The assassin bug is a very curious arthropod because it was only discovered in 2001 by a man named Alain Dejean. This bug is closely related to an ant. They live in colonies of abut 1,200 workers and one queen which is about twice the size of the worker. They first inject an enzyme into their prey that liquifies the inside for food. Then, the assassin bug takes the hollow body of that organism and puts it on its back for protection. This is essentially a shield. Like all arthropods, the assassin bug has an open cardiovascular system that does not contain arteries or a vein system. The fluid that is pumped throughout the body consists of mostly hemolymph with only 10% blood cells. The heart is located in the abdomen and the aorta is located near the head and runs down to the thorax. The hemolymph is pumped up from the heart to the aorta and through openings called ostia which lead to the different parts of the bug.