Trophosome

Trophosome is an organ that houses bacteria that completely nourish their host. Trophosomes are found in the coelomic cavity of the giant tube worm, Riftia pachyptila or in the symbiotic flatworms of the genus Paracatenula. Symbiotic bacteria in the trophosome oxidize sulfur found in the tube worm's environment and produce organic molecules that the hosts can use as an energy source. This process is known as chemosynthesis.