putkiviertejä

Putkiviertejä, often translated as pipe worms or tube worms, are a diverse group of marine invertebrates belonging to the phylum Annelida, specifically the class Polychaeta. They are characterized by their sedentary lifestyle, living within tubes that they secrete or incorporate materials from their environment into. These tubes can be made of hardened mucus, calcium carbonate, or a combination of organic and inorganic particles.

The most well-known examples of putkiviertejä are the giant tube worms found in deep-sea hydrothermal vent ecosystems, such as *Riftia pachyptila*. These remarkable creatures lack a mouth and digestive system, relying instead on symbiotic bacteria housed within a specialized organ called the trophosome. These bacteria chemosynthesize energy from chemicals released by the vents, providing nourishment to their host.

Other species of putkiviertejä inhabit a wide range of marine environments, from shallow coastal waters to the deep ocean. They play important roles in their ecosystems, serving as a food source for other animals and contributing to sediment stabilization. Their tube-building activities can also create microhabitats that support a variety of other organisms. The diversity within this group is significant, with many species yet to be fully described and understood.