Introduction to the Cestodes
The cestodes consist of two seperate subclasses, the Cestodarians, parasites of fish and other cold blooded vertebrates. These are non-segmented parasites, with only a single set of sexual organs. In contrast, the more well known members of the Subclass Eucestoda are parasites of both warm and cold blooded vertebrates, including mammals such as man. They resemble a colony of individual animals in that their bodies are divided into a series of segments (the proglotids described in detail later in these pages), each with their own complete set of internal organs. There may be many hundreds of these proglotids, resulting in the complete parasite having a long, ribbon like body. The appearence of this long body is the origin for the common name for these parasites, the tapeworms.
There a number of Cestode parasites that have man as their main definitive hosts, as listed within this page. The common names of these parasites are often derived from their intermediate hosts, ingestion of which results in their infection, e.g. the Fish, Beef and Pork Tapeworms. Alternatively they may be named after the definitive host that the adult parasites are normally found in. For example the Rat tapeworm H. diminuta and the Dog Tapeworm Dipylidium caninum.