Symbiosis: ~ a mutually beneficial relationship between different people or groups.
Termitomyces is a genus of basidiomycete fungi belonging to the family Lyophyllaceae. There are 30-40 species in the genus, all of which are completely dependent on termites to survive. They are the food source for a subfamily of termites, the Macrotermitinae, who enjoy an obligate symbiosis with the genus similar to that between Atta ants and Attamyces mushrooms. Despite this relationship, spore transfer is still accomplished mainly by shedding from mushrooms, which protrude from the termite mounds.
From Wikipedia