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21.
海洋纤毛虫一新种——对虾聚缩虫   总被引:2,自引:0,他引:2  
于1989年对采自江苏赣榆青浦养殖场对虾体表的纤毛虫研究中,发现一大型共栖种,经鉴定系一新种,定名为对虾聚缩虫Zoothamnium penaei nov. sp.。本种特征为:虫体呈罈状,具双层的口围缘,表膜无明显环纹而常为细菌及碎屑物所覆盖,群体中个员大小相差显著,柄为不规则对称式双叉形分枝。模式标本存放于青岛海洋大学水产学院动物室。  相似文献   
22.
Protozoan communities developed in laboratory microecosystems were used to evaluate the toxic effects of lead ion. The lead was added as lead acetate in different concentrations (50 g · l–1, 20 g · l–1, 10 g · l–1 and 1 g · l–1). The protozoans were taxonomically identified and classified into functional groups according to their common nutritional type. The population dynamics of protozoa has been studied. In the control the most frequent groups were bacterivore-detritivores and photosynthetics (more than 75% of abundance). Noticeable lead effects were observed after 24 hours of exposure to metal in all fractions. In general, the lead caused reductions in the number taxa, in total protozoan abundance and in protozoan biomass. The diversity values decreased in more than two nep respect to control in the different fractions. At the end of assay, the protozoan communities structure was simplified in the fractions with lead and some species of little flagellates were dominant. The information provided by this microecosystems of protozoan community was more complex than the one provided by single-species bioassays. Community protozoan bioassays may give more information about the toxic effects to compare with actual ecosystems.  相似文献   
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