Dirofilaria Immitis
The Dirofilaria Immitis is more commonly known as Heartworm, it is a roundworm that is parasitic that is transferred through mosquito bites to the host. This parasite is a type of filaria that mainly affects dogs, and rarely humans. This parasite also mainly goes after the pulmonary arterial system and the heart. The adult heartworms also tend to migrate to the right side of the heart and try to infect great veins.
The Dirofilaria Immitis also have no circulatory system, they rely on diffusion to nearby nutrients outside of the organism in order to survive. This is not surprising due to the fact that these organisms are parasites that require the nutrients of others for survival. It also has a cavity that help the nutrients it needs enter its body as it takes it away from its host. This organism also plans on spending the rest of its life in the hosts' body and uses it to help with nutrient supply until its host finally dies.