三种危害性纤毛虫的形态学研究

MORPHOLOGICAL STUDIES ON THREE MARINE PATHOGENETIC CILIATES

三种分离自海水养殖水体中的纤毛虫原生动物，含一新亚种及两种国内新记录：相似瓜形膜袋虫（新亚种），有唇篮口虫和贪食拟阿脑虫；本文对其纤毛图式及重要的形态学特征做了综合的描述。有唇篮口虫为可导致水质恶化的赤潮生物，其余两种则有明显的嗜污习性，或附于养殖动物的浅表部位从而有可能构成对宿主的危害。

Three marine pathogenetic ciliates have been morphologically studied:Nassula labiata Kahl,1933; Paranophrys carnivora Czapik & Wilbert, 1986 andCyclidium citrullus simile n. subspec. The first two organisms are new record in Chinawhich are either a red tidal form(Nassula labiata) or likely belonging to facultive parasitic forms (Paranophrys carnivora). Diagnostic features of Cyclidium citrullus simile n. subspec:small (12-16×7- 11um) marine form with one macronucleus, contractive vacuole caudally located;10- 11 bipolar somatic kineties with evenly distributed cilia; posterior part of SK(n-1), likethat in C. glaucoma, having close-set packed basal bodies. Ecological feature:saprobic marine water, salinity 31‰, temperature about 23℃.Type specimens as protargol impregnated slides are deposited in the Laboratory ofProtozoology, College of Fisheries, Ocean University of Qingdao, Qingdao 266003, P.R China. The new subspecies differs from the nominative Cyclidium citrullus citrullus Cohn,1865(= Cyclidium citrullus Cohn, 1865) n the different biotopes and smaller size(12- 16vs. 20-30um). We agree with some previous conclusions that the similar,well-known species, C. glaucoma Muller, 1786, should be considered as a strictfreshwater form, which can be distinguished from Cyclidium citrullus simile byevidently different body shape,habitats and larger size (25-30vs. 12-16um).