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1.
Regel' KV 《Parazitologiia》2001,35(2):114-123
Four species of the genus Echinatrium Spassky et Jurpalova, 1965 are redescribed. The material was collected from ducks of the Chaunskaya lowland (Chukotka). Morphological study of genital apparatus in cestode species found was carried out. According to the priority rule, it is suggested that the genus Monosaccanthes Czaplinski, 1967 is a junior synonym of the genus Echinatrium.  相似文献   

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Microsomacanthus diorchis (Fuhrmann, 1913) is redescribed and illustrated on the basis of the type-material and new findings from common eider Somateria mollissima captured in Iceland and specimens from the same host species from the Barents, White and Bering Seas. A lectotype is designated and an amended diagnosis is provided. The main differentiating features of M. diorchis are the size and shape of rostellar hooks and the cirrus, the well-marked delay in the antiporal testis development and the bow-shaped uterus. This parasite is shown to be specific to S. mollissima for both Atlantic and Pacific populations of the host. Hymenolepis (Microsomacanthus) somateriae of Bishop & Threlfall (1974) [nec M. somateriae Ryzhikov, 1965] is recognised as a synonym of M. diorchis (Fuhrmann, 1913). The taxonomic position of the species described as Aploparaksis murmanica Baylis, 1919 from common eider is discussed.  相似文献   

4.
A new genus and species of cestodes from the great-crested grebe Podiceps cristatus collected in the Eastern Europe is described. The genus Mircia gen. n. in addition to the type species M. shigini gen. n. includes the following species formerly being included in the genus Joyeuxilepis Spassky, 1947: M. decacantha (Fuhrmann, 1913) comb. n., M. decacanthoides (Borgarenko et Gulyaev, 1991) comb. n., M. fimbriata (Borgarenko, Spasskaja et Spassky, 1972), comb. n., and M. uralensis (Gulyaev, 1989) comb. n. Brief revision of the genus Joyeuxilepis is provide.  相似文献   

5.
Adults of Profilicollis botulus were found in 6 species of diving ducks in British Columbia including 3 new hosts: common goldeneye, Bucephala clangula (L.); Barrow's goldeneye, B. islandica (Gmelin); and greater scaup, Aythya marila (L.). The identification of the species was verified by the examination of co-types and specimens from eider ducks, Somateria mollissima (L.), from Scotland and oldsquaw, Clangula hyemalis (L.), from New Brunswick. Cystacanths from the hairy shore crab, Hemigrapsus oregonensis (Dana), were similar in morphology to those from Carcinus maenas (L.) from Scotland.  相似文献   

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A new genus and two new species of ducks (Aves: Anatidae) from the Middle Miocene Sharga locality are described. Mioquerquedula minutissima gen. et sp. nov. is a very small duck. Anas velox Milne-Edwards, 1868 from the Middle Miocene of France is transferred to the genus Mioquerquedula. Aix praeclara sp. nov. described here is the oldest record of the modern genus Aix. A revision of the previously described small duck Anas soporata Kurochkin, 1976 shows that only the specimens from the Sharga locality should be referred to this species. The status of other small ducks from the Neogene of Europe and North America is discussed. The diversity of herbivorous and diving ducks in the Sharga locality indicates that Miocene Shargyn Govi Lake was rich in food resources.  相似文献   

9.
A re-evaluation of the evolutionary stages in modern ducks and flamingos is permitted by recent discoveries of large concentrations of the Eocene avian fossil Presbyornis pervetus from Wyoming.Presbyornis was originally described as a new family, genus and species of recurvirostrid shorebird. Recent discoveries of nearly complete elements (including the skull) of this species show it to be a mosaic, combining characters primarily of the modem avian orders Charadrii-formes (shorebirds), ducks and allies (Anseriformes), and living flamingos (Phoenicopteriformes). Thus, living flamingos are mosaics, combining characters primarily of the shorebirds and the ducks and allies. Presbyornis is probably a temporal relict (like the anthracosaur Seymouria), structurally close to the ancestry of both modern ducks and modern flamingos, and was derived from shorebird ancestry.  相似文献   

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Larvae of A. birulai from Lumbriculus variegatus and A. brachyphallos from Stylodrilus sp. from the Chauna lowland (Chukotka) are described. The species belonging of the larvae was proved experimentally. It was shown that Cysticercus sp. Hrabe, 1958 is a larvacyst of A. birulai. For larvacysts of A. birulai type the name of "floricerk" was suggested and for those of A. brachyphallos type--the name "tailed diplocyst". It is noted that A. uelcal Spassky et Jurpalova, 1968 is a synonym of A. brachyphallos (Krabbe, 1869) nec A. brachyphallos sensu Davies, 1938.  相似文献   

12.
Dickinson JL 《Molecular ecology》2007,16(13):2610-2612
Conspecific brood parasitism, where females of the same species lay eggs in each other's nests, is common in waterfowl, and is usually considered costly to host females, which are stuck looking after eggs and chicks that are not their own. However, since female waterfowl often exhibit an unusual propensity to nest near where they were born, there has been some uncertainty over whether, in ducks and geese, laying in nests of conspecifics really is parasitism. Do parasitic and host females tend to be related? And is parasitism actually a form of cooperation in disguise? In a population in Hudson Bay, Andersson & Waldeck (this issue) found that ‘parasitic’ eggs in nests of the common eider, Somateria mollissima sedentaria, are more closely related to host eggs than expected by chance. In fact, host and ‘donor’ eggs are more closely related than are females breeding at neighbouring nests. The Hudson Bay population of common eiders is unusual, because unlike in more benign climates, females do not tend to breed near their natal nest. Spatial proximity alone cannot account for the high relatedness between host eggs and ‘dumped’ or donor eggs. Instead, the high relatedness values are probably the result of active recognition, where females favour kin, either when dumping or accepting eggs. These new data, along with evidence indicating that the donor lays the first egg in the nest nearly half the time, suggest that what appears to be parasitism in common eiders may be a form of kin‐based cooperation.  相似文献   

13.
Gerasev PI 《Parazitologiia》2004,38(5):426-437
A phylogenetic reconstruction of the monogenean family Tetraonchidae was carried out by methods of parsimony-based cladistics. The analysis included 20 species of tetraonchids and two out-groups (Sundanonchus tomanorum and Dactylogyrus amphibothrium) and was based on 34 morphofunctional characters. Software PAUP 4.0 and Winclada were used for the phylogenetic reconstructions. Obtained results allow proposing a preliminary phylogenetic hypothesis of the family Tetraonchidae along with the discussion of host-parasite association. According to the current taxonomic view, the family Tetraonchidae included two genera. Cladistic analysis showed a monophyly of the family and the genus Tetraonchus Diesing, 1858. Two representative of the former genus, Tetraoncus monenteron and T. borealis, parasitize the pikes (Esocoformes: Esocidae) and the grayling (Salmonidae: Thymallinae) respectively. The genus Salmonchus Spassky et Roytman, 1958 has a complicated structure and its intrageneric relationships were not completely resolved; in general, the analysis allows to recognise several species groups: Salmonchus oncorhynchi--the parasite of the Oncorhynchus masou smolt living during the first year of life in fresh water; four species (S. variabilis, S. gussevi, S. grumosus, S. alaskensis) inhabiting specifically the whitefishes (Salmonidae: Coregoninae); all reminder of Salmonchus species occurring on the salmons (Salmonidae: Salmoninae). The bootstrap test gives a support only for the following clades: family Tetraonchidae (75%), genus Tetraonchus (88%); a group of Salmonchus species associated with the whitefishes (93%) and grouping of four species (S. huhonis, S. pseudolenoki, S. skrjabini and S. lenoki) from the lenoks (Brachymystax) and taimens (Hucho) (61%).  相似文献   

14.
Over the past 20 yr, recurrent late-summer mortality of dabbling ducks in southern Québec has been attributed to the digenean parasite Cyathocotyle bushiensis. This study attempted to determine whether this parasite was still implicated in the epizootics, and examined aspects of the ecology of the parasite in the definitive host. Comparison of prevalence and mean intensity of infection of all species of Digenea between salvaged carcasses and hunter-shot ducks revealed that C. bushiensis and a second digenean Sphaeridiotrema globulus were both significantly more prevalent in salvaged ducks. Mean intensity of infection was consistently higher for S. globulus in the salvaged carcasses than in hunter-shot ducks. These data provide strong circumstantial support for the hypothesis that C. bushiensis continues to contribute to the annual mortality, but also strongly suggest that S. globulus may be involved. Comparison of the relative numbers of each species of duck between the salvaged carcass sample and the hunter-shot sample revealed that blue-winged teal (Anas discors) occurred significantly more frequently in the salvaged carcass sample whereas wood ducks (Aix sponsa) were common in the hunter-shot sample but were never found in the salvaged carcass sample. A comparison of susceptibility to experimental infection with C. bushiensis revealed that mallards (Anas platyrhynchos), black ducks (Anas rubripes), blue-winged teal, pintail (Anas acuta) and lesser scaup (Aythya affinis) had similar susceptibilities but that wood ducks were significantly less susceptible to infection. Experimental infections also showed that age of mallards significantly influenced the number of parasites obtained 7 days postinfection; ducklings were most heavily infected. Significant differences were detected in the gross pathology caused by C. bushiensis among duck species. Data obtained from sentinel ducks placed in the field for 24 hr revealed that transmission of both C. bushiensis and S. globulus occurs at least between mid-May and mid-September and that large, potentially lethal, infections can be acquired in as little as 24 hr. Finally evidence is presented to suggest that ducks acquire resistance to challenge infections of C. bushiensis.  相似文献   

15.
Analysis of the taxonomic position of most species and forms of the char (genus Salvelinus, Salmonidae: Teleostei) was made based on RAPD-PCR. The material was represented by samples from 29 populations from the Kuril Islands, coast of the Sea of Okhotsk, Kamchatka, Chukotka, Taymyr, Transbaikalia, the Kola Peninsula, Svalbard, Finland, and North America. It was shown that the genus Salvelinus splits into three well-justified clusters: (1) all the forms assigned to the Salvelinus alpinus--S. malma complex; (2) two samples of the White-Spotted Char from the Southern Kuril Islands and from Kamchatka; (3) two North American species, S. fontinalis and S. namaycush (samples of the North American species S. confluentis were absent from the collection). Analysis of the absolute values of genetic disctances of the S. alpinus--S. malma forms relative to S. leucomaenis, S. fontinalis, and S. namaycush revealed distances approaching the species rank between the following isolates: Frolikh Char, Mountain Char, Black Lake Char, Goggle-Eyed Char, and Neyva Char. Samples of Dolly Varden currently considered as "S. malma", do not constitute a separate cluster, falling within the group of the Arctic char S. alpinus. This conclusion is supported by the analysis of the results of three series of experiments by R. Phillips on ITS1 ribosome genes (Pleute et al., 1992; Phillips et al., 1995; Phillips et al., 1999). This indicates the infraspecific rank of malma within S. alpinus. Isolated populations of "Salvethymus svetovidovi" from the lake Elgygytgyn (Chukotka Peninsula) and of the char from the lake Chyornoye (Onekotan Island), recently described as S. gritzenkoi (Vasil'eva, Stygar, 2000), fell withing the S. alpinus--S. malma complex, the Onekotan char grouped together with another isolate from the same island. Comparison of genetic distances between the samples showed that the differences between the two isolated of Onekotan and migratory forms of the Kuril Islands are approximately equal, yet the homogeneity of the Chyornoye sample is higher than that of the other samples. The revealed 330-nucleotide diagnostic sequence of the Onekotan lake isolate showed identity of part of the fragment with a section of expressed DNA from the library of EST clones derived from the gills of Salmo salar, this possibly indicates the adaptive character of the evolution.  相似文献   

16.
Data are presented on the life-cycles and the postembryonal development of four species of Branchiopodataenia Bondarenko & Kontrimavichus, 2004, B. anaticapicirra Bondarenko & Kontrimavichus, 2004, B. arctowskii (Jarecka & Ostas, 1984), B. haldemani (Schiller, 1951) and B. pacifica (Spassky & Jurpalova, 1968), which are specific parasites of gulls. The investigation was carried out in Chukotka (Chaun Bay) between 1971 and 1981 under natural and experimental conditions. Branchiopod crustaceans were exclusive natural and experimental intermediate hosts of all of the species studied; this fact provided additional evidence for the erection of Branchiopodataenia. The metacestodes exhibit a pattern of postembryonal development and a typical larval form, termed a 'cercocyst', which is a modification of a cysticercoid. This modification of the metacestode does not occur in species of Wardium Mayhew, 1925, the genus with which species of Branchiopodataenia had previously been affiliated.  相似文献   

17.
记述我国树甲族1新纪录属和2新种并提出2种新名。模式标本均保存在河北大学博物馆。 Eucrossoscelis Nakane,1963中国新纪录 梭形真树甲,新种Eucrossoscelis hastatus sp.nov.(图1~8,20) 正模♀,贵州省道真县程家山,2004—05—24,于洋采。新种与分布于日本的E.araneiformis相似,但前者的头部和前胸背板的刻点不同,前胸背板光滑,刻点细小,侧缘饰边完整,端部钝尖;而后者的这几点都与之不同。种名来自它的梭形身体。 武夷山树甲,新种Strongylium wuyishanense sp.nov.(图9-19,21) 正模♂,福建省武夷山黄岗山,2004—05—21,苑彩霞、李静采。新种与云南鸡足山的细长树甲S.jizushanense Masumoto,1999相似,与后者的主要区别是:复眼较小、眼间距较宽,前胸背板的刻点小而稀疏,鞘翅刻点行上有较稀疏的刻点。这几点与后一种均有不同。种名来自模式标本产地。 Strongylium masumotoi Yuan et Ren,2005 nom.nov.Yuan et Ren,2005.Acta Zootaxonomica Sinica,30(2):401.[nec Maeiklin,1864] Strongylium obscuratum Yuan et Ren,2005 nom.nov.Yuan et Ren,2005.Acta Zootaxonomica Sinica,30(2):402.[nec Maeiklin,1864]  相似文献   

18.
Medium-sized diving ducks from the Middle Miocene of the Sharga locality (western Mongolia) are described. Sharganetta mongolica gen. et sp. nov. and Nogusunna conflictoides gen. et sp. nov. are evolutionary more advanced than the thoroughly studied Early Miocene genus Mionetta, but more primitive than Anatinae and Oxyurinae. The humeral morphology gives evidence of an aberrant position of the two new genera. Another taxon, Protomelanitta gracilis gen. et sp. nov. presumably belongs to basal Mergini.  相似文献   

19.
The classical and numerical taxonomy, palynology and the geographical distribution of the Genus Schizopepon are dealt with in the present paper. Having commented on various opinions regarding the systematic position of the genus, the present authors consider that C. Jeffrey’s treatment of Schizopepon as a new and monogeneric tribe, Schizopeponeae, should be supported. The gross morphological characters in the genus are assessed from the taxonomic point of view. Some characters, such as stamens with an elongated connective or not, different insertions of ovules and various forms of ovaries and fruits, may be used for distinguishing subgenera. The pollen grains of all the species were observed under light microscope (LM) and scanning electron microscope (SEM). The results show that a strong differentiation has taken place in the pollen of the genus, and in consequence it may be regarded as an important basis for dividing subgenera and species. Especially it should be pointed out that degrees of development of colpi and positions of ora are positively correlated with the external characters used for distinguishing subgenera. According to the morphological and palynological characters, the genus Schizopepon may be divided into three subgenera and eight species: 1. Subgenus Schizopepon: 5 species, S. bryoniaefolius Maxim., S. monoicus A. M. Lu et Z. Y. Zhang, S. dioicus Cogn., S. longipes Gagnep. and S. macranthus Hand.-Mazz.; 2. Subgenus Rhynchocarpos A. M. Lu et Z. Y. Zhang: 1 species, S. bomiensis A. M. Lu et Z. Y. Zhang; 3. Subgenus Neoschizopepon A. M. Lu et Z. Y. Zhang: 2 species, S. bicirrhosus (C. B. Clarke) C. Jeffrey and S. xizangensis A. M. Lu et Z. Y. Zhang. The 8 OTU’s including all the species of this genus and 31 characters, of which 16 are morphological characters and 15 palynological characters, were used in the numerical taxonomic treatment. After standardization of characters, the correlation and distance matrices were computed. The correlation matrices are made to test the various clustering methods. At last, the UPGMA clustering method was selected and its result is shown in the form of phenogram. The result of numerical analysis is similar to that of the classical classification. Schizopepon Maxim. is a genus of East Asia-Himalayan distribution. China has all 8 species and 2 varieties, of which 6 species are endemic. Based on the statistics of spedies number, the distribution centre of the genus is considered to be in the Hengduan Mountains (Yangtze-Mekong-Salwin water divides) and the adjacent areas of the southwest China.  相似文献   

20.
In this study, we analyzed 93 whole genomes from Chinese spot-billed ducks (CSB), meat-type ducks (MET), and egg and dual purpose-type ducks (EDT) to characterize the genetic material flowing between the CSB and modern ducks. Using a frequency of shared identical-by-descent method, approximately 10.9 Mb introgression segments containing 140 genes were identified showing the signatures of introgression between CSB and EDT. Meanwhile, nearly 10.6 M introgression regions containing 149 genes were identified between CSB and MET. Based on the haplotypes tree of each segment, we found that the introgression between CSB and domesticated ducks was asymmetric with a high level of gene flow from domestic to CSB and a low level of migration in the opposite direction. Moreover, we identified several genes that were introgressions from CSB and showed the signature of positive selection, which may contribute to the breeding of modern ducks. Our results provide new insight into the evolution and breeding history of domestic ducks and may be useful for the future management of wild and domestic duck populations.  相似文献   

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