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Two interesting species of cleistothecial Ascomycetes withAspergillus anamorphs are described:Fennellia flavipes andNeosartorya stramenia. Both species were isolated from soil smaples collected in 1992 as a new record to Japan.  相似文献   

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Pythium aquatile and P. macrosporum were isolated from the soil of a cultivated field in Gunma Prefecture and a forest in Nagano Prefecture for the first time in Japan. Their morphological characteristics are described, and their pathogenicity and taxonomy are discussed.  相似文献   

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The fresh waters of the Mekong basin are inhabited by five species of the pufferfish genusTetraodon Linnaeus, 1758 (sensu lato): the widely distributedT. leiurus Bleeker, 1851; two previously described species endemic to the Mekong,T. baileyi Sontirat, 1989 andT. suvattii Sontirat & Soonthornsathit, 1985; one new species endemic to the Mekong basins.Tetraodon baileyi has now been collected numerous times but only in or near rapids;T. abei, T. barbatus andT. suvattii are often but not exclusively associated with rapids or at least swift flowing streams; whileT. leiurus is found in almost all habitats except rapids.Tetraodon abei andT. barbatus are closely related toT. leiurus, from which they differ most strikingly in coloration.Tetraodon survattii differs from all of the others in having a strongly upturned mouth and light and dark stripes or spots radiating outwards from the eye.Tetraodon baileyi, the most distinctive Mekong pufferfish, has head and body more or less extensively covered with dermal cirri and is entirely scaleless.  相似文献   

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As new records from Japan, Tulostoma adhaerens and T. fulvellum (Tulostomataceae, Agaricales) were described and illustrated based on the specimens collected in Shizuoka Prefecture and Shiga Prefecture, respectively. New Japanese names were proposed as Abata-Keshibouzu-take and Tanemi-Keshibouzu-take for T. adhaerens and T. fulvellum, respectively, based on their morphological features.  相似文献   

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Two entolomatoid species associated with rosaceous plants, Entoloma saepium and E. clypeatum f. hybridum, are reported as new records from Japan, and their morphological characters are described and illustrated.  相似文献   

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A new species and two new Chinese records in the genus Ulocladium from soil are reported. New species is Ulocladium leve, and the new records are U. alternariae and U. consortiale. Latin diagnosis of the new species is presented. Holotype specimen (dried culture) of the new species and dried cultures of two new records are deposited in the Herbarium of Shandong Agricultural University: Plant Pathology (HSAUP).  相似文献   

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Functional consequences of trophic specialization in pufferfishes   总被引:2,自引:0,他引:2  
1. Trophic breadth may be correlated with behavioural and functional versatility or flexibility (Liem 1984), such that species with limited diets would be predicted to be less versatile or flexible in their feeding capabilities than would trophic generalists. The relationship was examined between the trophic breadth of a species and the degree to which muscle activity is influenced by prey type in two species of pufferfishes: Chilomycterus schoepfi, a specialist on hard-shelled prey, and Sphoeroides nephalus, a generalist predator. It was predicted that the specialist would show a decreased ability to alter its motor pattern in response to prey type and an increased amount of motor-pattern variability when feeding on different prey.
2. Electromyographic recordings of five feeding muscles were made from five individuals per species feeding on four prey types that differed in their hardness and escape abilities. Muscle-activity duration, relative onset and integrated rectified area were analysed for prey capture and manipulation behaviours for each prey type.
3. Prey-type effects on mean motor-pattern variables for capture were limited to one of 14 variables in each species. Prey effects on buccal manipulation were not significant for any of the 14 variables for C. schoepfi, but S. nephalus exhibited prey effects for seven out of 14 variables. No differences in motor-pattern variation were found for the strike, but species differed significantly in overall motor-pattern variability during buccal manipulation; C. schoepfi, the dietary specialist, exhibited greater motor variability than S. nephalus, the dietary generalist.
4. The results therefore support a direct relationship between the trophic breadth of a species and its functional versatility for buccal manipulation. In contrast, prey capture was a relatively stereotyped behaviour for both species, as few prey-type effects were found.  相似文献   

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Tetrodotoxin (TTX) is a highly potent neurotoxin that selectively binds to the outer vestibule of voltage-gated sodium channels. Pufferfishes accumulate extremely high concentrations of TTX without any adverse effect. A nonaromatic amino acid (Asn) residue present in domain I of the pufferfish, Takifugu pardalis, Na v1.4 channel has been implicated in the TTX resistance of pufferfishes . However, the effect of this residue on TTX sensitivity has not been investigated, and it is not known if this residue is conserved in all pufferfishes. We have investigated the genetic basis of TTX resistance in pufferfishes by comparing the sodium channels from two pufferfishes (Takifugu rubripes [fugu] and Tetraodon nigroviridis) and the TTX-sensitive zebrafish. Although all three fishes contain duplicate copies of Na v1.4 channels (Na v1.4a and Na v1.4b), several substitutions were found in the TTX binding outer vestibule of the two pufferfish channels. Electrophysiological studies showed that the nonaromatic residue (Asn in fugu and Cys in Tetraodon) in domain I of Na v1.4a channels confers TTX resistance. The Glu-to-Asp mutation in domain II of Tetraodon channel Na v1.4b is similar to that in the saxitoxin- and TTX-resistant Na+ channels of softshell clams . Besides helping to deter predators, TTX resistance enables pufferfishes to selectively feed on TTX-bearing organisms.  相似文献   

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A specimen of the filefish,Pervagor nigrolineatus, was collected from dead coral patches at a depth of 3 m in Zamami-jima, Kerama Islands (26° 14′ N, 127° 19′ E). This species is recorded for the first time from Japan. It has been known to be distributed in the tropical western Pacific from the Philippines to New Guinea (Hutchins, 1986). The present specimen is more similar in scale characters to the Philippine specimens than to the New Guinean ones.  相似文献   

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Cytogenetic analysis in two sympatric species of pufferfish from Paraná Coast, Brazil, Sphoeroides spengleri (Tetraodontidae) and Chilomycterus spinosus (Diodontidae) revealed the presence of 2n = 46 and 2n = 50 chromosomes, respectively. In S. spengleri, the double FISH technique with 5S and 18S rDNA probes showed no syntenical organization, with both multigene families occupying a terminal position on the chromosomes. In S. spengleri the poor pattern of heterochromatin distribution is discussed about its relation with the compactness of their genome. On the other hand C. spinosus presented conspicuous blocks occupying the short arms of several chromosomes, possibly consequence of an accumulative process. Heterochromatic supernumerary chromosomes were detected in both species, however in S. spengleri they were presented as microchromosomes varying of 0–3 and being more frequent in females than in males, possibly as result of a preferential segregation. Conversely in C. spinosus an extra chromosome was restricted to the males, which to behave as univalent during meiosis. In view of these peculiarities we hypothesized a possible relationship between B chromosome and sex determination, although others aspects on accumulation, maintenance, and frequency of these extra elements were also considered, focusing on the parasitic model. In spite of the karyotypic diversity and others genetic peculiarities in Tetraodontiformes, this corresponds the third report of the occurrence of chromosomes B in the group.  相似文献   

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