The life-cycle of Bucephaloides gracilescens (Rudolphi, 1819) Hopkins, 1954 (Digenea: Gasterostomata)

Abstract

The cercaria and sporocyst of Bucephaloides gracilescens are described from Abra alba (Wood). Observations were made on the behaviour of the cercaria and the mechanism of release from the first intermediate host. The metacercaria was obtained experimentally for the first time using Ciliata mustela (L.), a species of Gadidae from rock pools, as second intermediate host. It has not previously been recorded from this fish. Unsuccessful attempts were made to infect species of fishes from three other families, namely, Bothidae, Pleuronectidae and Gobiidae, confirming the high degree of host specificity of the metacercaria to Gadidae. The metacercaria, its development and effect on the host are briefly discussed. It was linked with the adult on the basis of comparative morphology and ecology of the hosts.