褶累枝虫16SrRNA基因分析

以缘毛目褶累枝虫为研究材料,探索和建立了适用于较难培养的单细胞原生动物的分子生物学研究方法．并测定了褶累枝虫１６ＳｒＲＮＡ基因３′端１１１５个核苷酸．通过比较分析,从分子水平探讨了累枝虫属与缘毛目其它属之间的亲缘关系,为进一步重构原生动物的系统图提供最基本的资料．     

Evolutionary relationship and species separation of four morphologically similar stichotrichous ciliates （Protozoa, Ciliophora）

Phylogenetic and taxonomic studies on ciliate protists using molecular approaches have been demonstrated to be very reliable to form strong conclusions and results. In the present work, species separation of some morphologically similar stichotrichous ciliates, two species of Pseudokeronopsis and two species of Apokeronopsis, was reexamined using amplified ribosomal DNA restriction analysis (PCRRFLP). Five of 10 restriction enzymes revealed species-specific polymorphic patterns, of which four similar stichotrichs could be significantly separated and identified. Among them, EcoR I offered almost no significantly different restriction fragment patterns, but the four species could be separated from one another and identified with Hae III. Distinctly different restriction digestion haplotypes and similarity indices separated the species, and were used to construct a phylogeny. Phylogenies based on ITS2 nucleotide sequences and ITS2 secondary structures supported the separation of Pseudokeronopsis and Apokeronopsis using RFLP analysis, although three Pseudokeronopsis carnea populations did not cluster together. In addition, phylogenetic analyses using multiple algorithms confirmed that these two genera formed two distinct groups within the urostylids.     

Trichodina modesta Lom, 1970 (Ciliophora: Peritrichia) infestations of an endemic Toothcarp Aphanius danfordii Boulenger, 1890 (Pisces: Cyprinodontidae) in Sinop,Turkey

Toothcarp (Aphanius danfordii) were collected from a small stream connected to the Black Sea on the coast of Sinop, Turkey and examined for trichodinids. A total of 156 toothcarp was investigated. Trichodina modesta Lom, 1970 Lom, J. 1970. Observations on trichodinid ciliates from freshwater fishes.. Archiv für Protistenkunde, 112: 153–177.  [Google Scholar] was the only trichodina species recovered. Overall infestation prevalence (%), mean intensity and abundance values were 97.4%, 182.7±22.4 parasites per infested fish, and 178.0±22.0 parasites per examined fish, respectively. Infestation prevalence, mean intensity and abundance values in relation to sampling months, fish size, and sex were also determined and discussed.     

Protozoan ciliate epibionts on the freshwater apple snail Pomacea figulina (Spix, 1827) (Gastropoda,Ampullariidae) in an urban stream of south‐east Brazil

The objective of this study was to record and analyze the prevalence of ciliated protozoa associated with prosobranchian snails of the species Pomacea figulina collected from an urban stream in south‐eastern Brazil. Four collections were carried out between December, 2005, and March, 2006, from which 23 snails and 10 ‘empty’ shells were obtained. The shells and opercula were scraped over Petri dishes and the ciliates were observed using bright field and phase contrast microscopy. Seven species of ciliates were recorded on the snails of P. figulina. Of the 23 snails analyzed, 82.60% (n = 19) were infested with at least one species of ciliate. No ciliates were found on the ‘empty’ shells and opercula. The results are discussed in terms of ecological aspects involved in this association.