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1.
Two species of Nasicola Yamaguti, 1968 are described from the nasal cavities of tunas ( Thunnus spp.) from off the coast of Brazil: N. brasiliensis n. sp. from T. obesus (Lowe) and the type-species, N. klawei (Stunkard, 1962), from T. albacares (Bonn.). The new species is differentiated from N. klawei on the basis of the large number of testes and from N. hogansi Wheeler & Beverley-Burton, 1986 by its greater body-size, proportionately smaller haptor and smaller number of marginal spines. The host-specificity of Nasicola spp. is commented upon.  相似文献   

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Nine species of didymozoid trematodes referable to the genusDidymocystis Ariola, 1902 are reported from scombrid fishes of the Visakhapatnam coast, Bay of Bengal, India. They are:Didymocystis wedli fromThunnus tonggol; D. dissimilis fromKatsuwonus pelamis; D. alalongae fromT. tonggol; D. superpalati fromT. tonggol; D. bifurcata fromT. tonggol; D. oesophagicola fromT. tonggol; D. pinnicola fromK. pelamis; D. exiguus fromAuxis thazard andEuthynnus affinis; and a new species,D. guttatus, fromScomberomorus guttatus. The generaLagenocystis Yamaguti, 1970,Oesophagocystis Yamaguti, 1970 andDidymosulcus Pozdnyakov, 1990 are synonymised withDidymocystis. The synonymies ofUnivitellodidymocystis Yamaguti, 1970 andDidymocystoides Yamaguti, 1970, but notCoeliodidymocystis Yamaguti, 1970, withDidymocystis, as proposed by Pozdnyakov (1990), are accepted.Didymocystis bifasciatus (Yamaguti, 1970) is considered a synonym ofD. alalongae Yamaguti, 1970 andD. philobranchia Yamaguti, 1970 ofD. bifurcata Yamaguti, 1970. Of the nine species reported, eight constitute new reports from the Bay of Bengal. A key to the species ofDidymocystis from scombrid fishes of the Visakhapatnam coast is presented.  相似文献   

4.
Two species of Didymozoidae, Didymosulcus palati (Yamaguti 1970) and Didymosulcus philobranchiarca (Yamaguti 1970) were reported for the first time in South America, Atlantic Ocean, parasitizing three different tuna species from the coast of Rio de Janeiro, Brazil: Thunnus atlanticus (Lesson), Thunnus albacares (Bonnaterre) and Thunnus obesus (Lowe). Pairs of D. philobranchiarca were found on gill arches of T. albacares and T. obesus, in longitudinal rows of yellow cysts located inside grooves in the hard denticle palate (new site) of the three hosts species studied, and as disperse groups of cysts in the operculum (new site) and gill arches of T. atlanticus (new host record). D. palati occurred as disperse groups of encysted worm pairs in the gill arches of T. albacares and T. obesus and in gill arches and operculum of T. atlanticus (new host record). The pathological alterations induced by D. philobranchiarca in the palate of T. atlanticus are described for the first time. Original measurements and figures are presented.  相似文献   

5.
Diplectanum yamagutii sp.n., a gill parasite of Kyphosus cinerascens (Forsskål, 1775) off Hawaii is described from amongst the type-material deposited by Professor S. Yamaguti in the National Parasite Collection of the United States National Museum of Natural History at Beltsville (Maryland, USA). Diplectanum yamagutii sp.n., D. diplobulbus Yamaguti, 1968, D. nenue Yamaguti, 1968, D. spiculare Yamaguti, 1968 and D. kyphosi (Yamaguti, 1968) comb.n. are sympatric parasites of Kyphosus cinerascens off Hawaii. These five species are distinguished by the shape and size of the armature of both the cirrus and the haptoral sclerotised pieces.  相似文献   

6.
A rapid upward spawning rush is a nearly universal phenomenon among reef fishes that spawn pelagic eggs. Although spawning rushes have long been considered to have evolved as a defense against egg predators and/or attacks on the spawning fishes by piscivores, these hypotheses have never been tested in the field. We analysed piscivore attacks during three motor patterns associated with group spawning of the labrid fishThalassoma cupido at Miyake-jima, Izu Islands, Japan. Egg predation on group spawnings was also quantified. Of 206 piscivore attacks on spawning fishes by seven predator species, 17.1 (83.1%) occurred during 461 spawning rushes (1/2.7 spawning rushes). No attacks were successful during spawning rushes, and only four kills were made in 206 attacks summed from all three motor patterns associated with spawning, amounting to a piscivore success rate of only 1.9 %. In contrast, gametes from 90 of 213 spawnings (42.3 %) were consumed by nine species of planktivorous fishes. Spawning fish seemed not to recognize egg predators and made no attempt to avoid them, often spawning in the midst of waiting aggregations of damselfishes. Our data indicate that the rapidly of the spawning rush ofT. cupido serves as an excellent defense against piscivores, but is ineffective against egg predators. Evidence is presented from observations of seven other species suggesting that spawning ascents provide little protection against water column egg predators in predator-rich environments.  相似文献   

7.
We describe Kudoa ovivora n. sp. from ovaries of bluehead wrasse, Thalassoma bifasciatum, and record its presence in 6 species (Labroidei) collected in the San Blas Islands. Panama. Kudoa ovivora spores are quadrate with rounded edges in apical view, oval-shaped with apical valve extensions in side view (mean spore dimensions: length 6.5 microns, width 7.7 microns, thickness 6.9 microns; mean polar capsule dimensions: length 2.1 microns, width 1.5 microns). This is the first Kudoa species from gonads of fishes. Prevalence of infection varied among labrids (Thalassoma bifasciatum, Halichoeres bivittatus, Halichoeres garnoti, Halichoeres poevi), with T. bifasciatum exhibiting the greatest prevalence. Density of infection, measured as percent infected eggs, also varied among species with highest densities occurring in H. garnoti. Kudoa ovivora may not require an intermediate host because fishes fed infected tissue developed more infections than unfed fish. Infected eggs are inviable and larger and heavier than uninfected eggs. Infected eggs contain more organic and inorganic material, indicating that K. ovivora increases resource allocation to eggs. Therefore, infected females may have reduced growth, fecundity, and/or spawning activity. Because males were uninfected and all identified hosts are protogynous sequential hermaphrodites, further studies of K. ovivora may provide new insights on the costs/benefits of sex change.  相似文献   

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The similarities between Opecoelus Ozaki, 1925, Coitocaecum Nicoll, 1915, Opegaster Ozaki, 1928 and Paropecoelus Pritchard, 1966 and the difficulty of separating Opecoelus and Opegaster are discussed. It is proposed that Opegaster be reduced to synonymy with Opecoelus and the diagnosis of the latter amended to accommodate both forms. Four new species of Opecoelus are described from marine teleosts in Australian waters. These are Opecoelus woolcockae n. sp. from Acanthopagrus butcheri and A. australis from off South Australia, New South Wales and southern Queensland, O. pomatomi n. sp. from Pomatomus saltatrix off New South Wales, O. crowcrofti n. sp. from Atherinomorus ogilbyi off southern Queensland and O. queenslandicus n. sp. from Apogon fasciatus off southern Queensland. The following new combinations are formed: Opecoelus gonorhynchi (Gavrilyuk, 1979) n. comb., O. elongatus (Yamaguti, 1959) n. comb., O. pentadactylus (Manter, 1940) n. comb., O. apogonichthydis (Yamaguti, 1938) n. comb., O. cameroni (Caballero & Caballero, 1969) n. comb., O. dendrochiri (Yamaguti, 1970) n. comb., O. hawaiiensis (Yamaguti, 1970) n. comb., O. jamunicus (Srivastava, 1968) n. comb., O. longivesiculus (Yamaguti, 1952) n. comb., O. mastacembalii (Harshey, 1937) n. comb., O. mehrii (Harshey, 1937) n. comb., O. synodi (Manter, 1947) n. comb., O. tamori (Yamaguti, 1938) n. comb., O. bothi (Yamaguti, 1970) n. comb., O. caulopsettae (Manter, 1954) n. comb., O. beliyai (Pande, 1937) n. comb., O. brevifistulus (Ozaki, 1928) n. comb., O. cryptocentri (Yamaguti, 1958) n. comb., O. dactylopteri (Yamaguti, 1970) n. comb., O. dermatogenyos (Yamaguti, 1970) n. comb., O. ditrematis (Yamaguti, 1942) n. comb., O. gobii (Yamaguti, 1952) n. comb., O. hippocampi (Shen, 1982) n. comb., O. iniistii (Yamaguti, 1970) n. comb., O. lobulus (Wang, 1977) n. comb., O. macrorchis (Yamaguti, 1938) n. comb., O. parapristipomatis (Yamaguti, 1934) n. comb., O. pritchardae (Overstreet, 1969) n. comb., O. syngnathi (Yamaguti, 1934) n. comb., O. lutiani (Bravo-Hollis & Manter, 1957) n. comb., O. ovatus (Ozaki, 1928) n. comb., O. plotosi (Yamaguti, 1940) n. comb. and O. rectus (Ozaki, 1928) n. comb.; all the new combinations were previously species of Opegaster.  相似文献   

10.
应用生态学中的生态位宽度及生态位重叠研究方法,对中国云南人间鼠疫流行区11种蚤的宿主特异性及宿主选择进行了研究。宿主特异性用Levins生态位宽度进行测定。宿主选择用夹角余弦生态位重叠进行测定。结果表明:长形病蚤普洱亚种及印鼠客蚤的生态位宽度最窄、宿主特异性最高,近端远棒蚤二刺亚种及斯氏新蚤滇川亚种的生态位最宽、宿主特异性最低。印鼠客蚤(云南人间鼠疫流行区的主要鼠疫媒介)的优势宿主是黄胸鼠。印鼠客蚤较高的宿主特异性意味着该蚤可能主要在其优势宿主的不同个体间保存或传播鼠疫病原体。短突栉眼蚤及端凹栉眼蚤在宿主选择上较接近,而其它蚤种在宿主选择上差异较大。  相似文献   

11.
Members of the subfamily Thoracocotylinae are gastrocotylid monogeneans of Spanish mackerels (scombrid fishes of the genus Scomberomorus) from warm to warm-temperate seas around the world. We revise the diagnosis of the subfamily and recognise two genera and three species as valid. The genus Paradawesia Bravo Hollis & Lamothe Argumedo, 1976 is synonymised with Thoracocotyle MacCallum, 1913, and Dawesia Unnithan, 1965 and Methoracocotyle Lebedev, 1984 are synonymised with Pseudothoracocotyla Yamaguti, 1963. Thoracocotyle crocea MacCallum, 1913 (syns T. paradoxica Meserve, 1938 and Paradawesia bychowskyi Bravo Hollis & Lamothe Argumedo, 1976) is recorded from two species of Scomberomorus in the eastern Pacific (California to Peru) and four in the western Atlantic (South Carolina to Brazil). Pseudothoracocotyla ovalis (Tripathi, 1956) Yamaguti, 1963 (new syns Dawesia indica Unnithan, 1965, D. incisa Lebedev, 1970, Methoracocotyle scomberomori (Young, 1968) Lebedev, 1984, M. gigantica (Rohde, 1976) Lebedev, 1984 and Thoracotyle indica (Unnithan, 1965) Murugesh, 1995) is recorded from the gills of seven species of Scomberomorus from the Indo-west Pacific (eastern South Africa north to the Persian Gulf, and east to Fiji). Pseudothoracocotyla whittingtoni n. sp. is described from an eighth Indo-west Pacific scomberomorid, S. munroi, in Australian waters.  相似文献   

12.
Allozyme markers were used to identify anisakid nematodes from marine Japanese waters, morphologically assigned to three species complexes: Anisakis simplex (s. l.), Contracaecum osculatum (s. l.) and Pseudoterranova decipiens (s. l.). Samples assigned to A. simplex (s. l.) were found to correspond genetically to A. simplex sensu stricto, those of C. osculatum (s. l.) to C. osculatum A. No morphological characters are yet available to distinguish sibling species of these two complexes. As to the P. decipiens complex, two distinct species were detected: the first corresponded to P. decipiens C, previously recovered in the northern Atlantic, the second to P. decipiens D from Japan. The two species are genetically well differentiated, with five of the 19 loci tested showing distinct fixed alleles. Their reproductive isolation was proved by the lack of hybrids or recombinants in sympatric samples recovered from the same definitive host, Erignathus barbatus. P. decipiens D was found to correspond morphologically to Porrocaecum azarasi, previously considered a synonym of P. decipiens. Accordingly, the name Pseudoterranova azarasi (Yamaguti & Arima, 1942) n. comb. is proposed for P. decipiens D. Similarly, P. decipiens C fits in general morphology, type-locality and host with Ascaris bulbosa, also previously considered a synonym of P. decipiens. The name Pseudoterranova bulbosa (Cobb, 1888) n. comb. is proposed for P. decipiens C.  相似文献   

13.
The labrid tribe Odacini comprises four genera and 12 species of fishes that inhabit shallow kelp forest and seagrass areas in temperate waters of Australia and New Zealand. Odacines are morphologically disparate, but share synapomorphies in fin structure and fusion of teeth into a beak-like oral jaw. A phylogenetic analysis of odacines was conducted to investigate their relationships to other labrid fishes, the relationships of species within the tribe, and the evolution of herbivory within the group. Fragments from two mitochondrial genes, 12S rDNA and 16S rDNA, and two nuclear genes, Tmo4C4 and RAG2, were sequenced for seven odacine species (representing all four genera), eight species representing the other major labrid lineages, and three outgroup species. Maximum likelihood and maximum parsimony analyses on the resulting 2338 bp of DNA sequence produced nearly identical topologies differing only in the placement of a clade containing the cheiline Cheilinus fasciatus and the scarine Cryptotomus roseus. The remaining clades received strong bootstrap support under maximum parsimony, and all clades in the maximum likelihood analysis received high bootstrap proportions and high posterior probabilities. The hypsigenyine labrid Choerodon anchorago formed the sister group to the odacines. Within the odacines, Odax cyanoallix+Odax pullus formed the sister to the remaining odacines, with Odax acroptilus, Odax cyanomelas, and Siphonognathus argyrophanes forming successively closer sister groups to the clade Haletta semifasciatus+Neoodax balteatus. Either herbivory evolved twice in the odacines, or herbivory evolved once with two reversions to carnivory. The latter hypothesis appears more likely in the light of odacine feeding biology.  相似文献   

14.
Trypanosomes were isolated from Atlantic cod Gadus morhua L. collected from several fjords in western Norway. Morphological studies showed that the 12 infections studied represented a single species, identified as Trypanosoma pleuronectidium Robertson, 1906 which is resurrected and redescribed. This species is characterised by its body length (57.9 ± 5.4 μm), nearly central nucleus (NI = 1.05 ± 0.12) and relatively short post-kinetoplastic (PK) region (3.2 ± 0.8 μm). T. pleuronectidium is transmitted by the leech Calliobdella nodulifera (Malm). T. murmanense Nikitin, 1927 (emend.) is delimited to a species transmitted by the leech Johanssonia arctica (Johansson). This species is separated from T. pleuronectidium by its attained body length, more anterior nucleus, presence of cytoplasmic refractive granules, adnuclear vacuoles and by a longer PK region. Partial SSU rDNA sequences of T. pleuronectidium and T. murmanense from Norway (1980 nt) diverged by 1.9%. The nominal North Atlantic and Mediterranean trypanosome species are reviewed, and T. flesi Lebailly, 1904, T. bothi Lebailly, 1905 and T. limandae Brumpt & Lebailly, 1904 are considered synonyms of T. platessae Lebailly, 1904. T. triglae senegalensis Ranque, 1973 is not considered conspecific with T. triglae Neumann, 1909, and consequently raised to species status as T. senegalense Ranque, 1973. Some other likely synonymies are discussed. In addition to T. pleuronectidium and T. murmanense, the following marine teleost trypanosomes are provisionally listed as valid species pending further study: T. callionymi Brumpt & Lebailly, 1904; T. cotti Brumpt & Lebailly, 1904; T. delagei Brumpt & Lebailly, 1904; T. dorhni Yakimov, 1911; T. gobii Brumpt & Lebailly, 1904; T. laternae Lebailly, 1904; T. myoxocephali Fantham, Porter & Richardson, 1942; T. platessae Lebailly, 1904; T. scorpaenae Neumann, 1909; T. soleae Laveran & Mesnil, 1901; T. triglae Neumann, 1909; and T. yakimovi Yakimov, 1911.  相似文献   

15.
In no group of organisms has the link between species richness, morphological disparity, disparity in mechanics and functional or ecological diversification been made explicit. As a step towards integrating these measures of diversity, we examine how the mechanics of the anterior-jaw four-bar linkages of 104 species of Great Barrier Reef (GBR) labrid fishes maps into a scale-independent morphospace. As predicted from theory, no relationship exists between overall size and the mechanics of velocity and force transmission in labrid anterior-jaw linkages. Nonetheless, mechanics associated with the anterior jaw appear to have constrained diversification of labrid anterior-jaw morphology. Furthermore, simulations depict a generally nonlinear relationship between the length of individual links and transmission of motion. In addition, no relationship was found between morphological disparity and mechanical disparity among the most species-rich labrid groups from the GBR. It is also established that regions of morphospace equivalent in morphological disparity differ over nearly an order of magnitude in mechanical disparity. These results illustrate that without an explicit interpretation of the consequences of per unit change in morphology, conclusions about diversification drawn only from morphological disparity may be misleading.  相似文献   

16.
Four species of Stephanostomum are described from various sites in Seriola dumerili from off Corsica, France. S. ditrematis (Yamaguti, 1939), from the stomach, pyloric caeca and duodenum, has 36 circum-oral spines. S. seriolae Yamaguti, 1970 is considered a synonym of S. ditrematis. S. filiforme Linton, 1940, from the mid-intestine, has 43-46 circum-oral spines. S. petimba Yamaguti, 1970, from the rectum, has a 42 circum-oral spines. S. euzeti n. sp. has 49-51 circum-oral spines, and differs from worms with a similar anterior extent of the vitellarium and circum-oral spine number in details of the vitelline distribution and the distances between the gonads. Attention is drawn to the presence in the rectum of S. dumerili of sympatric species differentiated mainly on circum-oral spine number.  相似文献   

17.
Two new species of Pseudohapladena Yamaguti, 1952 (Digenea: Waretrematidae) are described. Pseudohapladena megoorchis n. sp. was obtained from the intestine of Mugil engeli (Bleeker) (Mugilidae), and Pseudohapladena lizae n. sp. from the intestine of Liza carinatus (Cuvier and Valenciennes) (Mugilidae). Pseudohapladena megaorchis is the most closely related in general morphology to Pseudohapladena scatophagi Yamaguti, 1952, but differs from the latter in the position of the hermaphroditic sac, and in the nature and distribution of the vitellaria. Features of P. lizae distinguishing it from other species of the genus include the shorter uterus, which contains only 1 egg, and the lesser extent of the vitellaria.  相似文献   

18.
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   

19.
Synopsis The mating system of the labrid fishThalassoma bifasciatum has been extensively described in the literature, and the species has formed the basis for much work in ecology and behavior. However, most work in the past on this species has concentrated in small patch reef habitats. Here I describe a different mating pattern in bluehead wrasses occurring on a large, linear barrier reef in St. Croix, U.S. Virgin Islands. On this reef, very large group-mating aggregations (> 10000 fish) form daily at a single area on the forepart of the reef. Tagging studies showed that fishes are faithful to particular feeding schools arrayed along the forereef, and that they migrate to the spawning grounds along a specific path from distances more than 1.5 km away. No mating appears to occur in other upcurrent areas of the forereef. One-way migration times averaged 52 min from the farthest site studied, and feeding does not occur en route. Despite large differences in time spent in migration, no significant differences existed in fecundity or frequency of spawning among females living at different distances from the mating aggregation. The only apparent differences was a significantlyhigher growth rate in the fishes residing farthest from the aggregation. This higher growth rate corresponded to a higher overall feeding rate in the distant location, suggesting that food intake can more than compensate for the increased costs of migration.  相似文献   

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