报道山东沿海贝类鳃表及外套腔中共栖的 3种触毛亚目盾纤类纤毛虫 :厚鱼钩虫(Ancistrum crassum)、日本鱼钩虫 (Ancistrum jap onicum)及亚桶形后口虫 (Boveriasubcylindrica)。文中依据活体观察、蛋白银及银浸法染色对其活体形态学、纤毛图式及银线结构进行了综合描述 ,对采自 4种不同宿主的厚鱼钩虫种群进行了比较研究。该文系后口虫属纤毛虫在我国的首次报道。 The species of Ancistrum crassum, Ancistrum jap onicum and Boveriasubcylindrica were reported in the gill epidermis and the coat lumen of Shandong coast. ). In this paper, the morphology, cilia pattern and silveryline structure were described based on in vivo observation, silver protein staining and silver immersion staining. The populations of hookworm larvae collected from four different hosts were comparatively studied. The article is the first time after the vermin ciliate in China reported.