20.
In all, 80 species and varieties of marine algae are recorded from the intertidal region of the Visakhapatnam coast. Of these, 18 are new records for India and seven are first records for the east coast. Information on the localities of their occurrence and notes on the morphology and other features of taxonomic interest are given in the annotations.  相似文献   

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