Hydroides norvegica

Hydroides norvegica is a species of worm that is classified within the Annelida phylum. This species is known as a tube-forming worm, because its builds tube-shaped reefs in order to shelter itself. Its range includes the waters of the Persian Gulf, the Red Sea, the Mediterranean Sea, the Atlantic Ocean, and the Indian Ocean. It prefers to reside in coastal areas on shells, rock piles, and boats. A study conducted in Hawaii showed that this worm was one of four predominant species that made their home on manmade structures submerged at fifty and one hundred feet below the surface. After four months, the worms reached a suitable size, but Padina Japonica, a type of brown algae, took over the entire space about nine months later.

Hydroides norvegica can reach an average length of about 1.8 inches. Its belly is typically red in color while the crown is red with white stripes. The operculum, which is surrounded by twelve to nineteen pairs of tentacles, is typically red in color or holds two red stripes. The worms’ body is comprised of about one hundred segments each bearing chitinous bristles known as chaetae. This worm is sedentary, remaining in its tube for its entire life with its head sticking out. The tube is white in color and reaches about 1.9 inches in length.

A study conducted in Madras Harbour, India focused on the growth rate and life cycle of Hydroides norvegica and other sedentary creatures. The study found that the worms would choose a strong surface and attach themselves to it, releasing translucent tubes that eventually calcified into tubes. Within the settings of the study, the worms created so many tubes that the surfaces became crowded and some vertical tubes were broken off by waves. Worms that were artificially fertilized within a laboratory developed normally, but some individuals reached an abnormal size of 3.9 inches. About ninety days after creating a safe tube, sexual maturity was reached and individuals began to breed.

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