弯睾鲫吸虫[Carasso trem a flecterotestis(Zhukov,1971)comb.nov.]及其毛蚴发育观察

Carassotrema flecterotestis (Zhukov, 1971) comb. nov. and observation of its miracidia development in vitro

本文对取自台湾海峡棱鮻(Liza carinatus)消化道的弯睾软穴吸虫(Hapalotremaflecterotestis Zhukov,1971)进行重新描述,并对其毛蚴的体外发育进行观察.根据Yamaguti(1971)区分单孔科(Haploporidae)和叉盘科(Waretrematidae)的标准,同意李敏敏(1984)将其从单孔科移出并入叉盘科.在与叉盘科已知属比较后,我们发现该吸虫除睾丸形状外,其他主要特征与鲫吸虫属(Carassotrema Park,1938)的相似.因此,我们拟将其作为后者的同物异名,并将该吸虫重新命名为弯睾鲫吸虫[Caras-sotrema flecterotestis(Zhukov,1971)comb.nov.].实验结果表明:在室温7～24℃(均值为15.3℃)条件下,其虫卵从单个卵细胞到毛蚴孵出共需12d.

Carassotrema flecterotestis (Zhukov, 1971) comb. nov. was collected from the intestine of Liza carinatus from the westerm coast of Taiwan strait.Its morphology was re-described and its miracidia development in vitro was observed. According to Yamaguti’s (1971) definitions of Waretrematidae and Haploporidae, we agree with Li’s (1984) opinion that Hapalotrema flecterotestis was transformed from the family Haploporidae to Waretrematidae. After the comparison of Hapalotrema Zhukov, 1971, which was erected by Zhukov (1971) with Hapalotrema flecterotestis from the intestine of Liocassis brashnicowi and Mugil so-iuy from the basins of the Japan and Yellow Seas, with other known genera of Waretrematidae, we find that the general characters of Hapalotrema, such as the shape and distribution of the vitellaria, and the position of the caecal bifurcation and ovary, are similar to those of Carassotrema Park, 1938 except for the shape of testis. However, the testis of known species of Carassotrema appears to have different shapes. We do not at this stage, however, consider this one feature as sufficient season to erect a new genus, and tendentiously regard (Hapalo-)trema as the synonym of Carassotrema and Hapalotrema flecterotestis Zhukov, 1971 is renamed as Carassotrema flecterotestis (Zhukov, 1971) comb. nov..C. flecterotestis differs from the other known species of Carassotrema in having a U-shaped testis, and well-developed esophagus with annulations. In this paper, the miracidia developments were worked out as well. Eggs laid by adult worms in 0.9% physiological saline were collected, and then kept in a small culture-dish containing sea water. Approximate half of sea water was changed every day. The proceeding of the miracidia development depends upon the temperature and needs about 12 days under laboratory conditions at room temperature of about 7～24℃ (15.3℃).