The Pineapple Sea Cucumber is also known as the prickly redfish and it is usually found in tropical waters such as the Red Sea. It grows up to about 30 inches and it is known for being covered with protruding thorns/branches on top of its main organ, the body. This is where it gets its name, the pineapple sea cucumber. Sea cucumbers have a water-vascular system and a haemal system, which has to do with blood. The water vascular system supplies the water pressure for the tentacles and tube feet so that locomotion can occur. The central haemal ring sends off additional vessels along the radial canals above and below the intestinal areas that connect to muscular ampullae. They act as smaller hearts to pump blood around the haemal system. Phagocytic coelomoctyes, defensive cells similar to white blood cells, are made in heal vessels and travel in both circulatory systems, showing that it has the ability to defend itself against sickness/disease.