Crown-of-Thorns Starfish
Starfish are found all over the world and can live across a wide range of depths. They live attached to the sea-floor. Despite their appearance, they are opportunistic feeders and predators. The Crown-of-Thorns Starfish follow these rules and they also are voracious predators of tropical coral in the Indo-Pacific area which is a unique quality.
Respiration occurs mainly through the tube feet and papulae that dot the body surface. Their water vascular system is where the exchange between oxygen and carbon dioxide occurs. Oxygen from the water is distributed through the body mainly by the fluid in the main body cavity. With no distinct excretory organs, excretion of nitrogenous waste is performed through the tube feet and papulae. The body fluid contains phagocytic cells, coelomocytes, which are also found within the hemal and water vascular systems. These cells engulf waste material, and eventually migrate to the tips of the papulae, where they are ejected into the surrounding water. Some waste may also be excreted by the pyloric glands and voided with the feces.
Respiration occurs mainly through the tube feet and papulae that dot the body surface. Their water vascular system is where the exchange between oxygen and carbon dioxide occurs. Oxygen from the water is distributed through the body mainly by the fluid in the main body cavity. With no distinct excretory organs, excretion of nitrogenous waste is performed through the tube feet and papulae. The body fluid contains phagocytic cells, coelomocytes, which are also found within the hemal and water vascular systems. These cells engulf waste material, and eventually migrate to the tips of the papulae, where they are ejected into the surrounding water. Some waste may also be excreted by the pyloric glands and voided with the feces.