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A new species of notothenioid fish, Pogonophryne bellingshausenensis n. sp., is described from the Bellingshausen Sea, Antarctica. The new species belongs to the dorsally-spotted “mentella”
group of the genus and is characterized by having a short (about 13% SL) mental barbel with a short (about 16% of barbel length),
narrow (barely wider than the stalk), and relatively inconspicuous terminal expansion composed of short, irregular, fingerlike
processes. Compared to most other dorsally-spotted species of Pogonophryne (“barsukovi”, “marmorata”, and “mentella” groups), P. bellingshausenensis has a relatively wide (about 7% SL) interorbital region. An unspotted patch on the median dorsal surface of the head, posterior
to the posttemporal ridges and anterior to the first dorsal fin, has not been observed previously in any dorsally-spotted
species. The holotype was collected at 1,947 m, one of the deepest records for any species of Pogonophryne. A revised key to the ten species of the “mentella” group of Pogonophryne is also provided. 相似文献
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A recent sample (28 specimens from South Georgia and 1 from Shag Rocks) of the plunderfish Artedidraco mirus collected in June 2004 during the ICEFISH Cruise yielded sufficient data to refute two long-held assumptions about this species: (1) it is endemic to South Georgia; (2) its mental barbel is sexually dimorphic (tapered in females and club-shaped with papillae in males). A. mirus exhibits three types of mental barbel: A: tapered without a terminal expansion; B: with a narrow terminal expansion composed of simple papillae; C: with a wide terminal expansion composed of convoluted or elaborately branched papillae. There is no correlation between barbel type and body size or sex. We also found sexual dimorphism in the relative height of the second dorsal fin (30% higher on average in males) and in the colour of the anal fin (black in males over 60 mm SL). The largest males possess a prominent ruffled urogenital papilla, also black in colour. Barbel histology resembles that of other artedidraconids (Dolloidraco
longedorsalis, Pogonophryne scotti) studied in containing large nerve trunks and blood vessels lateral to a pseudocartilaginous core and dermal papillae with an extensive network of nerves and blood vessels. The high degree of intraspecific variation in artedidraconid barbel structure warrants caution in using this structure as a diagnostic taxonomic character. 相似文献
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Three opisthomonorchiinae species are described from fishes obtained at the Fish Market in Nouméa, New Caledonia. Opisthomonorchis dinema n. sp. from Carangoides dinema Bleeker differs from the other recognised species in the genus by the long recurved genital atrium, arcing anteriorly. Also described are Opisthomonorchis carangis Yamaguti, 1952 from Carangoides sp. and Pseudopisthomonorchis thapari (Varma & Singh, 1979) n. comb. for Opisthomonorchis thapari Varma & Singh, 1979 from Carangoides chrysophrys (Cuvier). The features distinguishing Opisthomonorchis Yamaguti, 1952 and Pseudopisthomonorchis Madhavi, 1974 are discussed. 相似文献
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A new coccidia species Eimeria stizostedioni from the pikeperch Stizostedion lucioperca (Perciformes) is described. Localities: Neva river. Prevalence: 20% (1/5). Intensity of infection weak. Oocysts 7.5-8.0 x 10.0-12.5 microns. The form varies from oval up to ovoid; a wall is sleek, colourless, single-layer two-planimetric, micropyle, the polar granules and residual body are absent. Sporocysts 3.5 x 6.5 microns, with Stieda body and residual body represented by few small granules. Sporogony is endogenous. 相似文献
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E. Pisano F. Mazzei N. Derome C. Ozouf-Costaz J.-C. Hureau G. Prisco 《Polar Biology》2001,24(11):846-852
In the framework of the I.C.E.FISH (International Collaborative Effort on Antarctic Fish Adaptive Evolution) project, during the 1998-1999 season at the Italian shore-based Terra Nova Bay Station, the broad fields of adaptation and evolution of the fish suborder Notothenioidei were tackled through the integration of many disciplines. As a representative contribution of I.C.E.FISH, a cytogenetic study of the bathydraconid fish Gymnodraco acuticeps is reported. The Bathydraconidae is a heterogeneous notothenioid taxon whose intra-family relationships are very uncertain. The conventional karyotype and the location of nuclear ribosomal genes, by means of fluorescence in situ hybridisation, contributed to species-specific characterisation and provided the basis for comparative analyses. The karyotype of G. acuticeps consists of 48 chromosomes (2 metacentric, 2 submetacentric and 44 acrocentric); major ribosomal cistrons correspond to a large region in a single chromosome pair. Mapping of the available karyotypic data on a molecular phylogenetic tree provided information on chromosomal diversification during the cladogenesis of the bathydraconids. 相似文献
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Kudoa spp. from the musculature and intestinal mucosa of species of the teleost family Apogonidae were examined for their taxonomic identity. Two novel species are characterised: Kudoa cheilodipteri n. sp. from the musculature of Cheilodipterus quinquelineatus Cuvier, Ostorhinchus cyanosoma (Bleeker) and O. aureus (Lacépède); and Kudoa cookii n. sp. from the submucosa of the intestines of O. cookii (Macleay) only. Both species are characterised using morphology, small subunit ribosomal DNA (SSU rDNA), large subunit ribosomal DNA (LSU rDNA), and biological characters. Three new host records, O. cyanosoma, O. aureus and Apogon doederleini, and associated geographical, morphological and genetic data are also provided for Kudoa whippsi Burger & Adlard, 2010. Morphological and molecular intra-specific variation of all isolates assigned to K. whippsi is also examined. Phylogenetic analyses further support the idea that tissue tropism is a distinguishing character between morphologically similar species; species reported here display close relatedness to morphologically similar species infecting the same tissue within their hosts. 相似文献
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A collection of whole mount preparations of digeneans was studied. The parasites were collected from several species of fishes caught in a fishing area of the South Adriatic Sea. A host-parasite list is given. Twenty species of fish were analysed and twenty-seven species of digeneans were found, twenty of which had previously been described in the same host, and six of which were observed in new hosts and/or localities. One digenean, hitherto undescribed, is illustrated in this paper and described as Lecithaster atherinae n.sp. The new species can be distinguished from L. bombayensis by the testes not being lobed; from L. extralobus by having four rather than five ovarian lobes; from L. indicus and L. maeoticus by the ovarian lobes not being finger-like; from L. leiostomi by having definitely smaller eggs. 相似文献
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The karyotype of Histiodraco velifer from the Antartic Ocean was analyzed using various banding methods and in situ hybridization with a telomeric probe. A male and a female had a diploid set of 46 chromosomes (6 submetacentric + 40 acrocentric, FN = 52); the nucleolar organizer was CMA3-positive and was located on the short arm of a medium-sized submetacentric pair. All chromosomes stained uniformly with DAPI, whereas C-banding revealed heterochromatic blocks that were mostly located centromerically and telomerically and were resistant to ALUI digestion. The substantial identity of the karyotype of H. velifer with that of the other artedidraconids investigated so far suggests that chromosome changes must have played a less than significant role in the speciation among the lineages of this fish family endemic to Antarctica. 相似文献
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J. T. Eastman 《Polar Biology》1999,21(3):194-196
On the basis of five specimens, the icefish Dacodraco hunteri (Notothenioidei, Channichthyidae) is documented for the first time in the Ross Sea, Antarctica. Meristic counts and morphometric measurements are provided for this small, streamlined, laterally compressed species. D. hunteri has a weakly ossified skeleton with considerable cartilage in the skull. It has a partially persistent notochord and reduced amounts of bone in the vertebral column since the centra are incompletely constricted. Its weight in seawater averages only 1.28% of its weight in air and, as one of the lightest notothenioids, D. hunteri is probably a permanent inhabitant of the water column. The diet consists of relatively large specimens of the pelagic nototheniid fish Pleuragramma antarcticum. Accepted: 27 September 1998 相似文献
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Two sympatric species of Deretrema, D. combesae n. sp. and D. combesorum n. sp. are described from the manybar goatfish Parupeneus multifasciatus from off New Caledonia, South Pacific. D. combesae n. sp. does not fit any of the described Deretrema subgenera. The combination of the characters, tegumental spines, caeca reaching past the testes, the vitellarium reaching into the hindbody, much of the uterus at the level of and anterior to the gonads, a long oesophagus, testes in the hindbody and the pre-testicular ovary are not found in any of the described subgenera. D. combesorum n. sp. fits into the subgenus Deretrema (Deretrema), but differs from the described species in the sucker-ratio, eggs size, elongate shape and contiguous testes. The sympatry of these dissimilar species of Deretrema casts doubt on the value of the subgenera in Deretrema. 相似文献
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JOHANN-WOLFGANG WÄGELE 《Zoologica scripta》1988,17(2):195-211
New localities of several arcturids are reported from the Atlantic sector of the Antarctic Ocean. Antarcturus hempeli sp.n. is described and drawings from type material of the following species are presented: Antarcturus furcatus (Studer, 1882), A. polaris (Hodgson, 1902), A. glacialis (Beddard, 1886). A granulosus Nordenstam, 1933, A. antarcticus Bouvier, 1910, A. lillei Tattersall, 1920, A. coppingeri (Miers, 1881), A. hodgsoni Richardson, 1913. Of the 37 species known from the studied area only 6 occur in the high Antarctic Weddell Sea. It is suspected that the semi-sessile way of life yielded the evolution of many local species and races. 相似文献
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Rodolfo Elías Claudia Silvia Bremec Paulo da Cunha Lana José María Orensanz 《Hydrobiologia》2003,490(1-3):75-85
The diet of the brackish water tilapia Sarotherodon melanotheron is studied in various riverine and lacustrine systems of the Bia River basin (Côte d'Ivoire). Comparison of the diet between sampling sites (upper course, lower course and man-made Lake Ayame) shows significant differences. In the man-made lake, prey described as preferential include Asterionella (Bacillariophyceae) and Bosmina(Cladocera). In the lower course, the preferential preys are represented by Lyngbya(Cyanophyceae) while in the upper course Lyngbya and chironomid larvae are preferential. These differences are related to the altered environmental conditions generated by the construction of the dam on the Bia river main stream. In the man-made lake, there is no shift in diet either with the seasons (dry and rainy seasons) or with size. 相似文献
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Systematic Parasitology - The blue mackerel Scomber australasicus is one of the major commercial fishes consumed in southern Japan. Three species of parasitic copepods were collected from S.... 相似文献