Plerocercoid

As Plerozerkoid (full fin ) the second larval stage of the tapeworms of the family of Diphyllobothriidae (eg fish tapeworm or Spirometra erinacei - European ) refers. The Plerozerkoid is encapsulated in the back muscles and in the liver of fish that act as transport hosts. Also, frogs, birds, snakes, pigs and hedgehogs can be transport hosts.

The unembryonierten eggs pass through Diphyllobothriidae introduced Humanfäzes or the feces of infected animals in fresh or brackish water, where they grow to buoyant hook larva. If the hook larvae of copepods ( zooplankton ), recorded in them develops from the Onkosphäre the Prozerkoid larva. The small crustaceans are in turn eaten by predatory fish as a transport host, evolved in their muscles from the Prozerkoid the Plerozerkoid. The then known as Sparganum larvae type accumulates in predatory fish when they eat the fried fish. When eating raw fish meat by the definitive host ( fish-eating birds and mammals, including humans ), it is then to receive the Plerozerkoiden that in the intestinal tract of the definitive host develop into the adult worm.