[Evolutive cycle of Paratimonia gobii, Prevot and Bartoli 1967 (trematoda-monorchiidea)].

The cycle of Paratimonia gobii PREVOT & BARTOLLI, 1967 (Trematoda-Monorchiidae), a parasite of Pomatoschistus microps (Teleostei gobiidae), has been discovered and carried out experimentally. The mollusc, first intermediary host, is Abra ovata (Lamellibranchiata, Scrobiculariidae). The gymnocephalous cercaria leaves the mollusc, then sucked in by the respiratory stream, becomes encysted in the inhaling siphon of another Abra. The accumulation of metacercaria results in the autonomy of this siphon and it is this cut-off organ which is becoming part of the alimentary chain of the final host allows the continuation of the cycle.