Spaghetti-worms

The term “spaghetti-worms” is used to describe members of this family (Terebellidae) for good reason: their long buccal (feeding) tentacles resemble strands of spaghetti. These tentacles are grooved, and the edges of the grooves are lined with cilia (hairs). A thin layer of mucus secreted in the groove picks up fine surface particles and with the aid of the beating cilia, tiny packages of food-laden sediment are delivered to the mouth. So what’s on the menu? Food items include detritus (organic material), unicellular algae and various small invertebrates. Using the cilia, the highly elastic tentacles engage in ciliary creeping—dancing and extending over the sediment surface, often causing the tentacles themselves to appear to be worms!
The spaghetti-worms are abundant, often very large and conspicuous marine worms. Some are known to host their commensal polychaete brethren, such as various scaleworm species. Mature male and female spaghetti-worms cannot be distinguished until just before spawning, when the developing gametes take on different colours: females loaded with eggs can be pinkish to greenish; males tend to be cream-coloured. A variety of modes of reproduction are known to occur, from broadcast (free) spawning of gametes, to brooding embryos inside the tube or inside a gelatinous mass.