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1.
The unusual yellow‐finned morph of European perch Perca fluviatilis found in Lake Constance suffers more severely from macroparasite infections, including the tapeworm Triaenophorus nodulosus and the gill worm Ancyrocephalus percae, than conspecifics elsewhere. Microsatellite analysis of yellow‐finned P. fluviatilis and red‐finned variant recently discovered in Lake Constance revealed significant genetic differentiation. Red‐finned P. fluviatilis and fish with mixed fin colour, suggested backcrosses between red and yellow‐finned colour morphs, exhibit better resilience to parasite infection, suggesting that the inability of the yellow‐finned morph to reject macroparasites may have a genetic basis.  相似文献   

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During a survey of fish ectoparasites in Lake Kariba (Zimbabwe), two crustaceans were often encountered. Dolops ranarum (Branchiura), parasite of the body, mouth and gill chamber, infected mostly cichlids, the catfish Clarias gariepinus, Synodontis zambezensis and two Mormyrids. Among cichlids clear host preferences were shown. No seasonal variations could be detected in the infections. D. ranarum parasitized predominantly fish above 15 cm in standard length. Lamproglena monodi (Copepoda) parasitized only the gills of cichlids with a preference for Serranochromis codringtonii, S. macrocephalus and Tilapia rendalli. Small fish were seldom infected. Seasonal variations of the prevalence occurred, the hot season being the less favourable. Few other crustaceans were found during the survey: a single specimen of Lamproglena hemprichii on the gills of the tigerfish, Hydrocynus vittatus; three specimens of Afrolernaea longicollis, one found on the gills of Hippopotamyrus discorhynchus and two on the gills of Mormyrops deliciosus; a hundred of Ergasilus mirabilis in a specimen of H. discorhynchus.  相似文献   

4.
A survey of adults of dilepidid tapeworms (Cyclophyllidea) from piscivorous birds from Mexico is presented on the basis of the taxonomic evaluation of freshly collected and voucher specimens. The following species are reported (first records from Mexico marked with an asterisk): Cyclustera capito (Rudolphi, 1819); * C. ibisae (Schmidt & Bush, 1972); * Dendrouterina ardeae Rausch, 1955; * D. herodiae Fuhrmann, 1912; * D. papillifera (Fuhrmann, 1908); Glossocercus auritus (Rudolphi, 1819); * Neogryporhynchus cheilancristrotus (Wedl, 1855); Paradilepis caballeroi Rysavy & Macko, 1973; Paradilepis sp.; Parvitaenia cochlearii Coil, 1955; and Valipora mutabilis Linton, 1927. Dendrouteria herodiae is reported from America for the first time. New definitive hosts are Phalacrocorax olivaceus for C. capito, N. cheilancristrotus and P. caballeroi; Casmerodius albus and Egretta thula for G. auritus; and E. thula for D. herodiae. Data on the morphology of the rostellar hooks of all species, their hosts and distribution in Mexico are provided.  相似文献   

5.
The Iberian and North African populations of reed warblers have been described recently as a separate taxon, ambiguus, forming a sister clade to the Sahelian subspecies minor of African Reed Warbler Acrocephalus baeticatus. Although the breeding range of ambiguus has been identified, the migration strategy of its populations remained unknown. We deployed geolocators and sampled the innermost primary from breeding adults in Spain for stable hydrogen (δ2H) analyses and also analysed stable carbon (δ13C) and nitrogen (δ15N) isotopes in feathers collected in two reed warbler taxa (Acrocephalus scirpaceus and Acrocephalus baeticatus ambiguus) in Morocco, to identify the moulting and wintering sites of these populations. Ring recoveries, geolocator tracks and probabilistic assignments to origin from δ2H values indicate that Spanish ambiguus are likely to moult south of the Sahara and winter in West Africa, probably from Mauretania to southern Mali and Ivory Coast. Moroccan ambiguus, however, undergo post-breeding moult north of the Sahara, and possibly then migrate to West Africa. With other populations of ambiguus breeding from Algeria to Libya and probably wintering further east in the Sahelian belt, the Barbary Reed Warbler can therefore be considered a trans-Saharan migrant, with a post-breeding moult strategy that varies between populations, and probably structured according to breeding latitude.  相似文献   

6.
Six new species of the genus Phortica are described from Yunnan, Southwest China: P. (Alloparadisa) kaibangya n. sp., P. (Ashima) semiannulata n. sp., P. (Ashima) dianmianensis n. sp., P. (Ashima) idiasta n. sp., P. (Ashima) menglian n. sp. and P. (Ashima) zhangyuanae n. sp. The 22 new DNA sequences of the mitochondrial COI gene with BOLD Process ID and GenBank accession numbers are provided for the six new species and six related known species from southern China: P. (Ashima) glabra, Chen & Toda, 2005 P. (Ashima) nudiarista Cheng & Chen, 2008, P. (Ashima) saltiaristula Chen & Wen, 2005, P. (Ashima) spinosa, Chen & Toda, 2005 P. (Ashima) symmetria Chen & Toda, 2005 and P. (Ashima) yiqini Zhu & Chen, 2017. The pairwise interspecific K-2P COI distances among all Chinese species of the subgenera Alloparadisa and Ashima are summarized. An identification key to males of all Chinese species of the subgenera Alloparadisa and Ashima is provided.  相似文献   

7.
The relationship between three genera considered basal in the Chromodorididae (Cadlina, Tyrinna, Cadlinella) has not yet been resolved by traditional morphological means. Here we examined the sperm ultrastructure of Tyrinna nobilis, Tyrinna evelinae, Cadlina flavomaculata and Cadlina cf. nigrobranchiata, with the expectation of finding phylogenetically informative characters. No Tyrinna or Cadlina species showed sperm similarities to Cadlinella. Both Cadlina species and Tyrinna nobilis (but not T. evelinae) exhibited coarse striations in the acrosomal pedestal. The putative fibers that occurred between the coarse striations of the pedestal are condensed into a layer in Cadlina and Tyrinna, but not in other species that also have coarse striations (Gymnodoris), and may constitute evidence for a close relationship. Tyrinna evelinae possessed fine acrosomal striations, which was shared with other Chromodorididae, Actinocyclidae and the cryptobranchs Rostanga and Aphelodoris. We also examined the sperm ultrastructure of ‘Chromodorisambiguus, an animal which has shown molecular affinities to species of Cadlina, and not Chromodoris. The sperm of ‘C.’ ambiguus did not exhibit the typical Cadlina characteristics, but also showed important differences to other investigated Chromodoris species.  相似文献   

8.

Plesiochorus Looss, 1901 is a genus of Gorgoderidae infecting the urinary bladders of marine turtles globally. Currently, just two morphologically similar species are recognised, Plesiochorus cymbiformis (Rudolphi, 1819) Looss, 1901 and Plesiochorus elongatus Pigulevsky, 1953, which have been distinguished by molecular data and subtle morphological differences. Here we describe a new species, Plesiochorus irwinorum n. sp., infecting hawksbill turtles (Eretmochelys imbricata (L.)), which is primarily distinguished from the other two species of Plesiochorus on the basis of ITS2, cox1 and 28S sequence data. Morphometric data for specimens examined during this study overlap between P. cymbiformis and P. irwinorum n. sp. for every measured feature, rendering them functionally cryptic. However, principal components analysis clearly distinguishes the two species. Additionally, we report new specimens of P. cymbiformis, and provide new sequence data for specimens from Australian loggerhead (Caretta caretta (L.)) and hawksbill turtles. There is little understanding of the host-specificity or geographical distribution of the three species of Plesiochorus, and it remains possible that some of the previously reported sequences have been attributed to the wrong species.

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9.
Five monorchiid species are reported from Diagramma labiosum Macleay (Perciformes: Haemulidae) collected from Heron Island on the southern Great Barrier Reef (GBR): two described species, Helicometroides longicollis Yamaguti, 1934 and Diplomonorchis kureh Machida, 2005 and three new species, including one new genus, Asymmetrostoma heronensis n. g., n. sp., Lasiotocus arrhichostoma n. sp. and Proctotrema addisoni n. sp. Helicometroides longicollis and D. kureh were previously reported from the closely related species Diagramma pictum (Thunberg) from Japan. Two further monorchiid species known from D. pictum, Genolopa plectorhynchi (Yamaguti, 1934) and Paraproctotrema fusiforme Yamaguti, 1934, appear to be absent from the southern Great Barrier Reef. Previous reports of two other monorchiids from D. labiosum from the GBR, Paramonorcheides pseudocaranxi Dove & Cribb, 1998 and Helicometroides vitellosus (Durio & Manter, 1968), are shown to have been made in error. The high richness of monorchiids and other trematode families in D. labiosum is consistent with that seen in other haemulids elsewhere.  相似文献   

10.
Representatives of the genus Camallanus Railliet & Henry, 1915 occur mainly in teleost fishes, although a significant number of species have also been recorded from anuran amphibians. The taxonomy, host range, geographical distribution and phylogenetic relationships of Camallanus spp. from African clawed toads (Xenopus spp.) are reviewed. Besides C. kaapstaadi Southwell & Kirshner, 1937, which shows a widespread distribution in sub-Saharan Africa and occurs in X. laevis subspecies, X. wittei, X. fraseri-like toads, X. borealis and X. muelleri, three new species were found: C. siluranae n. sp. from X. tropicalis in west Africa, C. macrocephalus n. sp. from X. borealis in Kenya, and C. xenopodis n. sp. from X. laevis laevis in South Africa and X. borealis in Kenya. C. johni Yeh, 1960 described from Xenopus sp. in Tanzania is considered a species inquirenda. C. kaapstaadi and C. macrocephalus are very closely related and both occur in the oesophagus of their hosts, unlike other Camallanus spp. which are found in the intestine or more rarely the stomach. Some of the unusual morphological features of these species may be an adaptation to attachment in the oesophagus. The host of C. siluranae, X. tropicalis, belongs to a separate species group (as has been established by recent molecular and cytological studies) to those of C. kaapstaadi, C. macrocephalus and C. xenopodis. Morphological affinities suggest that Camallanus spp. from clawed toads are not monophyletic with those from other amphibians and that C. siluranae is distantly related to, and probably not monophyletic with the remaining species from clawed toads. The Camallanus fauna of Xenopus spp. may thus be derived from at least two independent colonisations, of different host clades, by parasite lineages occurring in teleost fishes.  相似文献   

11.
Nine new species of Laboulbeniales parasitic on Staphylinidae from Ecuador are described and illustrated. These are: Corethromyces palumboi, parasitic on Sepedophilus sp. (Tachyporinae); Diandromyces onorei, parasitic on Hypotelus sp. (Piestinae); Dimeromyces osellae, parasitic on Plesiomalota cotopaxiensis Pace (Aleocharinae); Dimorphomyces carolinae, parasitic on Parosus sp. (Oxytelinae); Kleidiomyces ambiguus, parasitic on Anotylus sp. (Oxytelinae); Mimeomyces gregarius, parasitic on Philonthus sp. (Staphylininae); Monoicomyces trogacti, parasitic on Trogactus sp. (Oxytelinae); Scaphidiomyces pusillus, parasitic on Baeocera sp. (Scaphidiinae); and Teratomyces heterothopsis, parasitic on Heterothops sp. (Staphylininae).  相似文献   

12.
The Upper Zambezi River drainage of Zambia contains six Serrunochromis species belonging to the largemouth, piscivorous subgenus Serranochromis and three smallmouth, invertebrate-feeding species of the subgenus Sargochromis. A survey of the Barotse floodplain and associateddrainages revealed that two species, S. (S.) longimanus (Boulenger) and S. (S.) thumbergi (Castelnau), were uncommon on the floodplain. S. thumbergi appeared to be more abundant in the Kafue, Chobe, and Kabompo rivers than the Upper Zambezi proper. Adults of the three largest species (i.e. S. (S) robustus (Günther), S. (S.) altus (Winemiller & Kelso-Winemiller), and S. (Sar.) giurdi (Pellegrin)) inhabit the main channel of the Zambezi River during low water, whereas most adults of the other four species (i.e., S. (S.) macrocephalus (Boulenger), S. (S.)ungusticeps (Boulenger), S. (Sar.) codringtoni (Boulenger), and S. (Sar.) carlottae (Boulenger)) were collected from lagoons, canals and backwaters. Comparisons of population size structure and gonad condition during the falling water (May-August) and low water (September- December) seasons indicated that the seven common Serranochromis initiate spawning near the end of the low water period. Examination of gonad condition during the pre-spawning period indicated that Serrunochromis attain maturity at the following sizes: S. robustus, males (275-300 mm s.l .), females (250-275 mm); S. macrocephalus, both sexes (150-200 mm); S. altus, males (275-325 mm), females (250-300 mm);S. angusticeps, males (250-275 mm), females (175-225 mm); S. giardi, males (275-300 mm), females (225-250 mm); S. codringtoni, males (150 mm), females (125-150 mm); S. carlottue, males (150-175 mm), females (100-125 mm). Age was estimated from scale annuli comprised of closely spaced circuli that corresponded to the period of rising water (December- March). S. robustus, S. altus, S. angusticeps, and S. giurdi matured at approximately 3 years, and S. macrocephalus, S. codringtoni, and S. curlottae matured at approximately 2 years in the Barotse floodplain. The average numbers of mature oocytes per female were as follows: S. robustus- 1165; S. macrocephalus-810; S. altus-920; S. angusticeps-627; S. codringtoni-580; S. carlottue-362. Fecundity exhibited a weak positive relationship with female size. Analysis of stomach contents showed that interspecific diet overlap was low among both immature and mature size classes of Serrunochromis. Adult size classes of S. robustus fed primarily on small Synodontis catfishes, S. mucrocephalus fed mostly on mormyrid and cichlid fishes, S. altus specialized on mormyrids, and S. angusticeps fed primarily on small cyprinid and characid fishes. The three members of the subgenus Sargochromis consumed mostly invertebrates. Molluscs were the most important item in the diet of S. giardi, and aquatic insects and fish scales were predominant in the diet of S. carlottae. Larger size classes of S. codringtoni consumed large amounts of seeds (Graminaceae). If habitat and diet are considered together, niche separation among Upper Zambezi Serrunochromis species appears to be nearly complete.  相似文献   

13.
The species level taxonomy of Porthecla is revised. Six previously described species are recognized: P. ravus (Druce 1907); P. barba (Druce 1907); P. dinus (Hewitson 1867); P. porthura (Druce 1907); P. minyia (Hewitson 1867); P. gemma (Druce 1907), and another six new species are proposed: P. forasteira Faynel & Moser n. sp.; P. annette Faynel & Robbins n. sp.; P. johanna Faynel & Robbins n. sp.; P. peruensis Faynel & Moser n. sp.; P. prietoi Faynel & Busby n. sp. and P. willmotti Busby, Faynel & Moser n. sp. For each Porthecla species we present diagnostic characters, images of male and female adults, drawings of male and female genitalia, distribution maps, and notes on habitat and other biological traits. An identification key for males is provided. To stabilize names; lectotypes are designated for Thecla minyia Hewitson 1867, and Thecla gemma Druce 1907. Wing pattern resemblances between Porthecla and other genera are discussed.  相似文献   

14.
The growth, reproduction and condition of adults of the three dominant fish species (roach, Rutilus rutilus, (L.); perch, Perca fluviatilis, L. and ruffe, Gymnocephalus cernuus, (L.)) in the eutrophic Lake Aydat were studied over one year cycle. Compared to published data, the growth of R. rutilus and G. cernuus was about average, while that of P. fluviatilis was below average. Comparing to literature, the fecundity of R. rutilus and G. cernuus was low but their oocytes were large. In contrast, P. fluviatilis had a high fecundity but small oocytes. At the end of summer, an abrupt decrease in the condition was recorded only for perch, probably due to stress as a result of environmental conditions. The sex-ratio was in favour of females for the three studied species but, in contrast to G. cernuus, the sex-ratio of R. rutilus and P. fluviatilis increased significantly also with age. It is concluded that Lake Aydat is a more favourable environment for R. rutilus and G. cernuus than for P. fluviatilis.  相似文献   

15.
Aim To determine the origins of the host–parasite association between among yellow perch (Perca flavescens[Mitchill]) and the parasites Crepidostomum cooperi Hopkins, Proteocephalus pearsei La Rue and Urocleidus adspectus Beverly Burton. Of secondary interest are the parasites Bunodera luciopercae (Muller) and Proteocephalus percae (Muller) predictably associated with the Eurasian perch. Location The areas considered are the Holarctic, since the upper‐Cretaceous, and contemporary North America. Methods Published and new information from host and parasite phylogenies, palaeontology, palaeogeography and plate tectonics and host biology is incorporated to assess the origins of yellow perch and several of its parasites. This information is used to determine the origins for these host–parasite associations. Results Cladistic analysis suggests a Laurasian origin for Percidae and Perca, and that Perca is sister to the other genera in the family. Parasite phylogenies support a North American origin for the three species associated with yellow perch and a Laurasian origin for B. luciopercae. Proteocephalus pearsei and P. percae are not sister taxa. The fossil record for Perca dates to the Miocene in Europe and the Pleistocene in North America. North America and Europe were connected across the North Atlantic since at least the upper Cretaceous with separation complete by the Miocene. Europe was separated from Asia by the Obik Sea from the late Cretaceous until the Oligocene. Western cordillera orogeny and its accompanying high rates of water flow and Pleistocene glaciation represent barriers to Perca dispersal. Main conclusions The origin of Perca in North America dates at least to the late Oligocene when North America and Europe were connected across the North Atlantic and Europe and Asia were separate landmasses, and does not result from Pleistocene dispersal across Beringia from Asia. The present disjunction of Perca species in North America and Europe is due to the vicariant separation of North America and Europe. Based on the available information, yellow perch and its parasites have a North America origin. The association between yellow perch and the parasites in all cases is a consequence of host switching from other sympatric host species in North America and is not explained by co‐speciation. Even the association between the host‐specific Urocleidus adspectus and yellow perch originated with a host switch and is not due to co‐speciation. The basis for this host switching is geographical and ecological sympatry, especially shared feeding habits, with other North American fish hosts.  相似文献   

16.
The swimming crab Charybdis longicollis, native to the western Indian Ocean, was first recorded in the Mediterranean in 1954. It is now established from Egypt to Greece, and dominates the sandy-mud bottoms at 25–80?m in the southeastern Mediterranean. The success of C. longicollis is attributed to its high fecundity, agonistic behaviour and omnivorous diet, as well as the rise in seawater temperature. Since the early 1990s its populations in Israel and Turkey have been heavily parasitized by the alien rhizocephalan Heterosaccus dollfusi, which impacts its host’s behaviour, growth and fecundity, and causes mortality. Yet, 60 years after its first record in the Mediterranean, the population of C. longicollis seems durable, and has recently spread to the lower shelf and upper slope off Israel, where it is common at 80?m and is found down to 250?m, greatly increasing its spatial spread. The maximal percentage of parasitization was 87.2%, 88.8%, 75.5% and 81.8% at depths of 40, 60, 80, 100?m, respectively, and 50% at 120 and 250?m. Here, we hypothesize on the possible contribution of the depletion of its putative fish predators, mainly rays, to the prevalence of C. longicollis on the lower shelf.  相似文献   

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Gonadal cycles are described for Alathyria jacksoni and Velesunio ambiguus from the River Murray at Overland Corner (near Lock 3) and for V. ambiguus at Point Sturt, Lake Alexandrina. The study included periods of low flow (1982), minor flooding (1983) and intermediate flow (1986). In males, gametogenesis continued year-round with fertilisation in late winter. Female A. jacksoni brooded embryos in spring and released glochidia during spring and summer, whereas in female V. ambiguus, glochidia were present most of the year, with peak releases in spring and summer. In both species, the proportions of actively reproducing individuals varied. In the Murray, populations were influenced by variations in discharge. At Point Sturt, gonadal cycles in V. ambiguus were irregular, influenced by variable lake levels. Although both species are essentially gonochoristic, there were hermaphrodites in river and lake populations, and a female bias in the population at Point Sturt. Infections by parasitic trematodes at Point Sturt were rare, but occurred in 10% of A. jacksoni and 35% of V. ambiguus at Overland Corner. The river populations were also affected by gill damage due to unionicolid mites. The disparities in infections between river and lake mussels are unexplained, but did affect their reproductive activity.  相似文献   

20.
Summary Only nine species of the genus Haemonchus are considered valid, namely, H. contortus (Rudolphi, 1803) Cobb, 1898 (type), H. bedfordi Le Roux, 1929, H. dinniki Sach, Gibbons & Lweno, 1973, H. krugeri Ortlepp, 1964, H. lawrencei Sandground, 1933, H. longistipes Railliet & Henry, 1909, H. mitchelli Le Roux, 1929, H. similis Travassos, 1914 and H. vegliai Le Roux, 1929. These are redescribed. H. bispinosus Molin, 1860, H. placei Place, 1893, H. cervinus Baylis & Daubney, 1922, H. okapiae van den Berghe, 1937 (in part), H. tartaricus Evranova, 1940, H. contortus contortus Das & Whitlock, 1960, H. contortus cayugensis Das & Whitlock, 1960, H. contortus bangalorensis Rao & Rahman, 1967, H. contortus hispanicus Martínez Gómez, 1968, H. contortus kentuckiensis Sukhapesna, 1974 and H. contortus var. uktalensis Das & Whitlock, 1960 are considered synonyms of H. contortus (Rudolphi, 1803) Cobb, 1898.The synonymy of H. lunatus Travassos, 1914, H. atectus Lebedev, 1929, H. pseudocontortus Lebedev, 1929 and H. fuhrmanni Kamensky, 1929 with H. contortus is confirmed. H. okapiae van den Berghe, 1937 (in part) is considered a synonym of H. mitchelli Le Roux, 1929 and H. bubalis Chauhan & Pande, 1968 is considered a synonym of H. similis Travassos, 1914. H. bovis Bonelli, 1941 and H. contortus var. kashmirensis Fotedar & Bambroo, 1965 are considered species inquirendae. An illustrated key to the species of the genus is provided.Part of a thesis approved by the University of London for the award of the Ph.D. degree.Part of a thesis approved by the University of London for the award of the Ph.D. degree.  相似文献   

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