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1.
The present paper reports 7 species of pontoniine shrimps collected from Hainan Island,South China Sea,by the Joint Chinese-German Marine Biology Expeditions,in which,Conchodytes nipponensis(De Haan,1844)and Coralliocaris brevirostris Borradaile,1898 are new records from Chinese waters.  相似文献   

2.
Two nematode species of the genusDorylaimopsis (Family Comesometidae) from the Bohai Sea are described.Dorylaimopsis rabalaisi n. sp. similar toD. punctata Ditlevsen, 1918 from which it can be separated by the small size, short and simple spicules without ventral apophyses or joint line.Dorylaimopsis turneri n. sp. differs from the closest speciesDorylaimopsis angelae (Inglis, 1967) by its higher values of de Man ratio ‘a’, much shorter spicules and higher ratio of gubernacular to spicules length. A key to species of the genus based on the key by Jensen (1979) is given. This project was supported by the National Science Foundation, No: 3860804  相似文献   

3.
4.
Sequence variation of partial cytochrome b genes between two Coilia species, C. ectenes and C. mystus, was investigated. Of the 402 nucleotides, twenty-seven (6.72%) are polymorphic and all are synonymous substitutions. At the third positions of genetic condon of cytochrome b gene, the two species show an extreme anti-G bias (<4%) and a pronounced bias towards A and C (>68%). There is no amino acid sequence divergence between the partial cytochrome b genes of the two species, indicating a close genetic relationship between them. The k-2p genetic distance of partial cytochrome b segment of the two species is 0.072, suggesting that the species were separated 3.6 Ma ago, in the middle Pliocene. Our result reveals that the cytochrome b gene is an appropriate marker for studies of population genetic structures and phylogeographic patterns of the two species.  相似文献   

5.
Brine shrimp (Artemia parthenogenetica) which had ingested three water-insoluble antibacterial drugs i.e. sulfadiazine(SD), oxytetracycline (OTC) and erythromycin estolate (ERY-Es) were fed toTilapia and Mysis IIIof Penaeus orientalis K. The drug contents in the predators were then determined. After administration of drugs toTilapia and Mysis III, through the bio-encapsulation of the brine shrimp, efficacious therapeutical concentration of OTC and ERY-Es (but not SD) in the predators could be reached and maintained for more than 8 hours.  相似文献   

6.
Two new species of the genusTinocladia Kylin (1940)T. eudesmoides Ding et Lu sp. nov. andTinocladia zhangii Ding et Lu sp. nov., are described.T. eudesmoides is mainly characterized by its longitudinally and transversely produced sub-cortical filaments from the medulla, its short uniseriate assimilating filaments, usually composed of 6–10 cells with slightly swollen and narrow ultimate cells, and its unilocular sporangia (60–115)×55–70μm, variable in size.T. zhangii is mainly characterized by its very solid frond, not rip apart by hands, its evident longer primary branches, its short and slender secondary branches, with very evident sub-cortical layer, and filaments divided repeatedly, and its large and small unilocular sporangia, with the latter borne on an evidently swollen pedicel. Project B80981816 supported by the NSFC. Contribution No. 4443 from the Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.  相似文献   

7.
Ultraviolet mutagenesis was applied to Nannochloropsis oculata and three mutants resistant to 3-(3, 4-dichlorophenyl)-1,1-dimethylurea (DCMU) were isolated. The cellular chlorophyll a and total lipid content of the wild are higher in the medium supplemented with DCMU than in the control without DCMU. Without DCMU, the growth rates and chlorophyll a contents of the mutants are similar to those of the wild. Significant changes of fatty acid content and composition have occurred in DCMU-resistant mutants growing in the medium supplemented with DCMU. The total lipid, palmitic acid (16:0), palmitoleic acid (16:1ω9) and oleic (18:1ω9) contents decrease significantly, while the vaccenic acid (18:1ω11) increases significantly and the EPA content of dried powder increases slightly in the mutants. The study may provide a basis to improve EPA content in Nannochloropsis oculata in the future.  相似文献   

8.
A fragment of a large sub-unit ribosomal DNA (LrDNA) of 12 strains ofProrocentrum species was amplified by polymerase chain reaction (PCR). The PCR products were digested by 3 restriction endonucleases (Cfo I, Hae III, and RSA I) and then resolved in agarose gels. Results show that different species had different RFLP patterns, except forP. arcuatum (ME 131), which had the same pattern toP. micans (ME160 and 04). The same fragment of 19 strains of the genus was also amplified and subjected to denaturing gradient gel electrophoresis (DGGE). 11 different patterns were resolved. Different cultures of a same species had the same pattern. The results of RFLP and DGGE analyses showed that eight newly isolated epibenthicProrocentrum species were different from each other, and also from other cultured ones examined in this study.P arcuatum (ME132) could not be differentiated fromP. micans (ME160 and 04), it was probably mis-identified, since they are quite different morphologically.P. redfieldii (ME138) could also not be distinguished formP. triestinium (ME132), it should be regarded as a synonym ofP. triestinium. Unexpectedly, a restriction site was found inP. micans, compared with previous sequence data. Project supported by National Basic Research Priorities Program (2001CB409701, 2001CB409710) and supported by NSFC (40376040, 40025614)  相似文献   

9.
The ultrastructure of hemocytes ofPenaeus vannamei was examined by transmission electron microscope. Three types of hemocytes were identified: hyaline cell, small-granule cell and large-granule cell. Hyaline cells are the smallest of the hemocytes, lack electron-dense granules, have average size of 11.11 μm (SE±0.50,n=10)×6.96μm (SE±0.55,n=10), comprise 25.8% (SE±2.87,n=4×10) of the hemocytes; small granule cells are the most abundant type of hemocytes, comprise 58.1% (SE±3.40,n=4×10) of the hemocytes, contain small electron—dense granules, have average size of 10.78 μm (SE±0.60,n=10)×8.63 μm (SE±0.44,n=10); and large-granule cells comprise 16.1% (SE±2.55,n=4×10) of the hemocytes, are filled with large electron dense granules, have average size of 12.51 μm (SE±0.63,n=10)×8.99μm (SE±0.71,n=10). This research was supported by the National Climbing Project B, PDB6-6-3. Contribution No. 3448 from the Institute of Oceanology, Chinese Academy of Sciences.  相似文献   

10.
Several papers have reported that part or whole leafy thallus seemingly consisting of zygotospores can give rise to both blades and conchocelis in the same culture ofPorphyra. Study on samples of wild and cultivatedPorphyra yezoensis andP. oligospermatangia were conducted to clarify the origination of the young blades in the culture. It is confirmed that single cells on the blade of both species, which normally intermixed with zygotospores, germinated into young blades. TEM and SEM observation has shown that the single cells ofPorphyra yezoensis had typical features of female gamete (carpogonia) but archeospore. Therefore, the female gametes are responsible in developing leafy thalli. This project was sponsored by the NSFC (No. C-0205-05-39770593)  相似文献   

11.
Cloning and sequencing of the genes coding for the α- and β- subunit of phycoerythrin (PE) of a red alga—Gracilaria lemaneiformis (GL) are reported. Alignment of 1084 nucleotides sequenced with three known red algal PE genes,Rhodella violacea (RV),Polysiphonia boldii (PB) andAglaothamnion neglectum (AN), showed high level of conservation, and similarities of 77,6% (between GL and RV), 77.9% (GL and AN) and 79.0% (GL and PB). The similarities of amino acids were 84.8% (between GL and RV), 85.7% (GL and PB), and 80.6% (AN and GL), higher than those among nucleotides. Project 39670405 supported by NSFC and Japanese Science Promotion Society (JSPS).  相似文献   

12.
Thirty-nine isozymes in four tissues (mantle muscle, buccal bulb muscle, eye and liver) of Sepia esculenta were screened for enzymatic analysis using starch gel electrophoretic technique. Eighteen enzymes (G3PDH, LDH, MDH, MEP, IDHP, PGDH, GRS, NP, AAT, CK, AK, EST, ALP, ACP, FBP, MPI, GPI and PGM) show strong activities and good convergence in zymogram. They are proved to be suitable genetic markers in Sepia esculenta. Among the tissues used, mantle muscle is the best for electrophoretic analysis of isozymes. Eye and liver are fairly good for some special enzymes, such as LDH, EST, MPI, etc. Twenty-six loci are detected. The proportion of polymorphic loci is 0.115 in the Qingdao sample and 0.153 in the Rizhao sample (P<0.99). The mean values of the observed and expected heterozygosity per locus of Qingdao sample are 0.016 and 0.017, while those of the Rizhao sample are 0.023 and 0.025 respectively.  相似文献   

13.
The 5.8S ribosomal DNA sequences (5.8S rDNA) and their flanking regions, internal transcribed spacer 1 and spacer 2 (ITS1 and ITS2) of three new isolates in genus Alexandrium (Alexandrium sp. qd1, Alexandrium sp. qd2, Alexandrium sp. gz) from China were amplified, sequenced, and subjected to phylogenetic analysis. Alexandrium sp. gz and Alexandrium sp. qd1 were grouped with high bootstrap values with four strains/species, i.e., A. catenella South Korea strain, A. catenella Japan strain, and two from China, Alexandrium sp. AC03 and Alexandrium sp. AN01 being proposed to be A. catenalla in a previous study. Then Alexandrium sp. gz and Alexandrium sp. qd1 were identified as Alexandrium catenella. As A. catenella was isolated from Qingdao and Guangzhou sea areas, it supposedly distributed at least in these two areas and was genetically different. Alexandrium sp. qd2 differed greatly from species in Alexandrium. It clustered with Symbiodinium californium, Symbiodinium sp. G15 and Gymnodinium sp. Zhao 01 with 100% bootstrap value; so Alexandrium sp. qd2 affiliates to genus Symbiodinium, and is probably a free-living Symbiodinium species.  相似文献   

14.
The early stages and capsulogenetic stages of sporogenesis ofMyxobolus kwangsiensis were studied in detail by electron microscopy.M. kwangsiensis is an intracellular myxosporean infecting the epithelial cells of kidney tubules of young daceLabeo rohita. TheM. kwangsiensis sporogensis presents the typical features of myxosporea. The initial stages are multinucleate primary cells, with one primary cell typically enclosing one secondary cell. The secondary cells are formed directly by cytokinesis inside the primary cells. The primary cell participates in the formation of the secondary cell nucleus. The nuclear division of primary cell is asynchronous by amitosis. The parasitic organisms may degenerate inside the epithelial cells at any stage. The modes of sporoblast formation, the typical features of myxosporea and the cause of its degradation are discussed. This research was supported by the NSFC. (No. 39070675)  相似文献   

15.
The relationships between the neon flying squid, Ommastrephes bartrami, and the relative ocean environmental factors are analyzed. The environmental factors collected are sea surface temperature (SST), chlorophyll concentration (Chl-a) and sea surface height (SSH) from NASA, as well as the yields of neon flying squid in the North Pacific Ocean. The results show that the favorable temperature for neon flying squid living is 10°C–22°C and the favorite temperature is between 15°C–17°C. The Chl-a concentration is 0.1–0.6 mg/m3. When Chl-a concentration changes to 0.12–0.14 mg/m3, the probability of forming fishing ground becomes very high. In most fishing grounds, the SSH is higher than the mean SSH. The generalized additive model (GAM) was applied to analyze the correlations between neon flying squid and ocean environmental factors. Every year, squids migrate northward from June to August and return southward during October–November, and the characteristics of the both migrations are very different. When squids migrate to the north, most relationships between the yields and SST are positive. The relationships are negative when squids move to southward. The relationships between the yields and Chl-a concentrations are negative from June to October, and insignificant in November. There is no obvious correlation between the catches of squid and longitude, but good with latitude. Supported by the National High Technology Research and Development Program of China (863 Program, No. 2003AA607030); National Key Technology Research and Development Program (No. 2006BAD09A05)  相似文献   

16.
The living morphology and infraciliature of two rare marine ciliates, Placus salinus Dietz, 1964 and Strombidium apolatum Wilbert and Song, 2005, collected from the coastal waters near Qingdao, China, were investigated by in vivo observation and protargol impregnation technique. The improved diagnosis for Placus salinus is as follows: medium-sized marine Placus, in vivo (50–60)μm×(30–40)μm; cell elliptical to barrel-shaped; 28–31 somatic kineties; single macronucleus usually ellipsoid and one micronucleus located in the indention of the macronucleus; one contractile vacuole posteriorly positioned. Strombidium apolatum is characterized by: marine strombidium (40–60)μm×(30–45)μmm in vivo, cordiform in shape with somewhat pointed posterior end and conspicuous apical protrusion; extrusomes prominent, about 15μm in length and evenly arranged along the circle kinety; about 16 collar and 5–6 buccal membranelles; one elongate macronucleus and one micronucleus; circle and ventral kineties consisting of about 53 and 45 dikinetids respectively.  相似文献   

17.
A new species ofLiagora, L. perennis sp. nov. from Hawai’i, is described. Unlike species of this genus in China, it is carpotetrasporangial, and at the place of expected carposporangia bears cruciately divided tetrasporangia, a detail which differentiates it from the usual species ofLiagora without tetraspores that have been reported in China. Notes are provided on otherLiagora species that have an impact on the taxonomy of species found in China. Dedicated to the memory of Zhang Junfu(C. F. Chang) whose studies on marine algae I respect highly, and whose good-humored friendship I treasure.  相似文献   

18.
British Antarctic Survey (BAS) data collected near the Antarctic Peninsula area were used in this 1988/1989 study on the length frequency of three Antarctic fish species (Pleuragramma antarcticum, Electrona antarctica and Protomyctophum bolini) showing that the standard length (SL) ofP. Antarcticum ranged from 26.0 mm to 161.0 mm, that the 26.0 mm to 54.0 mm SL juveniles could be considered to be the age group 1 fish, and that the SL ofE. antarctica ranged from 39.4 mm to 89.7 mm for the males and 48.0 mm to 118.0 mm for the females, which may contain at least 6 age groups. This is more than previously thought.P. Bolini had 29.2 mm to 60.2 mm SL and complicated age composition.  相似文献   

19.
Hypoglossum fujianensis sp. nov. is an epiphytic alga in the intertidal zone. Plants are light red, 0.9–2 cm high. Margin of branches gives rise to uniseriate hair-like rhizoids, formed outward from the fusion of the second-and third-order cells. Blades are single layered (except the midrib) and uncorticated. Tetrasporangial sori are formed on the middle part of blades. The globular tetrasporangia are developed from lateral pericentral cells. Project 39391800 supported by the NSFC.  相似文献   

20.
Competition among HAB (Harmful Algal Bloom) species Dinoflagellate Alexandrium tamarense, Raphidophyte Heterosigma carterae, and Diatom Skeletonema costatum was studied in the laboratory. Experiments with these three major HAB species under combinations of different salinities (10, 18, 25, 30, 35) and temperatures (19℃, 25℃) were carried out. The results showed that S. costatum successfully competed with the other two species at salinities of 18, 25,30, and 35 at temperatures of 19℃ and 25℃. However, H. carterae showed its advantage at low salinity of 10 and became the single dominant species at salinity 10 and 25℃. A. tamarense could not compete successfully with the other two species especially at low salinities. However, it could remain at low density in the presence of higher densities of other algae.  相似文献   

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