重庆地区淡水鲶形目鱼类4种寄生车轮虫的分类

Morphological and Taxonomic Study of Four Species of Trichodinids Parasitic on Gills of Siluriformes Fishes from Freshewater

对3种鲶形目鱼类:光泽黄颡鱼(Pelteobagrus nitidus)、鲶(Silurus asotus)、大口鲶(Silurus meridionalis)进行了外寄生车轮虫多样性的调查研究,旨在澄清鱼类寄生车轮虫分类学的混乱,并为水产养殖中该类疾病病原的调查提供基础资料。借助Nikon E-600显微镜,采用活体观察以及干银染色法,运用国际间"统一特定描述"及"齿体定位描述"方法,对车轮虫的形态学特征、附着盘结构以及统计特征进行了研究。研究获得了4种隶属车轮虫属的寄生车轮虫即适度车轮虫(Trichodina modestaLom,1970)、易变车轮虫(Trichodina mutabilis Kazubski & Migala,1968)、喙状车轮虫(Trichodina rostrata Kulemina,1968)和蛙车轮虫(Trichodina ranaeDa Cunha,1950)。蛙车轮虫为中国新纪录种,且首次从鱼体检获,大口鲶是蛙车轮虫的新寄主记录;光泽黄颡鱼、鲶和大口鲶分别为适度车轮虫、易变车轮虫和喙状车轮虫的新寄主记录。

Ectoparasitic trichodinids from some siluriformes fishes, Peheobagrus nitidus, Silurus asotus, Silurus meridionalis in Chongqing, China, has been investigated in present work. The research paper aims at adding new data of fish parasitology for healthy culture. The observations in vivo are performed. The preparetions are made by dry silver impregnation technique examined under the Nikon E-600 phasecontrast microscope. All photomicrographs are made with the help of Nikon DXM-1200 and illustration drawings are carried out by computer software CorelDRAW 11.0, All measurements are presented in μm and follow the uniform specific characteristic system proposed by Lom（1985）. A detailed description of the denticles is presented in accordance with the method proposed by Van As and Basson（1989）. Four known species of trichodinids, subjected to genus of Trichodina are identified. These are Trichodina modesta Lom, 1970, Trichodina mutabilis Kazubski and Migala, 1968, Trichodina rostrata, Kulemina, 1968, Trichodina ranae Da Cunha, 1950. T. ranae which is first recorded from urinary bladder of frogs in Portugal, is reinvestigated from Silurus meridionalis in China. Distinguished by large-size, cap-like in shape when viewed laterally, centre of disc clear and without any guanules. Trichodina ranae is firstly isolated from the gills of freshwater fish and Silurus meridionalis is a new host for it. T. modesta, T. mutabilis and T. rostrata are isolated from new hosts, Peheobagrus nitidus, Silurus asotus, Silurus meridionalis respectively.