They go through a generation of larval forms there. From there, they may be transmitted to other fish, and then to humans when they consume them. Tapeworms are also closely adapted to their hosts and they are highly specialized for the parasitic life style. Like flukes, they have intermediate and final hosts, but in the case of tapeworms, the intermediate host is often a vertebrate. The adult form lives in the intestines of the hosts.
Tapeworms are even more reduced in structure than flukes.
For example, they have no digestive tract. Unlike flukes, the body of tapeworms consists of a series of repeated segments, called proglottids , which contain their reproductive structures. These structures may break off, thereby allowing the tapeworm offspring to disperse from the host in its feces. The intermediate hosts of Taenia pisiformis are rabbits, while Dipylidium caninum uses fleas as intermediate hosts. Examine the scolex , or head of the tapeworm, which has hooks to anchor the worm in the intestine of the host.