Difference Between Tapeworm and Roundworm

Tapeworm vs Roundworm

Tapeworms and roundworms do not sound themselves as friends to humans and most mammals and birds due to the danger that they can cause. Mostly, they both are internal parasites and cause problems to their hosts. Despite their similarity in the mode of life, tapeworms and roundworms belong to completely different phyla in the Animal Kingdom. This article summarizes the characteristics of both tapeworms and roundworms and presents a summary of difference between tapeworm and roundworm.


Tapeworms are a class of the Phylum: Platyhelminthes, aka flatworms. Their tape-like body with a number of segments would be the reason for calling them as tapeworms. Tapeworms are mainly the parasites of Gastro Intestinal Tract (GIT) of the vertebrates, especially mammals and birds. They live attached to the GIT wall or sometimes found as free-living organisms in the gut. When the digested food passes through the gut, tapeworms take advantage of it by consuming the food through suction. They absorb the food through their scolex or suction cups; sometimes there are tentacles in the scolex.

Tapeworm body is dorsoventrally flattened and composed of a series of segments that are connected to adjacent ones. Each segment is called a proglottid, and every segment is capable of living on its own with the presence of sexual organs of both sexes. In fact, each proglottid can be separated from the body of the main worm and it will develop into a complete worm and reproduce, as well. The nerve supply in tapeworms is considered as a very primitive system with five nerves and one ganglion. Therefore, their interconnection is a little weak but that has led them to be very effective in dispersing themselves among host organisms through separated proglottids.


Nematodes, the members of the Phylum: Nematoda, are also known as Round worms. There are about one million nematode species according to some of the estimations, and already 28,000 have been described. The majority of the Nematodes (16,000 species) are parasitic, and that is the reason for the notoriety about the round worms. The largest member of the phylum is about five centimetres long, but the average length is about 2.5 millimetres. The smallest species cannot be observed unless there is the aid of a microscope.

Roundworms have complete digestive systems with the mouth at one end of the body while anus located at the other end. The mouth is equipped with three lips, but sometimes the number of lips could be six, as well. They are not segmented worms, but the anterior and posterior ends are tapered or narrowed. However, there are few ornaments viz. warts, bristles, rings, and other small structures. The body cavity of Nematodes is a pseudo coelom, which is lined with mesodermal and endodermal cell layers. The cephalisation or the formation of head to be distinctive from the other body parts is not prominent among Nematodes, but they do have a head with nerve centres. The parasitic species have especially developed some nerve bristles to sense the environment that they live.

What is the difference between Tapeworm and Roundworm?

• Roundworms are Nematodes, but tapeworms are Platyhelminthes.

• Roundworms are a taxonomic phylum, while tapeworms are a taxonomic class of the Phylum: Platyhelminthes.

• Roundworms have a round body with tapered ends, whereas tapeworms have dorsoventrally flattened bodies.

• Tapeworms are composed of separable segments called proglottids, but roundworms do not have body segments.

• Roundworms can be found in GIT as well as in blood, but tapeworms are mainly found in GIT.

• Tapeworms are acoelomates, whereas roundworms are psuedocoelomates.

• Tapeworms are generally larger than roundworms are.

• Roundworms have a complete digestive system but not the tapeworms.