Red Sea Squirt

Back of Serra Gelada, Isla Mitjana, between Altea and Benidorm, Alicante (Spain).
Adult Red Sea-Squirts are about 6-12 cm long (maximum 20 cm). The colour (caused by symbiotic micro-algae) is red or vividly orange but paler on the side turned away from light. At depths below 15 m it looks black if no artificial light is used. They are upright and the tubular body is bulbous. The test is rough and finely granulated but clean due to antifouling impregnation. There are two cylindrical siphons equipped with a crown of rigid bristles, used as sensitive elements. The upper one is the oral opening which can be closed to a four-lobed cross; the lateral one is the cloacal exit which can be closed lip-like with two lobes.
(http://www.waza.org/en/zoo/choose-a-species/invertebrates/other-aquatic-invertebrates/halocynthia-papillosa)