[Life cycle of the trematode, Crowcrocaecum skrjabini (Iwanitzky, 1928) (Allocreadiata, Opecoelidae)]

Crowcrocaecum skrjabini has an intermediate and additional hosts. The mollusk Lithoglyphus naticoides serves as an intermediate host; the invasion extensity is 43.88% in summer and 28.57% -- in autumn and winter. In the experiment Gammarus (Rivulogammarus) balcanicus has turned to be an additional host and Carassius auratus givelia -- a definitive hot. The descriptions are given of cercaria (which belongs to a cotylocercal type), metacercaria and marita, reared in the experiment.