Pictured above is a breen brittle star its scientific name is ophiuroidea. This organism is closely related to basket stars which are related to star fish. A brittle star has a disc shaped body with five to eight arms that are long and slender with little spines all over them. This brittle star is green and somtimes looks like it glows in the dark. The mouth is surrounded by five moveable jaw segments, making the mouth opening look like a star. Some brittle stars are carnivorous, while others feed on small particles of plankton.The food enters the mouth and goes directly into the stomach, and there is no intestine and no anus; absorption and excretion are carried out instead by the five pairs of bursae located at the base of each of the arms. Water circulates in the bursae and there is an exchange of respirtory gases and excretion of wastes . The coelmic of thebursae contain the gonads that release the sperm cells in the water for fertilization. The larva , which form from a fertilized egg , is called an opiopluteus and is free swimming in the plankton until it transforms into a young stage when it settles on the bottom of the ocean. Brittle stars spawn at the end of summer and most spieces release thier eggs into plankton and invest no partenal care after. They can also reproduce asexually; like if an arm was to break off of a star and it still has a small piece of the central disk attached the arm can regenerate into a whole new star. Brittle stars don't like the light so they live under rocks in shallow water and some even live on the abyssal plains .


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