Honeycomb Worm, Sabellaria alveolata
The honeycomb worm (Sabellaria alveolata) is a species of worm that is classified within the Annelida phylum. Its range includes the Mediterranean Sea and the waters of Morocco north to the Atlantic Ocean, extending to the British Isles in the northeast. This species is known as a reef-forming polychaete, because its builds reefs. These reefs are shaped like a honeycomb, the feature from which worm derives its common name. The reefs are formed when the worms create tube-like structures within close proximity of each other and can reach an average breadth between twelve and twenty inches. The worm reaches an average body length between 1.2 and 1.6 inches. Its thorax holds three pairs of flat chaetal sheaths, which form an operculum that seal the opening of its shelter. The coloring of this species varies depending upon the type of substrate found in its area.
Image Caption: Sabellaria alveolata, partie anterieure de l’animal sorti de son tube. Credit: Auguste Le Roux/Wikpedia (CC BY 3.0)